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industrial

3
3
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3 #

digital equipment corporation

OS/8 Industrial BASIC

F o r additional c o p i e s , order N o . DEC- S8-OSIBA-A-D

from Software D i s t r i b u t i o n Center, D i g i t a l Equipment
Corporation, Maynard, Mass.

digital equipment corporation maynard. massachusetts

Printed October, 1973
Reprinted July, 1974

The information in this document is subject to change without notice
and should not be construed as a commitment by Digital Equipment
Corporation. Digital Equipment Corporation assumes no responsibility
for any errors that may appear in this manual.
The software described in this document is furnished to the purchaser
under a license for use on a single computer system and can be copied
(with inclusion of DIGITAL'S copyright notice) only for use in such
system, except as may otherwise be provided in writing by DIGITAL.
Digital Equipment Corporation assumes no responsibility for the use
or reliability of its software on equipment that is not supplied by
DIGITAL.

The HOW TO OBTAIN SOFTWARE INFORMATION page, located at the back of
this document, explains the various services available to DIGITAL
software users.
The postage prepaid READER'S COMMENTS form on the last page of this
document requests the user's critical evaluation to assist us in
preparing future documentation.

The following are trademarks of Digital Equipment Corporation:
CDP

DIGITAL

COMPUTER LAB
COMSYST
COMTEX
DDT
DEC
DECCOMM
DECTAPE
DIBOL

DNC
EDGRIN
EDUSYSTEM
FLIP CHIP
FOCAL
GLC-8
IDAC
IDACS

INDAC
KA10

PS/8

LAB-8
LAB-8/e
LAB-K
OMNIBUS
OS/8
PDP
PHA

RAD-8
RSTS
RSX
RTM
RT-11
SABR
TYPESET 8
UNIBUS

QU ICKPOINT

CONTENTS

Page
CHAPTER 1

INTRODUCTION TO O S / 8 INDUSTRIAL B A S I C

1-1

1.1
1.2
1.2.1
1.2.2
1.2.3
1.2.4
1.2.5

HARDWARE REQUIREMENT

1-1
1-2
1-2
1-2
1-2
1-2
1-2

1.3

LOADING AND RUNNING OS/8 INDUSTRIAL
BAS I C
G a i n i n g A c c e s s t o BASIC
E n t e r i n g t h e New Program
E x e c u t i n g the P r o g r a m
C o r r e c t i n g t h e Program
I n t e r r u p t i n g E x e c u t i n g of t h e Program
Leaving t h e C o m p u t e r
E x a m p l e of O S / 8 I n d u s t r i a l B A S I C R u n

1.3.1
1.3.2
1.3.3
1.3.4
1.3.5
1.3.6
1.3.7
1.4
1.4.1
1.4.2

CHAPTER 2

2.1
2.2
2.3
2.3.1
2.3.2
2.3.3
2.3.4
CHAPTER 3

3.1
3.2
3.3
3.3.1
3.3.2
3.4
3.5
3.5.1
3.5.2

DOCUMENTATION CONVENTIONS
Underlining
Carriage Return
B l a n k Spaces
C o n t r o l and S h i f t C h a r a c t e r s
Terminals

O S / 8 INDUSTRIAL B A S I C OVERVIEW

G e n e r a l System D e s c r i p t i o n
O S / 8 I n d u s t r i a l B A S I C Statements and
Commands

1-2
1-3
1-3
1-4
1-4
1- 4
1-5
1-5
1-6
1-6
1-6

O S / 8 INDUSTRIAL B A S I C ARITHMETIC

2-1

NUMBERS

2-1
2- 2
2-2
2-3
2-3
2- 4
2-5

VARIABLES
ARITHMETIC OPERATIONS
P r i o r i t y of A r i t h m e t i c O p e r a t i o n s

Parentheses
Relational Operators
R u l e s for E x p o n e n t i a t i o n
OS/8

INDUSTRIAL B A S I C STATEMENTS

STATEMENT NUMBERS
REMARK

-- THE COMMENTING STATEMENT

STATEMENTS FOR TERMINATING A PROGRAM
END
STOP
LET

-- THE ASSIGNMENT STATEMENT

INPUT/OUTPUT STATEMENTS AND FUNCTIONS
T h e INPUT S t a t e m e n t
T h e PRINT S t a t e m e n t

iii

3-1
3-2
3-3
3- 4
3-4
3-4
3-4
3-5
3- 5
3-6

Page

3.5.2.1
3.5.2.2
3.5.2.3
3.5.2.4
3.5.3
3.5.4
3.6
3.7
3.8
3.8.1
3.8.2
CHAPTER 4

General
Format Control C h a r a c t e r s
P r i n t i n g Numbers
PRINT Used w i t h INPUT
The T A B ( X ) Function
The PNT(X) Function
THE READ AND DATA STATEMENTS
RESTORE
CONTROL STATEMENTS

3-6
3-7
3-8
3-9
3-10
3-10
3-11
3-12
3-13
3-13
3-14

GOT0

IF-THEN and IF-GOT0
LOOPS

4-1

4.1

FOR AND NEXT STATEMENTS

4-1

4.2

NESTING LOOPS

4-2

LISTS AND TABLES

5-1

SUBSCRIPTED VARIABLES
THE D I M STATEMENT

5-1
5-2

OS/8 INDUSTRIAL BASIC FUNCTIONS AND
S UBROUT INES

G- 1

CHAPTER 5
5.1
5.2
CHAPTER 6

6.1

6.2
6.2.1
6.2.1.1
6.2.2
6.2.3
6.2.4
6.2.5
6.3
6.3.1
6.3.2
6.3.3

6.3.4
6.3.5
6.4
6.4.1
604.2
6.5

GENERAL INFORMATION ON OS/8 INDUSTRIAL
BAS I C FUNCTIONS
ARITHMETIC FUNCTIONS
The Random Number Function
FWD(X)
The RANDOMIZE Statement
The S i g n Function
SGN(X)
INT(X)
The I n t e g e r Function
The Absolute Value Function
ABS(X)
The Square Root Function
SQR(X)
TRANSCENDENTAL FUNCTIONS
The S i n e Function
SIN(X)
The Cosine Function
COS(X)
ATN(X)
The A r c t a n Function
The Exponential Function
EXP(X)
The N a t u r a l Logarithm Function
LOG(X)
USER DEFINED FUNCTIONS
The FNA(X) Function and the__DEFStatement
The UDEF Function C a l l and t h e USE
Statement

-- --

----

-- --

THE PEBUGGING FUNCTION

-- TRC(X)

6-1
6-2
6-2
6-4
6-4
6-5
6-5
6-6
6-6
6-6
6-6
6-7
6-7
6-7
6-8
6-8

6-8
6-9

Page
6.6
6.6.1
6.6.2
CHAPTER 7
7.1
7.1.1
7.1.2
7.1.3
7.1.4
7.1.5
7.2
7.2.1
7.2.2
7.2.3
7.2.4
7.2.5
7.2.6
CHAPTER 8
8.1
8.2
8.2.1
8.2.2
8.2.3
8.2.4
8.3
8.3.1
8.3.2
8.3.3
8.3.4
8.3.5
8.3.6
8.3.7
8.3.8
8.4
8.4.1
8.4.2
8.4.3
8.5
8.6
CHAPTER 9
9.1

9.1.1
9.1.2

SUBROUT INES
GOSUB and RETURN
Nesting Subroutines

6-11
6-11
6-12

ALPHANUMERIC INFORMATION (STRINGS)

7-1

STRING CONVENTIONS
Constants and Variables
Dimensioning Strings
Inputing String Data
Strings in LET and IF-THEN Statements
String Concatenation
STRING HANDLING FUNCTIONS
The LEN Function
The ASC and CHR$ Functions
The VAL and STR$ Functions
The POS Function
The SEG$ Function
The DAT$ Function

7-1
7-1
7-1
7-2
7-3
7-4
7-4
7-4
7-5
7-6
7-6
7-7
7-7

REAL TIME OPERATIONS

8-1

GENERAL DESCRIPTION
REAL TIME BASIC STATEMENTS
TIMER
COUNTER
CONTACT
DISMISS
EXTENDED FUNCTIONS FOR INPUT OR OUTPUT
The Clock Function
CLK(X)
Analog Input Function
ANI (C,G)
Analog Output Function
AN0 (C,V)
Read Digital Input
RDI (P,N)
Send Digital Output
SDO (P,N,V)
Read Digital Output
RDO (P,N)
Counter Input
CN1 (P)
Counter Output
CNO (P,V)
UPIR IDENTIFICATION FUNCTIONS
Line
LNE (x)
State
STA(X)
Count
CNT(X)
EXAMPLE CONTROL PROGRAM
POWER FAIL
RESTART

8-1
8-1
8-1
8-2
8-3
8-3
8-3
8-4
8-5
8-5
8-5
8-5
8-6
8-6
8-6
8-6
8-6
8-7
8-7
8-7
8-8

EDITING AND CONTROL COMMANDS

9-1

CORRECTING PROGRAMS

9-1

----

------- --

----

Erasing Characters and Lines
The RESEQ Program

9-1
9-2

Page
9.2

THE L I S T AND LISTNH COMMANDS

9-5

9.3

THE SCRATCH COMMAND

9-5

9.4

THE NEW COMMAND

9-6

9.5

THE OLD COMMAND

9-6

9.6

THE NAME COMMAND

9-7

9.7

THE SAVE COMMAND

9-7

9.8

THE RUN AND RUNNH COMMANDS

9-8

9.9

THE BYE COMMAND

9-8

FILES,

10-1

CHAPTER 10

10.1
10.1.1
10.1.2
1 0 .1.2.1
1 0 -1.2.2
10.1.2.3
10.1.2.4

F I L E STATEMENTS AND CHAINING

GENERAL INFORMATION ON OS/8
BASIC F I L E S
R e s i d e n t Devices
F i l e Descriptions
Fixed L e n g t h F i l e s
V a r i a b l e L e n g t h Files

INDUSTRIAL

10-1
10-1
10-1

Numeric F i l e s

10-1
10-1
10-2

ASCII F i l e s

10-2

10.2
10.2.1
10.2.2
10.2.3
10.2.4
10.2.5
10.2.6

F I L E STATEMENTS
T h e F I L E # Statement
T h e PRINT# S t a t e m e n t
T h e INPUT# S t a t e m e n t
T h e RESTORE# S t a t e m e n t
T h e CLOSE# Statement
T h e I F END# S t a t e m e n t

10-2
10-2
10-3
10-4
10-5
10-5
10-6

10.3

THE CHAIN STATEMENT

10-6

CREATING ASSEMBLY LANGUAGE FUNCTIONS

11-1

11.1

INTRODUCTION

11-1

11.2

THE OS/8

INDUSTRIAL BASIC SYSTEM

11-1

11.3
11.3.1
11.3.2
11.3.3

THE OS/8 INDUSTRIAL BASIC RUNTIME SYSTEM
INBRTS C o r e L a y o u t
INBRTS O v e r l a y s
INBRTS S y m b o l T a b l e s

11-2
11-2
11-3
11-4

11.4
11.4.1
11.4.2
11.4.3
11.4.4

DATA FORMATS
Variables

11-4
11-4
11-5
11-6
11-7

11.5
11.5.1
11.5.2
11.5.3
11.5.4

INBRTS SYMBOL TABLE STRUCTURE
T h e Scalar T a b l e
T h e A r r a y Symbol T a b l e
The String Symbol T a b l e
The String A r r a y T a b l e

CHAPTER 11

Strings
Incore DATA L i s t
The String Accumulator

11-7
11-7
11-7

11-8
11-9

11.6
11.6.1
11.6.2
11.6.3

FLOATING-POINT PACKAGE
F l o a t i n g - p o i n t Accumulator
F l o a t i n g - p o i n t Routines
Floating-point Operations
INBRTS SUBROUTINES
S u b r o u t i n e ARGPRE
S u b r o u t i n e XPUTCH
S u b r o u t i n e PSWAP
S u b r o u t i n e UNSFIX
S u b r o u t i n e STFIND
S u b r o u t i n e BSW
S u b r o u t i n e MPY
S u b r o u t i n e DLFCZAD
S u b r o u t i n e ABSVAL
PASSING ARGUMENTS TO THE USER FUNCTION
I n t e r f a c i n g FIELD 1 Code w i t h FIELD fl
Subroutines
Using t h e USE S t a t e m e n t
INBRTS I / O
Terminal I / O
INBRTS F i l e Formats
INBRTS B u f f e r Space
INBRTS Device Driver Space
The INBRTS I / O Table
INTERFACING THE ASSEMBLY LANGUAGE TO INBRTS
GENERAL CONSIDERATIONS AND HINTS
Routines Unusable by Assembly Language
Functions
Using OS/8
Page fl usage
ASSEMBLY LANGUAGE FUNCTION EXAMPLE
L I N K I N G I N T O THE INTERRUPT SKIP CHAIN

11-25
11-27
11-27
11-27
11-29

OS/8 BASIC STATEMENT, COMMAND, AND FUNCTION
SUMMARY

A- 1

APPENDIX B

COMPILE-TIME DIAGNOSTICS

B-1

APPENDIX C

RUNTIME DIAGNOSTICS

c-1

APPENDIX D

ASCII CONVERSION TABLE

D- 1

APPENDIX E

OS/8 INDUSTRIAL BASIC SYSTEM BUILD
INSTRUCTIONS

E-1

APPENDIX F

INDUSTRIAL BASIC SYSTEM GENERATION

F- 1

APPENDIX G

OPTIMIZING SYSTEM PERFORMANCE

G- 1

APPENDIX H

SYMBOL TABLE

H- 1

11.7
11.7.1
11.7.2
11.7.3
11.7.4
11.7.5
11.7.6
11.7.7
11.7.8
11.7.9
11.8
11.8.1
11.8.2
11.9
11.9.1
11.9.2
11.9.3
11.9.4
11.9.5
11.10
11.11
11.11.1
11.11.2
11.11.3

11.12

11.13

APPENDIX A

v ii

11-10

11-10
11-11
11-14
11-14
11-14

11-15
11-15
11-16
11-16
11-17
11-17
11-17
11-18
11-18
11-19
11-20
11-21
11-21
11-21
11-22
11-22
11-22
11-23
11-25

CHAPTER 1
INTRODUCTION TO OS/8

INDUSTRIAL BASIC

NOTE
BASIC I S A REGISTERED TRADEMARK
OF THE TRUSTEES OF DARTMOUTH COLLEGE.

BASIC i s an i n t e r a c t i v e programming language f o r a v a r i e t y o f
It i s used i n s c i e n t i f i c and b u s i n e s s environments t o
applications.
s o l v e both simple and complex mathematical problems w i t h a minimum of
programming e f f o r t .
I t is used by e d u c a t o r s and s t u d e n t s as a
problem-solving t o o l and as an a i d t o l e a r n i n g through programmed
i n s t r u c t i o n and simulation.

I n many r e s p e c t s t h e BASIC language i s similar t o o t h e r programming
languages (such as FOCAL and FORTRAN), b u t BASIC i s aimed a t
f a c i l i t a t i n g communication between t h e u s e r and t h e computer.
The
BASIC u s e r t y p e s i n t h e computational procedure as a series of
numbered s t a t e m e n t s , making use of common English words and f a m i l i a r
mathematical n o t a t i o n s .
Because of t h e small number of commands
n e c e s s a r y and i t s e a s y a p p l i c a t i o n i n s o l v i n g problems, BASIC i s one
of t h e s i m p l e s t computer languages t o l e a r n . W i t h e x p e r i e n c e , t h e
u s e r can add t h e advanced techniques a v a i l a b l e i n t h e language t o
perform more i n t r i c a t e manipulations or e x p r e s s a problem more
e f f i c i e n t l y and c o n c i s e l y .
OS/8 I n d u s t r i a l BASIC has such f e a t u r e s
as
chaining,
string
manipulation, and f i l e - o r i e n t e d input/output.
OS/8 I n d u s t r i a l BASIC
h a s added f e a t u r e s for s u p p o r t of t i m e based, and e x t e r n a l e v e n t
d r i v e n segments, coded i n BASIC, t o s e r v i c e t h e u s e r ' s real t i m e data
c o l l e c t i o n and response v i a DEC's UNIVERSAL DIGITAL CONTROLLER (UDC).

1.1 HARDWARE REQUIREMENT

The s t a n d a r d requirements f o r an OS/8 system must b e m e t .
t h e only d e v i c e s supported w i l l be:
1.

TD8-E w i t h e i t h e r ROM o r 1 2 K
UDC w i t h n o t more than 16 words I / O
DK8-EC c r y s t a l clock jumpered f o r 50 hz

RK8-E and DECtape
UDC w i t h n o t more t h a n 16 words I / O
DK8-EC c r y s t a l clock jumpered for 50 hz

1-1

In addition

1.2

DOCUMENTATION CONVENTIONS

1.2 1 Underlining

Where c l a r i f i c a t i o n i s r e q u i r e d i n t h e programming examples used i n
t h i s manual, u n d e r l i n e d copy denotes u s e r i n p u t .
Copy n o t u n d e r l i n e d
i n d i c a t e s e n t r i e s typed by O S / 8 I n d u s t r i a l BASIC.

1.2 2

Carriage return

r e t u r n is always typeL a t t h e end o f a l i n e t o i n d i c a t e
t h e l i n e i s complete.
The c a r r i a g e r e t u r n n o t a t i o n used i n t h i s
manual is t h e symbol J
A carriage

that

1.2.3

Blank s p a c e s

Blank s p a c e s are denoted by
required.

1.2.4

the

symbol u

where

clarification

C o n t r o l and s h i f t c h a r a c t e r s

C o n t r o l c h a r a c t e r s such as CTRL/O are typed by h o l d i n g down t h e CTRL
key and p r e s s i n g t h e letter 0. S h i f t c h a r a c t e r s such as SHIFT/L are
typed by h o l d i n g down t h e SHIFT key and p r e s s i n g t h e l e t t e r L.

1.2 5

Terminals

The use of t h e
DECwriter,

1.3

word

"terminal"

throughout

this

manual

implies

an ASR-33 T e l e t y p e , or an e q u i v a l e n t i n t e r a c t i v e device.

LOADING AND RUNNING O S / 8 INDUSTRIAL BASIC

The f o l l o w i n g d i s c u s s i o n assumes t h a t t h e O S / 8 o p e r a t i n g system f o r
t h e u s e r ' s hardware c o n f i g u r a t i o n i s on l i n e . The O S / 8 o p e r a t i n g
The
system is d e s c r i b e d i n t h e O S / 8 SYSTEM REFERENCE MANUAL.
f o l l o w i n g paragraphs are a condensation of t h e e d i t i n g and c o n t r o l
commands d e s c r i b e d i n Chapter 9 o f t h i s manual.

1-2

1.3.1

Gaining Access t o BASIC

Once t h e Keyboard Monitor has responded w i t h a p e r i o d t o i n d i c a t e t h a t
it i s ready t o r e c e i v e a monitor command, t h e user types t h e f o l l o w i n g
command :

.R INBSIC

BASIC responds w i t h t h e following:
NEW OR OLD

The u s e r t y p e s i n :
NEW FILE.EX

i f t h e user is going t o create a new program, where FILE.EX is t h e
I f t h e u s e r w a n t s t o work w i t h
name and e x t e n s i o n of t h e new program.
a p r e v i o u s l y c r e a t e d program t h a t he saved on a s t o r a g e d e v i c e , he
t y p e s i n t h e following:
OLD DEV:FILE.EX

where DEV: is t h e name o f t h e OS/8 d e v i c e h i s o l d f i l e i s s t o r e d on.
For example:

OLD DTA6 :SAMPLE BA

This response t o NEW OR OLD
retrieves t h e f i l e named SAMPLE from
DECtape and r e p l a c e s t h e c u r r e n t c o n t e n t s of u s e r core w i t h t h e f i l e
SAMPLE. I f you s p e c i f y a d e v i c e t h a t does n o t e x i s t o r t h a t is n o t
a v a i l a b l e f o r your use, INDUSTRIAL BASIC r e t u r n s an error message.
For f u r t h e r information regarding OS/8 f i l e s and d e v i c e s , r e f e r
Chapter 9 o f t h i s manual and t o t h e OS/8 SYSTEM REFERENCE MANUAL.

1.3.2

E n t e r i n g t h e New Program

A f t e r t h e u s e r t y p e s i n h i s filename, OS/8
w i t h t h e followingr

Industrial

BASIC

responds

READY

The user can begin t o t y p e i n h i s new program or make changes t o h i s
o l d program. When t h e new program i s b e i n g typed, t h e u s e r must make
s u r e t h a t each l i n e b e g i n s w i t h a l i n e number c o n t a i n i n g no more t h a n
f i v e d i g i t s and c o n t a i n i n g no spaces o r n o n d i g i t c h a r a c t e r s .
The
RETURN key must be p r e s s e d a t t h e completion of each l i n e .
I f , i n the
p r o c e s s o f t y p i n g a s t a t e m e n t , t h e u s e r makes a t y p i n g error and
n o t i c e s it b e f o r e h e terminates t h e l i n e , he can correct it by
p r e s s i n g t h e RUBOUT key or SHIFT/O keys once f o r each c h a r a c t e r t o b e
e r a s e d , going backward u n t i l the c h a r a c t e r i n error i s reached.
Then
he may c o n t i n u e t y p i n g , beginning w i t h t h e c h a r a c t e r i n error. Using
t h e RUBOUT key o r SHIFT/O keys echoes a backarrow (4) f o r each
character deleted.
The f o l l o w i n g i s an example of t h i s c o r r e c t i n g
p r o c e s s ( n o t e t h a t a c i s typed f o r s p a c e s as w e l l as c h a r a c t e r s ) :
2@ L)EN F b - e F

FNA(XaY)=Xt2+3*Y

1-3

corrected v e r s i o n of t h e above
subsequent l i s t i n g of t h e program as:

The

example

would

appear

DEF FNA(XaY)=Xt2+3*Y

Program l i s t i n g s can be g e n e r a t e d u s i n g t h e LIST or LISTNH commands.

1.3.3

Executing t h e Program

A f t e r t y p i n g the complete program (do n o t forget t o end w i t h an END
s t a t e m e n t ) , t h e u s e r t y p e s RUN or RUNNH, followed by t h e RETURN key.
OS/8 I n d u s t r i a l BASIC t y p e s t h e name of t h e program,
t h e v e r s i o n of
OS/8
I n d u s t r i a l BASIC, t h e c u r r e n t date ( u n l e s s RU"H i s s p e c i f i e d ) ,
and then it a n a l y z e s t h e program, I f t h e program can b e run, OS/8
I n d u s t r i a l BASIC e x e c u t e s it and, v i a PRINT s t a t e m e n t s , t y p e s o u t any
r e s u l t s t h a t were requested.
The t y p e o u t of r e s u l t s does n o t
g u a r a n t e e t h a t t h e program is correct ( t h e r e s u l t s could be wrong),
b u t i t does i n d i c a t e t h a t no s y n t a c t i c a l errors e x i s t (e.g.,
missing
l i n e numbers, misspelled words, or i l l e g a l s y n t a x ) . I f errors of t h i s
t y p e do e x i s t , OS/8 I n d u s t r i a l BASIC t y p e s a message (or s e v e r a l
messages) to t h e u s e r .
A l i s t of these d i a g n o s t i c messages, w i t h
their meanings, i s given i n Appendices B and C.
NOTE

RUN and RUNNH are c o n t r o l commands, and l i k e a l l
other OS/8
I n d u s t r i a l BASIC e d i t and c o n t r o l
commands, t h e y do n o t r e q u i r e a l i n e number
preceding t h e command.

1.3.4

C o r r e c t i n g t h e Program

I f the u s e r r e c e i v e s an error message t y p e o u t informing h i m ,
for
example, t h a t l i n e 6 0 is i n error, t h e l i n e can be corrected by t y p i n g
I f t h e s t a t e m e n t on
i n a new l i n e 60 t o r e p l a c e t h e e r r o n e o u s one.
l i n e 1 1 0 i s t o be deleted from your program, it i s accomplished by
t y p i n g t h e following:

1103
I f he wishes t o i n s e r t a s t a t e m e n t between l i n e s 60 and 70, t h e u s e r
t y p e s a l i n e number between 60 and 70 (e.g., 6 5 1 , followed by t h e
statement.

1.3.5

I n t e r r u p t i n g Execution of t h e Program

If the r e s u l t s b e i n g typed o u t seem t o be i n c o r r e c t and he wants t o
of h i s program, t h e u s e r t y p e s CTRL/C which i s echoed
by + e . The OS/8 I n d u s t r i a l BASIC e d i t o r responds w i t h t h e READY

stop execution

1-4

message whereupon t h e u s e r can modify or add s t a t e m e n t s and r e r u n h i s
program.

1.3.6

Leaving the Computer

When t h e u s e r ' s program i s f i n i s h e d and he no l o n g e r r e q u i r e s t h e u s e
Of OS/8
I n d u s t r i a l BASIC, he t y p e s t h e BYE command (or CTRL/C t o
r e t u r n c o n t r o l t o t h e Keyboard Monitor.

1.3.7

Example of OS/8

I n d u s t r i a l BASIC Run

The f o l l o w i n g i s a simple example of t h e u s e of OS/8

I n d u s t r i a l BASIC.

I n s t r u c t monitor
to
bring
i n t o core and s t a r t i t s
execution

.R ILJBSIC

BASIC

NEW OR OLD--NEW SAMPLE-BA

BASIC a s k s whether new or
program i s t o b e run

READY

BASIC is now ready t o

old

receive

statements
10 FOR N = l TO 7
28 PRINT N s S Q R < N )
30 NEXT N

Type i n s t a t e m e n t s

44 PRINT "DONE"
56 END

RUN
SAMPLE

Run program
BA

1 .o

22-SEP-73

1e41421

1073205
2
2.23687
2.44949
2.64575

4
5
6
7

DONE
READY

1-5

Program heading and r e s u l t s of
program are p r i n t e d .

1.4

OS/8

I N D U S T R I A L BASIC OVERVIEW

The e x p e r i e n c e d BASIC p r o g r a m e r may elect t o s k i p Chapters 2 and 4
through 6 of t h i s manual s i n c e t h e y are r a t h e r fundamental. However,
he should f a m i l i a r i z e himself w i t h t h e remaining c h a p t e r s
and
appendices as they provide i n f o r m a t i o n s p e c i f i c a l l y related t o OS/8
I n d u s t r i a l BASIC.

General System D e s c r i p t i o n

1.4.1

The OS/8

I n d u s t r i a l BASIC system i s d i v i d e d i n t o f i v e discrete p a r t s :

Editor

Compiler

Loader

Runtime System

Runtime System Overlays

The OS/8 I n d u s t r i a l BASIC E d i t o r i s used t o create and e d i t t h e s o u r c e
program.
On r e c e i p t o f a RUN command, t h e E d i t o r stores t h e program
i n a temporary f i l e and c h a i n s t o t h e Compiler. The Compiler compiles
t h e program i n t o p s e u d o - i n s t r u c t i o n s which are then loaded i n t o core
w i t h t h e Runtime System by t h e Loader. The Runtime System i n t e r p r e t s
each p s e u d o - i n s t r u c t i o n ,
c a l l i n g each of t h e Overlays i n t o core as
needed.
On completion o f t h e program, t h e Runtime System c h a i n s back
t o the Editor.
An OS/8
I n d u s t r i a l BASIC program c o n s i s t s of a
m a i n l i n e segment and u s e r p r o c e s s i n t e r r u p t r o u t i n e s .
U s e r process
i n t e r r u p t r o u t i n e s are executed i n response t o e x t e r n a l e v e n t s . A
more complete d e s c r i p t i o n of t h e OS/8 I n d u s t r i a l BASIC System is
provided i n Chapter 11 o f t h i s manual.

1.4.2

OS/8

I n d u s t r i a l BASIC Statements and Commands

I n d u s t r i a l BASIC c o n s i s t s of program s t a t e m e n t s and system
c o n t r o l commands which are needed t o w r i t e programs. A number of t h e
elementary OS/8 I n d u s t r i a l BASIC s t a t e m e n t s and commands are:
OS/8

O S / 8 INDUSTRIAL BASIC STATEMENTS

LET

Assign a v a l u e t o a variable.

P r i n t o u t t h e i n d i c a t e d information.

READ

I n i t i a l i z e variables t o v a l u e s from t h e
list.

1-6

data

DATA

Provide i n i t i a l data f o r a program.

GOTO

Change order of program e x e c u t i o n .

I F GOTO
I F THEN

Conditionally
execution.

change

order

program

FOR TO
STEP

S e t up a program loop.

End a program loop.

GOSUB

Go t o a subroutine.

RETURN

Return from a s u b r o u t i n e .

INPUT

G e t i n i t i a l v a l u e s from t h e t e r m i n a l .

RFIM

I n s e r t a program comment.

RESTORE

Restore t h e data l i s t .

DEF

Define a f u n c t i o n .

STOP

S t o p program e x e c u t i o n .

END

End a program.

DIM

Define s u b s c r i p t e d v a r i a b l e s .

UDEF

Define user-coded

TIMER
CONTACT
COUNTER

Associate i n t e r r u p t s e r v i c e r o u t i n e With
e x t e r n a l event.

DISMISS

Return from i n t e r r u p t s e r v i c e r o u t i n e .

OS/8

function.

INDUSTRIAL BASIC EDIT AND CONTROL COMMANDS

LIST

L i s t a l l stored program statements.

RUN

Run t h e c u r r e n t l y stored program.

SCRATCH

Delete t h e c u r r e n t l y stored program.

SAVE

Save t h e c u r r e n t l y stored program.

OLD

R e t r i e v e t h e old program.

NEW

P r e p a r e f o r a new program.

NAME

Rename t h e c u r r e n t l y stored program.

BYE

Exit f r o m BASIC.

1-7

OS/8 I n d u s t r i a l BASIC may e x e c u t e BASIC s t a t e m e n t s i n either of t w o
modes, mainline or u s e r process i n t e r r u p t .
Mainline Mode i s s t a n d a r d
BASIC sequence.
User Process I n t e r r u p t Mode i s used t o e x e c u t e
r o u t i n e s , s i m i l a r t o BASIC s u b r o u t i n e s , t h a t service e x t e r n a l e v e n t s .

These s t a t e m e n t s and commands are

explained i n detail w i t h a c t u a l
computer o u t p u t i n this manual.
For t h e convenience of t h e u s e r , a
detailed O S / 8 I n d u s t r i a l BASIC Statement, Command and Function Swnmary
is i n c l u d e d i n Appendix A.

1-8

CHAPTER 2
OS/8

2.1

INDUSTRIAL BASIC ARITHMETIC

NUMBERS

An OS/8 I n d u s t r i a l BASIC number may be any number i n t h e r a n g e of
10-6 1 6 < N < 1 O 6 l 6 .
OS/8 I n d u s t r i a l BASIC t r e a t s a l l numbers as decimal
numbers
t h a t i s , it a c c e p t s any number c o n t a i n i n g a decimal, and
assumes a decimal p o i n t a f t e r an integer. The advantage of t r e a t i n g
a l l numbers as decimal numbers i s t h a t t h e programmer can use any
number o r symbol i n any mathematical e x p r e s s i o n w i t h o u t r e g a r d t o i t s
type

I n a d d i t i o n t o i n t e g e r and decimal f o r m a t s , a t h i r d format i s
r e c o g n i z e d and accepted by OS/8 I n d u s t r i a l BASIC and i s used t o
e x p r e s s numbers o u t s i d e t h e range .OOOOl<x<999999.
T h i s format is
c a l l e d e x p o n e n t i a l or E-type n o t a t i o n and i n t h i s format, a number i s
e x p r e s s e d as a decimal number times some power of 1 0 . The form is:
xxEn
where E r e p r e s e n t s " t i m e s 1 0 t o t h e power of", t h u s
read: "xx times 1 0 t o t h e power o f n." For example:

the

number

Data may be i n p u t i n any one or a l l t h r e e of t h e s e forms. R e s u l t s o f
computations are o u t p u t as decimals i f t h e y are w i t h i n t h e r a n g e
p r e v i o u s l y s t a t e d ; o t h e r w i s e , t h e y are o u t p u t i n E format.
OS/8
I n d u s t r i a l BASIC h a n d l e s s i x s i g n i f i c a n t d i g i t s i n normal o p e r a t i o n
and i n p u t / o u t p u t , as i l l u s t r a t e d below:

Value Typed In

Value Output By OS/8 I n d u s t r i a l BASIC

.Ol
,0099
999999
1000000
.0000009

0.0099999
0.0099
999999
.100000E+007
.899999E-O06

OS/8 I n d u s t r i a l BASIC a u t o m a t i c a l l y s u p p r e s s e s t h e p r i n t i n g of l e a d i n g
and t r a i l i n g zeros i n i n t e g e r numbers and a l l b u t one l e a d i n g zero i n
decimal numbers.
A s can be s e e n from t h e p r e c e d i n g examples,
OS/8
I n d u s t r i a l BASIC formats a l l e x p o n e n t i a l numbers i n t h e form:
s i g n .xxxxxxE (+or-)n
where x r e p r e s e n t s t h e number c a r r i e d t o s i x decimal p l a c e s , E s t a n d s
f o r "times 10 t o t h e power o f , " and n r e p r e s e n t s t h e e x p o n e n t i a l
value.
For example:
-.3470213+009
,7260003-003

i s e q u a l t o -347,021,000
is equal to 0 . 0 0 0 7 2 6

2-1

2.2

VARIABLES

I n d u s t r i a l BASIC i s an algebraic symbol
r e p r e s e n t i n g a number, and i s formed by a s i n g l e l e t t e r o r a l e t t e r
followed by a d i g i t .
For example:

A simple v a r i a b l e i n OS/8

Unacceptable Variables

Accept abl e V a r i abl e s
I

- av adr iiagbi lte cannot begin a

- cannot
two
or
more
letters
form a variable

The u s e r may a s s i g n v a l u e s t o v a r i a b l e s e i t h e r by i n d i c a t i n g
v a l u e s i n a LET s t a t e m e n t , o r by i n p u t t i n g t h e v a l u e s as d a t a .

the

10 LET 1-53721
20 LET B3.5456.9
30 LET X=2OE9
40 INPUT Q
These o p e r a t i o n s , as w e l l as s u b s c r i p t e d v a r i a b l e s , are d i s c u s s e d i n
d e t a i l i n Chapter 5. A d i s c u s s i o n o f s u b s c r i p t e d and u n s u b s c r i p t e d

s t r i n g variables i s provided i n Chapter 7.
The meaning of t h e
=
s i g n should b e c l a r i f i e d .
In algebraic
However, i n OS/8
notation,
t h e formula X=X+1 i s meaningless.
I n d u s t r i a l BASIC (and m o s t computer l a n g u a g e s ) , t h e e q u a l s i g n
d e s i g n a t e s replacement rather t h a n e q u a l i t y . Thus, t h i s formula i s
a c t u a l l y t r a n s l a t e d "add one t o t h e c u r r e n t value of X and store t h e
new r e s u l t back i n t h e same v a r i a b l e X". Whatever v a l u e s had p r e v i o u s l y
been a s s i g n e d t o X w i l l be combined w i t h t h e v a l u e 1.
An e x p r e s s i o n
such as A=B+C i n s t r u c t s t h e computer t o add t h e v a l u e s of B and C and
store t h e r e s u l t i n a t h i r d v a r i a b l e A. The v a r i a b l e A i s n o t b e i n g
e v a l u a t e d i n terms of any p r e v i o u s l y a s s i g n e d v a l u e , b u t o n l y i n terms
of B and C. Therefore, i f A has been assigned any v a l u e prior t o i t s
u s e i n t h i s s t a t e m e n t , the o l d v a l u e i s l o s t ; it is i n s t e a d r e p l a c e d
by t h e v a l u e of B+C.

2.3

ARITHMETIC OPERATIONS

I n d u s t r i a l BASIC performs a d d i t i o n , s u b t r a c t i o n , m u l t i p l i c a t i o n ,
as w e l l as more complicated o p e r a t i o n s
d i v i s i o n and e x p o n e n t i a t i o n ,
e x p l a i n e d i n d e t a i l l a t e r i n t h e manual. The f i v e operators used i n
w r i t i n g most formulas are:
OS/8

2-2

Symbol
Operator

Meaning

Example

Addition

A + B

Subtraction

A - B

Multiplication

A * B

Division

A / B

Exponentiation

t B o r (A**B)

(Raise A t o t h e B Power)

2.3.1

P r i o r i t y of A r i t h m e t i c Operations

I n any given mathematical formula, O S / 8 I n d u s t r i a l BASIC performs
a r i t h m e t i c o p e r a t i o n s i n t h e following o r d e r :

the

Parentheses receive t o p p r i o r i t y .
Any e x p r e s s i o n w i t h i n
is
evaluated
before
an
unparenthesized
parentheses
expression.

I n absence of p a r e n t h e s e s , t h e o r d e r of p r i o r i t y i s :

Exponentiation

M u l t i p l i c a t i o n and Division (of e q u a l p r i o r i t y )

Addition and S u b t r a c t i o n (of e q u a l p r i o r i t y )

I f e i t h e r 1 or 2 above does not c l e a r l y d e s i g n a t e t h e o r d e r
of p r i o r i t y , then t h e e v a l u a t i o n of e x p r e s s i o n s proceeds from
l e f t t o right.

The e x p r e s s i o n A/B*C i s e v a l u a t e d from l e f t t o r i g h t as follows:

2.3.2

A/B

= step 1

( r e s u l t of s t e p l ) * C

= answer

Parentheses

P a r e n t h e s e s may be used by t h e programmer t o change t h e o r d e r of
p r i o r i t y (as l i s t e d i n r u l e 2 above), because e x p r e s s i o n s w i t h i n
p a r e n t h e s e s are always e v a l u a t e d
first.
Thus,
by
enclosing
e x p r e s s i o n s a p p r o p r i a t e l y , t h e programmer can c o n t r o l t h e o r d e r of
evaluation.
Parentheses may be n e s t e d , o r enclosed by a second s e t
(or more) o f parentheses.
I n t h i s case, t h e e x p r e s s i o n w i t h i n t h e
innermost p a r e n t h e s e s i s e v a l u a t e d f i r s t , and then t h e n e x t innermost,
and so on, u n t i l a l l have been e v a l u a t e d ,
Consider t h e following example:

2- 3

A=7* ( ( B t 2 + 4 ) /X)
The o r d e r of p r i o r i t y is:
1.

Bt2

= step 1

( r e s u l t of s t e p 1 ) + 4

= step 2

( r e s u l t of s-tep 2 ) / X

= step 3

( r e s u l t o f s t e p 3)*7

= A

P a r e n t h e s e s also p r e v e n t
expression is evaluated.

any confusion
For example :

doubt

how

the

A*Bt2/7+B/C+Df2
((A*Bt2)/7) + ( (B/C) + D t 2 )
Both of these formulas w i l l be executed i n t h e same way. However, t h e
i n e x p e r i e n c e d p r o g r a m e r o r s t u d e n t may f i n d t h a t t h e second i s easier
t o understand.
Spaces may also be used t o i n c r e a s e r e a d a b i l i t y .
Since t h e
I n d u s t r i a l BASIC compiler i g n o r e s s p a c e s , t h e t w o s t a t e m e n t s :

OS/8

10 LET B = D t 2 + 1
10 LETB=Dt2+1

are i d e n t i c a l , b u t s p a c e s i n
reading.

2.3.3

the

first

statement

provide

ease

R e l a t i o n a l Operators

a t some p o i n t t o
d i s c o v e r t h e i r r e l a t i o n t o one another.
To accomplish t h i s , OS/8
I n d u s t r i a l BASIC makes use o f the f o l l o w i n g r e l a t i o n a l o p e r a t o r s :

A program may r e q u i r e t h a t two values be compared

= equal t o
< less t h a n
> greater t h a n
=< o r <= less t h a n or e q u a l t o
=> o r >= g r e a t e r t h a n o r e q u a l t o
>< o r <> n o t e q u a l t o

Depending upon t h e r e s u l t o f t h e comparison, control of program
e x e c u t i o n may be d i r e c t e d t o a n o t h e r p a r t of t h e program.
Relational
operators are used i n c o n j u n c t i o n w i t h t h e IF-THEN s t a t e m e n t which i s
d i s c u s s e d i n Chapter 3.

2-4

2.3.4

Rules f o r Exponentiation

The following r u l e s apply i n e v a l u a t i n g t h e e x p r e s s i o n AtB.

Rule
-

Example

If B=O, then A + B = l

3t O = l

If A=O and B>O, then A+B=O

0+2=0

I f Ax0 and B<D, then AtB=O
and a DV error message i s
p r i n t e d (See Appendix C ) .

0 +-2=0

I f B i s an i n t e g e r > 0 , then
AfB=A *A *A ...*A
where n-B.

3+5=3*3*3*3*3=243

If B is an i n t e g e r <O t h e n
A t B = l / ( A *A *A
A ) where n=B

3+-5=1/243

I f B is a decimal (non-integer)
and A>O, then AtB=EXP(B*LOG(A))

2+3.6=12.1257

I f B i s a p o s i t i v e or n e g a t i v e
decimal (non-integer) and A<O
program aborts due t o f a t a l error.

-3t2.6 i s i l l e g a l .
F a t a l error message
EM p r i n t e d .

...* ,

2-5

CHAPTER 3
OS/8

INDUSTRIAL BASIC STATEMENTS

Example Program i s i n c l u d e d a t t h i s p o i n t as an
i l l u s t r a t i o n o f t h e format of an OS/8 I n d u s t r i a l BASIC program, t h e
ease i n running it, and t h e t y p e of o u t p u t t h a t may be produced. T h i s
program and i t s r e s u l t s are f o r t h e m o s t p a r t s e l f - e x p l a n a t o r y .
Following s e c t i o n s and c h a p t e r s c o v e r t h e program s t a t e m e n t s and
system commands used i n OS/8 I n d u s t r i a l BASIC programming.
The f o l l o w i n g

10 RE#
PROGRAM TO TAKE AVERAGE OF
15 REN
STUDEiVT GRADES A U D CLASS GHADES
20 P R I N T "HOW RIIAt'JY STUDE'JTS, .(OW YAW GRADES PER STUDEYT";
30 I ~ U P U T A i B
40 L E T 1 = 0
50 FOR J=I TO A-1
55 L E T V=O
60 P R I N T "STUDEYT NUMBER = " t J
7 5 P R I N T "EYTER GRADES"
76 L E T D=J
80 FOR K = D TO D + < 8 - 1 )
8 1 I'VPUT G
82 LET V=V+G
8 5 NEXT K
9 0 L E T V=V/B
9 5 PRIiVT "AVERAGE GRADE = * ' J V
9 6 PRINT
99 L E T Q=Q+V
100 NEXT J
101 P R I N T
102 P R I N T
103 P R I N T "CLASS AVERAGE =";Q/A
104 STOP
105 END
READY
RUNYH

HOW 1vlAs4Y GRADES PER STUDEt'JT?5,4

HOW YANY S T U D W T S ,

STUDENT dUMBER
W T E R GRADES

? 78

?8 6
?88
?74
AVERAGE GRADE = 8 1 5
STUDENT NUMBER =
EPJTER GRADES

? 59

?8 6
?70

?87

AVERAGE GRADE = 75.5

3-1

STUDENT s\)UHBER =
EVTER GRADES

?58
? 64
?75
?8 0
AVERAGE GRADE = 6 9 - 2 5
STUDENT VUMBER
ENTER GRADES

?88
?9 2

?8 5
?79
AVERAGE GRADE = 8 6
STUDENT NUHBER =
EVTER GRADES
? 60
?78

?8 5
?4 0

AVERAGE GRADE = 7 5 . 7 5

CLASS AVERAGE = 7 - 7 - 6

3.1

STATEMENT NUMBERS

A program i s made up o f s t a t e m e n t s .
Each l i n e of t h e program b e g i n s
w i t h a l i n e number of 1 t o 5 d i g i t s t h a t s e r v e s to i d e n t i f y t h e l i n e
as a s t a t e m e n t . The l a r g e s t allowable l i n e number i s 99999.
Line
numbers s e r v e t o s p e c i f y t h e order i n which t h e s e s t a t e m e n t s are t o b e
performed.
Before t h e program i s r u n , OS/8 I n d u s t r i a l BASIC s o r t s o u t
and edits t h e program, p u t t i n g t h e s t a t e m e n t s i n t o t h e order s p e c i f i e d
by their l i n e numbers; t h u s , the program s t a t e m e n t s can b e t y p e d i n
any order, as long as each s t a t e m e n t i s p r e f i x e d w i t h a l i n e number
i n d i c a t i n g i t s p r o p e r sequence i n t h e order o f e x e c u t i o n .
Each
s t a t e m e n t starts a f t e r i t s l i n e number w i t h an E n g l i s h word ( e x c e p t
t h e LET s t a t e m e n t where 'LET' i s o p t i o n a l ) which d e n o t e s t h e t y p e o f
statement.
Unlike program s t a t e m e n t s , system commands are n o t
preceded by l i n e numbers and are e x e c u t e d immediately a f t e r t h e y are
( R e f e r t o Chapter 9 f o r a f u r t h e r d e s c r i p t i o n o f commands.)
typed i n .
Spaces have no s i g n i f i c a n c e i n BASIC programs or commands, e x c e p t i n
messages or literal s t r i n g s which are p r i n t e d out, and i n line
numbers.
Thus, s p a c e s may be used t o modify a program and make it
more readable.

A common programming p r a c t i c e i s t o number l i n e s by f i v e s or t e n s ,

t h a t a d d i t i o n a l l i n e s may be i n s e r t e d i n a program w i t h o u t t h e
n e c e s s i t y o f renumbering l i n e s a l r e a d y p r e s e n t .
Renumbering a program
can be accomplished by u s i n g the RESEQ program described i n Chapter 9 ,
s e c t i o n 9.1.2.

3-2

M u l t i p l e s t a t e m e n t s may be placed on a s i n g l e l i n e by s e p a r a t i n g each
s t a t e m e n t from t h e preceding s t a t e m e n t w i t h a b a c k s l a s h (SHIFT/L).
For example:

10 A=5\B=. 2\C=3\PRINT "ENTER DATA"

All of the s t a t e m e n t s i n l i n e 1 0 w i l l be executed before BASIC
continues to t h e next line.
Only one s t a t e m e n t number a t t h e
beginning of t h e e n t i r e l i n e i s necessary.
However, it should be
remembered t h a t program c o n t r o l cannot b e t r a n s f e r r e d t o a s t a t e m e n t
w i t h i n a l i n e , b u t o n l y t o t h e f i r s t s t a t e m e n t of t h e l i n e i n which it
i s contained.
NOTE

U s e r process i n t e r r u p t r o u t i n e s

only
Le.

when

w i l l be e n t e r e d
the mainline e n c o u n t e r s a l i n e number.

loo

FOR 1-1 TO ~ O O O O \ N E X T I

does n o t allow u s e r process i n t e r r u p t r o u t i n e s t o
be e n t e r e d w h i l e e x e c u t i n g t h i s l i n e because t h e
e n t i r e loop does n o t c o n t a i n l i n e numbers.
100

105

FOR 1-1 TO 10000
NEXT I

w i l l allow u s e r process i n t e r r u p t r o u t i n e s
executed w h i l e p r o c e s s i n g t h e loop.

3.2

REMARK

THE COMMENTING STATEMENT

The REM or REMARK s t a t e m e n t allows t h e programmer t o

i n s e r t comments
remarks i n t o a program without t h e s e comments a f f e c t i n g execution.
The OS/8 I n d u s t r i a l BASIC compiler i g n o r e s e v e r y t h i n g between REM and
the end of t h e l i n e .
The form is:

( l i n e number) REM (message)
I n t h e Example Program, l i n e s 1 0 and 15 are REMARK s t a t e m e n t s
I t is o f t e n u s e f u l t o p u t t h e name
d e s c r i b i n g what t h e program does.
of the program and information r e l a t i n g t o i t s use a t the beginning
where it i s a v a i l a b l e for f u t u r e r e f e r e n c e .
R e m a r k s throughout the
body of a long program w i l l h e l p subsequent debugging by e x p l a i n i n g
t h e purpose of each s t a t e m e n t w i t h i n t h e program.

3- 3

3.3

3.3.1

STATEMENTS FOR TERMINATING A PROGRAM

END

The END s t a t e m e n t ( l i n e 140 i n t h e Example Program) should be t h e l a s t

s t a t e m e n t of t h e e n t i r e program.

The form is:

( l i n e number) END
NOTE
END statement must be t h e
last
s t a t e m e n t i n t h e program. A program i s
t e r m i n a t e d when an END s t a t e m e n t is
executed,
I n real t i m e o p e r a t i o n s a
program should never e x e c u t e e i t h e r an
END or a STOP.

3.3.2

STOP

The STOP s t a t e m e n t is used synonymously w i t h t h e END s t a t e m e n t t o
t e r m i n a t e e x e c u t i o n ; b u t while END o c c u r s o n l y once a t t h e end of a
program, STOP may occur any number of t i m e s .
The format o f t h e STOP
s t a t e m e n t is:
( l i n e number) STOP
This s t a t e m e n t s i g n a l s t h a t e x e c u t i o n i s t o be
p o i n t i n t h e program where it i s encountered.

3.4

LET

terminated

that

-- THE ASSIGNMENT STATEMENT

The Assignment (mT) s t a t e m e n t i s probably t h e m o s t commonly used OS/8
I n d u s t r i a l BASIC s t a t e m e n t and is used whenever a v a l u e i s t o be
assigned t o a variable.
I t i s of t h e form:

( l i n e number) LET x = e x p r e s s i o n
where x r e p r e s e n t s a v a r i a b l e , and t h e e x p r e s s i o n i s e i t h e r a number,
a n o t h e r v a r i a b l e , or an a r i t h m e t i c e x p r e s s i o n . The word " U T " i s
o p t i o n a l ; t h u s t h e f o l l o w i n g s t a t e m e n t s are treated t h e same:
100

LET A=AfB+10

110

LET L=L+1

100

A=AfB+10

110

L=L+1

The LET s t a t e m e n t is n o t s t r i c t l y an e q u a l i t y .
LET means " e v a l u a t e
t h e e x p r e s s i o n t o t h e r i g h t of t h e e q u a l s i g n and a s s i g n t h i s v a l u e t o
t h e v a r i a b l e on t h e left." Thus, t h e s t a t e m e n t L=L+l means "set L
e q u a l t o a value one g r e a t e r t h a n it w a s before."

3-4

3.5

INPUT/OUTPUT STATEMENTS AND FUNCTIONS

Input/output s t a t e m e n t s allow t h e u s e r t o b r i n g data i n t o
and o u t p u t r e s u l t s o r data a t any t i m e d u r i n g execution.

3.5.1

program

The INPUT Statement

The INPUT s t a t e m e n t i s used when d a t a i s t o be s u p p l i e d by t h e u s e r
f r o m t h e t e r m i n a l keyboard while a program i s e x e c u t i n g and i s of t h e
form:
( l i n e number) INPUT x l , x2,...,xn
where x l through xn r e p r e s e n t v a r i a b l e names.
25

For example:

INPUT A

When t h i s s t a t e m e n t o c c u r s i n Mainline Mode, t h e u s e r w i l l be prompted
w i t h a q u e s t i o n mark and while w a i t i n g f o r i n p u t , u s e r p r o c e s s
i n t e r r u p t s e r v i c e r o u t i n e s may execute.
I f it o c c u r s i n t h e u s e r
p r o c e s s i n t e r r u p t service r o u t i n e , t h e u s e r w i l l be prompted w i t h an
exclamation mark followed by a q u e s t i o n mark and t h e system w i l l w a i t
for
i n p u t completion b e f o r e p r o c e s s i n g any o t h e r u s e r p r o c e s s
i n t e r r u p t routine.
NOTE

I f an i n p u t statement o c c u r s i n t h e u s e r p r o c e s s
interrupt
s e r v i c e r o u t i n e w h i l e t h e u s e r is
e n t e r i n g i n p u t i n t h e Mainline Mode, t h e t e x t i s
lost t o the l a s t terminator. After t h e request is
f u l f i l l e d f o r t h e u s e r process i n t e r r u p t s e r v i c e
r o u t i n e t h e mainline r e q u e s t w i l l be r e i s s u e d .
The following r u l e s apply t o t h e u s e of t h e I N P U T statement.
Rule
1.

The following c h a r a c t e r s are recognized
i n p u t t i n g numeric data:

acceptable

when

+ or - s i g n

d i g i t s 0 through 9
the letter E
l e a d i n g spaces (ignored)
( f i r s t decimal p o i n t )

Terminators are c a r r i a g e r e t u r n or coma.
A l l o t h e r c h a r a c t e r s cause t h e remaining

f i e l d t o be ignored.
10

INPUT A,B,C,D,E

3-5

characters

the

RU"H

?10,32A16,8
?5,6
READY

I n t h e above example, A=10, B-32,

C=8, -5,

and E = 6 .

i n p u t t i n g numeric d a t a , t w o t e r m i n a t o r s
read
in
succession imply t h a t t h e d a t a between t h e terminators i s 0.

When

..
.

INPUT AIBIC,D,E

RU"H

?5,10,,12,15
READY

I n t h e above example A=5, B=lO, C=O, OC12, and E=15.
3.

I n response t o an INPUT s t a t e m e n t t h e user can p r o v i d e more
d a t a than i s r e q u e s t e d by t h e I N P U T statement.
The remaining
or unused d a t a i s saved f o r subsequent u s e by t h e n e x t INPUT
statement.
The q u e s t i o n mark ( ? ) i s n o t p r i n t e d u n t i l t h e
program i s out of d a t a .

When

inputting
string
data,
all
characters,
except
are recognized as part o f the s t r i n g . See
Chapter 7 f o r f u r t h e r i n f o r m a t i o n r e l a t i n g t o s t r i n g s .

terminators,
-

l i n e f e e d i s recognized as p a r t of t h e
t h e r e f o r e is s t o r e d i n t h e t e x t b u f f e r .

3.5.2

s t r i n g d a t a , and

The PRINT Statement

3.5 2 1 General
The PRINT

comments,
terminal.

statement is used t o o u t p u t r e s u l t s
values of variables, or p l o t p o i n t s
The format is:

of computations,
o f a graph on the

(line number) PRINT expression

When used w i t h o u t an e x p r e s s i o n , a blank l i n e w i l l b e o u t p u t on t h e
terminal.
For more complicated uses, t h e t y p e o f e x p r e s s i o n and t h e
t y p e o f format c o n t r o l c h a r a c t e r s (comma or semicolon) f o l l o w i n g t h e
word PRINT determines which formats w i l l b e c r e a t e d .

In order to have the computer print out the r e s u l t s of a computation,
or t h e value o f a variable a t any p o i n t i n t h e program, t h e u s e r t y p e s

3-6

t h e l i n e number, PRINT, and t h e v a r i a b l e name(s) s e p a r a t e d by a format
control c h a r a c t e r , i n t h i s case, commas:
5

10
15

A=16\B=5\C=4
PRINT A,C+B,SQR(A)
END

The PRINT s t a t e m e n t may a l s o be used t o o u t p u t a message or l i n e of
text.
The d e s i r e d message i s simply placed i n q u o t a t i o n marks i n t h e
PRINT s t a t e m e n t as follows:
PRINT "THIS IS A TEST"

When l i n e 10 i s encountered d u r i n g e x e c u t i o n , t h e
printed :

following

will

THIS IS A TEST
A message may be combined with

the

result

calculation

v a r i a b l e as follows :
PRINT "AMOUNT PER PAYMENT =";R

Assuming R=344.961 when l i n e 80 i s encountered d u r i n g e x e c u t i o n ,
w i l l be o u t p u t as:

this

AMOUNT PER PAYMENT = 344.961
THE PRINT s t a t e m e n t can also cause a c o n s t a n t t o
console
For example :

printed

the

P R I N T 1.234,SQR(10014)

w i l l cause t h e following t o be o u t p u t a t e x e c u t i o n t i m e :
1.234

100.07

Any a l g e b r a i c e x p r e s s i o n i n a PRINT s t a t e m e n t w i l l be e v a l u a t e d u s i n g
Numbers w i l l be p r i n t e d according
t h e c u r r e n t value of t h e v a r i a b l e s .
t o t h e format s p e c i f i e d i n Chapter 2 and i n paragraph 3.5.2.3.

3.5.2.2

Format Control C h a r a c t e r s

I n O S / 8 I n d u s t r i a l BASIC, a t e r m i n a l l i n e i s formatted i n t o f i v e f i x e d
zones ( c a l l e d p r i n t zones) of 14 columns each. A program such a s :
5
10
15

A=2.3\B=21\C=156.75\D=l.l34\E=23.4
PRINT A,B,C,D,E
END

where t h e c o n t r o l c h a r a c t e r comma (,)
i s used t o
v a r i a b l e s i n t h e P R I N T s t a t e m e n t , w i l l cause t h e
v a r i a b l e s t o be p r i n t e d using a l l f i v e zones.
RU"H
2.3

156.75

3-7

1.134

separate the
v a l u e s of t h e

23.4

14 column+

14 columnsk 14 columns+ 14 column+

14 columns

READY

I t i s n o t n e c e s s a r y t o use t h e s t a n d a r d f i v e zone format f o r output.
c a u s e s t h e t e x t o r d a t a t o be
The c o n t r o l character semicolon (;)
o u t p u t immediately a f t e r t h e l a s t c h a r a c t e r p r i n t e d .
The f o l l o w i n g example program i l l u s t r a t e s
c h a r a c t e r s i n PRINT s t a t e m e n t s

the

use

the

control

10 READ A0 B> C
20 P R I N T A D B D C D A ~ ~ D B ~ ~ J C ~ ~

30 P R I N T
40 P R I N T Af B; Cf A t 23 B t 2; C t 2
50 DATA 4,506
60 Et’lD
READY
RWVH
5

READY

A s t h i s example i l l u s t r a t e s , when more t h a n f i v e v a r i a b l e s are l i s t e d
i n t h e PRINT s t a t e m e n t , OS/8 I n d u s t r i a l BASIC a u t o m a t i c a l l y moves t h e
s i x t h number t o t h e beginning of t h e n e x t l i n e .

3.5.2.3

P r i n t i n g Numbers

For any format ( i n t e g e r , decimal, or
p r i n t s numbers i n t h e form:

E-type)

OS/8

Industrial

BASIC

s i g n number space
where s i g n is e i t h e r minus (-1
always t r a i l s t h e number.

or blank ( f o r p l u s ) and a

READY
10 A= 6 4 \ B = 32\C=72
20 P R I N T A l B i C
2 1 E,AD
RUWH
64 - 3 2 7 2

3-8

blank

space

3.5.2.4

PRINT Used With INPUT

Another use o f t h e PRINT statement i s t o combine it w i t h an
s t a t e m e n t so a s t o i d e n t i f y t h e d a t a expected t o be e n t e r e d .
example, c o n s i d e r t h e following program:

READY

10 REY
PROGRAM TO C W P U T E I N T E R E S T PAYYEVTS
20 P R I N T "I NTEREST I N PERCEiVT";
25 INPUT J
26 LET J = J / 1 0 0
30 P R I N T "AMOU'JT OF LOA,Vs'3
35 IVPUT A
40 P R I N T "NUMBER OF YEARS";
45 1"JPUT N
50 P R I N T "NUMBER OF PAYgENTS PER YEAH";
55 INPUT
60 L E T N=N*M
6 5 L E T I=J/M
70 LET B=l+I
7 5 L E T R=A*I / C 1- l / B t N )
78 P R I N T
8 0 P R I N T "AMOUNT PER PAY;VIEiVT ="SR
8 5 P R I N T "TOTAL I N T E R E S T
=*'; H*N-A
9 0 LET B=A
9 5 PRINT " INTEREST
APP T O P R I N
BALANCE"
100 L E T L=B*I
1 1 0 L E T P=R-L
120 L E T B=B-P
130 PRI INT L DPDB
140 I F B>=R G O TO 1 0 0
150 P R I N T B*IDR-B*I
160 P R I N T "LAST PAYMEVT =";B*I+B
200 END

READY
RUNNH
INTEREST I N PERCENT?9
AMOUNT OF LOAN?2500
NUMBER OF YEARS?P
NUMBER OF PAYMENTS PER YEAR?4
AMOUNT PER PAYMENT = 344.965
TOTAL I N T E R E S T
= 259.724
INTEREST
APP TO PRIN
BALAVCE
56.25
288 7 1 5
2211.28
49.7539
29 5.2 1 2
19 16.07
43.1116
301.8 54
1614.22
36.3199
308.645
1385.57
29. 37 54
31 5. 59
989 e982
22.2746
322.69 1
667. 29 1
150 0141
329 9 5 1
337.34
70 59015
337.37 5
LAST PAYMENT = 3 4 4 . 9 3
READY

3-9

INPUT
As an

As can be n o t i c e d i n t h i s example, t h e q u e s t i o n mark i s

grammatically
u s e f u l i n a program i n which s e v e r a l v a l u e s are t o be i n p u t by
allowing t h e programmer t o formulate a v e r b a l q u e s t i o n which t h e i n p u t
v a l u e w i l l answer.

3.5.3

The TAB(X) Function

The TAB f u n c t i o n , which may o n l y be used i n a PRINT s t a t e m e n t , allows
t h e u s e r t o p o s i t i o n t h e p r i n t i n g of c h a r a c t e r s anywhere on t h e
t e r m i n a l l i n e ( o r o t h e r p r i n t i n g d e v i c e l i n e when used w i t h PRINT#,
see Chapter 1 0 ) . P r i n t p o s i t i o n s can be thought of as b e i n g numbered
The form of t h i s
from 1 t o 72 across t h e t e r m i n a l from l e f t t o r i g h t .
f u n c t i o n is:
TAB ( X )

where t h e argument X r e p r e s e n t s t h e p o s i t i o n (from 1 t o 7 2 columns
a v a i l a b l e on t h e t e r m i n a l ) i n which t h e n e x t character w i l l be typed.
Each t i m e t h e TAB f u n c t i o n i s used i n a PRINT s t a t e m e n t , p o s i t i o n s are
counted from t h e beginning of t h e l i n e , n o t from t h e c u r r e n t p o s i t i o n
of t h e p r i n t i n g head.
F o r example, t h e TAB f u n c t i o n i n t h e f o l l o w i n g
program c a u s e s t h e c h a r a c t e r "/" t o be p r i n t e d a t 24 e q u a l l y spaced
p o s i t i o n s along t h e l i n e .
10
20

30
40

FOR K=3 TO 72 STEP 3
PRINT TAB(K) in/";
NEXT K
END

I f t h e argument X i n t h e TAB f u n c t i o n i s less t h a n t h e c u r r e n t
p o s i t i o n of t h e p r i n t i n g head, p r i n t i n g i s started a t t h e c u r r e n t
position.
I f t h e argument X i s g r e a t e r t h a n 7 2 ( t h e number o f columns
a v a i l a b l e i n an o u t p u t l i n e ) , a carriage r e t u r n - l i n e feed is e x e c u t e d
and p r i n t i n g resumes a t p o s i t i o n 1.

3.5.4

The P N T ( X ) Function

an a d d i t i o n a l f u n c t i o n , P N T ( X ) ,
to
i n c r e a s e i n p u t / o u t p u t f l e x i b i l i t y . The f u n c t i o n i s p r i m a r i l y used f o r
o u t p u t t i n g non-printing c h a r a c t e r s such as t h e " b e l l " , b u t can be used
f o r m o r e s o p h i s t i c a t e d a p p l i c a t i o n s . The P N T ( X ) f u n c t i o n , l i k e t h e
TAB(X) f u n c t i o n , may o n l y be used i n either a PRINT or PRINT#
statement.
The form of t h e f u n c t i o n is:
OS/8 I n d u s t r i a l BASIC provides

PNT ( X )

where t h e argument X r e p r e s e n t s t h e decimal v a l u e of t h e
c h a r a c t e r t o be output.
For example, t h e statement:
10

PRINT "X=";3.14159;PNT(13) ;TAB(14) ;"/"

3-10

7-bit

ASCII

w i l l p r i n t t h e s l a s h (/) on t o p of t h e e q u a l s i g n a f t e r e x e c u t i n g
c a r r i a g e r e t u r n (CR=13 1 and a TAB t o column 2 as shown below:

X 9,3.14159
Notice t h a t a TAB(14) i s r e q u i r e d s i n c e O S / 8 I n d u s t r i a l BASIC
remembers the p r i n t head t o be a t column 1 2 a f t e r t h e carriage r e t u r n
(11 columns f o r X= 3.14159
and 1 column for t h e PNT f u n c t i o n ) .
A
tab t o column 2 a f t e r t h e carriage r e t u r n p r o v i d e s a t o t a l of 1 4
columns. The PNT(13) carriage r e t u r n does n o t z e r o t h e column count
b u t , i n f a c t , adds t o t h e column count,
(This example may n o t work on
some t e r m i n a l s . )

3.6

THE READ AND DATA STATEMENTS

READ and DATA s t a t e m e n t s are used t o provide data t o a program.
One
s t a t e m e n t is never used without t h e other. T h e form of t h e READ
s t a t e m e n t is:

( l i n e number) READ xl,x2,. , ,xn
where x l through xn r e p r e s e n t v a r i a b l e names.
10

For example:

READ A,B,C

A, B, and C are v a r i a b l e s t o which v a l u e s w i l l be assigned.
Variables
i n a READ s t a t e m e n t must be separated by commas. FtEAD s t a t e m e n t s are

g e n e r a l l y placed a t the beginning of a program, b u t must a t least
l o g i c a l l y occur before t h a t p o i n t i n t h e program where t h e v a l u e i s
r e q u i r e d f o r some computation.
Values which w i l l be assigned t o t h e v a r i a b l e s i n a READ s t a t e m e n t are
s u p p l i e d i n a DATA s t a t e m e n t o f t h e form:

( l i n e number) DATA x1,x2, , ,xn
where x l through xn r e p r e s e n t values.
The v a l u e s must be separated by
commas and occur i n the same order as t h e v a r i a b l e s which are l i s t e d
i n t h e corresponding READ statement. A DATA s t a t e m e n t a p p r o p r i a t e for
t h e preceding READ s t a t e m e n t is:
70

DATA 1,2,3

Thus, a t e x e c u t i o n t i m e A = l , B-2, and C=3.
The DATA s t a t e m e n t is u s u a l l y placed a t t h e end of a program
(before
t h e END s t a t e m e n t ) where i t i s e a s i l y a c c e s s i b l e t o t h e programmer
s h o u l d he wish t o change the v a l u e s ,
A READ s t a t e m e n t may have more or f e w e r variables t h a n there are
v a l u e s i n any one DATA statement.
The READ s t a t e m e n t c a u s e s OS/8
I n d u s t r i a l BASIC t o search a l l a v a i l a b l e DATA s t a t e m e n t s i n the order

their l i n e numbers u n t i l v a l u e s are found f o r each v a r i a b l e i n t h e
A second READ s t a t e m e n t w i l l begin r e a d i n g v a l u e s where t h e
first stopped. I f a t some p o i n t i n the program an a t t e m p t i s made t o
read data which is n o t p r e s e n t , OS/8 I n d u s t r i a l BASIC w i l l s t o p and

READ.

3-11

p r i n t t h e f o l l o w i n g message a t t h e console:
DA AT LINE YYYYY

where YYYYY i n d i c a t e s t h e l i n e which caused t h e error.

3.7

RESTORE

If it is desired t o use t h e same data more t h a n once i n a program, t h e
s t a t e m e n t w i l l make it p o s s i b l e t o r e c y c l e through t h e DATA
l i s t beginning w i t h t h e f i r s t DATA statement. The RESTORE s t a t e m e n t
is of t h e form:
RESTORE

( l i n e number) RESTORE
An example of

i t s use follows:

READ B,C,D

55
60

RESTORE
READ E,F,G

100

DATA 6,3,4,7,9,2

END

The READ s t a t e m e n t s i n l i n e s 15 and 60 w i l l both read t h e f i r s t three
data v a l u e s provided i n l i n e 80,
( I f t h e RESTORE s t a t e m e n t had n o t
been i n s e r t e d b e f o r e l i n e 60, then t h e second READ would pick up data
i n l i n e 80 s t a r t i n g w i t h t h e f o u r t h v a l u e , )

The programmer may, i f h e chooses t o do so, use t h e same v a r i a b l e
t h e second t i m e through t h e data, s i n c e t h e v a l u e s are b e i n g
read as though f o r t h e f i r s t t i m e .
I n order t o s k i p unwanted v a l u e s ,
t h e programmer may i n s e r t replacement, or dummy v a r i a b l e s . Consider:

names

1 REN
PROGRAM T O I L L U S T R A T E USE OF RESTORE
20 READ N
25 P R I N T "VALUES OF X ARE:"
30 FOR L = l TO N
40 READ X
50 P R I N T X 0
60 NEXT I
7 0 RESTORE
185 P R I N T
190 P R I N T "SECOND L I S T OF X VALUES"
200 P R I N T "FOLLOWING RESTORE STATEMENT: "
210 FOR 1 = 1 TO N

3-12

220 R E A D X
230 P R I N T X,
240 NEXT I
250 DATA 4,1, 2
251 D A T A 3,4

300 F 3 D

READY
RUVNH
V A L U E S OF X ARE:
1
2
3
SECOND L I S T OF X V A L U E S
F O L L O W I N G R E S T O R E STATEMENT:
4
1
2
READY

The second t i m e t h e data values are read, t h e f i r s t X p i c k s up t h e
v a l u e o r i g i n a l l y assigned t o N i n l i n e 20, and as a r e s u l t , OS/8
I n d u s t r i a l BASIC p r i n t s :
4

To circumvent t h i s , t h e programmer could i n s e r t a dummy v a r i a b l e which
would p i c k up and store t h e f i r s t v a l u e , b u t would n o t be r e p r e s e n t e d
i n t h e PRINT s t a t e m e n t , i n which c a s e t h e o u t p u t would be t h e same
each t i m e through the list.

3.8

CONTROL STATEMENTS

C e r t a i n c o n t r o l s t a t e m e n t s cause t h e e x e c u t i o n of a program t o jump t o
a d i f f e r e n t l i n e either u n c o n d i t i o n a l l y o r depending upon some
c o n d i t i o n w i t h i n the program.
The following s t a t e m e n t s g i v e t h e
programmer c a p a b i l i t i e s i n t h i s area.

3.8.1

GOTO

The GOTO (or GO TO) s t a t e m e n t i s an u n c o n d i t i o n a l s t a t e m e n t used t o
direct program c o n t r o l either forward o r backward i n a program. The
form of t h e GOTO s t a t e m e n t is:

( l i n e number) GOTO n
where n r e p r e s e n t s a s t a t e m e n t number. When t h e l o g i c of t h e program
reaches t h e GOTO s t a t e m e n t , t h e s t a t e m e n t ( s ) immediately following
w i l l n o t be executed; i n s t e a d e x e c u t i o n is t r a n s f e r r e d t o t h e
s t a t e m e n t beginning w i t h t h e l i n e number i n d i c a t e d .
The following program never reaches t h e END s t a t e m e n t ; it does a READ,
p r i n t s something, and jumps back t o t h e READ v i a a GOTO statement.
It
attempts t o do t h i s o v e r and over u n t i l it runs o u t of d a t a , which i s
sometimes an a c c e p t a b l e , though n o t a d v i s a b l e , way t o end a program.

3-13

READY

PROGRAN ENDING WITH ERROR
1 1 REM
MESSAGE WHEN OUT OF DATA
20 READ X

10 REM

25 PRINT "X="3X,"Xt2="3Xt2
30 G O TO 20
35 DATA 1 D 5~ 1 0 ~ 1
SD20r 25
40 EVD
READY
RUNNH

x= 1
x= 5
x= 10
x- 1s
x= 20
X=

Xt2= 1
Xt2= 25
Xt2= 100
X t 2 = 225
Xt2= 400
Xt2= 625

DA AT L I N E 00020
READY

3.8.2

IF-THEN

and IF-GOT0

I f a program r e q u i r e s t h a t t w o v a l u e s be compared a t some p o i n t ,
c o n t r o l of program e x e c u t i o n may be d i r e c t e d t o d i f f e r e n t procedures
depending upon t h e r e s u l t of t h e comparison.
I n computing, v a l u e s are
l o g i c a l l y tested t o see whether t h e y are e q u a l t o , g r e a t e r t h a n , or
less t h a n a n o t h e r v a l u e , or p o s s i b l y a combination of t h e t h r e e . T h i s
i s accomplished by u s e of t h e r e l a t i o n a l o p e r a t o r s d i s c u s s e d i n
Chapter 2.
IF-THEN and IF-GOT0
s t a t e m e n t s a l l o w t h e programmer t o t e s t t h e
relationship
between
two
variables,
numbers, or e x p r e s s i o n s .
Providing t h e r e l a t i o n s h i p d e s c r i b e d i n t h e I F s t a t e m e n t is t r u e a t
the p o i n t it is tested, c o n t r o l w i l l t r a n s f e r t o t h e l i n e number
specified.
I f t h e r e l a t i o n s h i p described i n t h e I F s t a t e m e n t i s n o t
t r u e a t the p o i n t it is tested, c o n t r o l w i l l t r a n s f e r t o t h e l i n e
f o l l o w i n g the I F s t a t e m e n t . The s t a t e m e n t s are of t h e form:
GOTO

( l i n e number)IF v l < r e l a t i o n > v2

THEN

where v l and v2 r e p r e s e n t v a r i a b l e names, numbers, or e x p r e s s i o n s , and
x r e p r e s e n t s a l i n e number.
The u s e of e i t h e r THEN or GOTO i s
acceptable.

I f t h e f o l l o w i n g example, t h e v a l u e o f t h e v a r i a b l e A
remains t h e same depending on A's r e l a t i o n t o B.
100
110

I F A>B THEN 120
A=AtB-1

120

C=A/D

3-14

changed

NOTE

When using non-integer arithmetic in the
IF-THEN statement, the test for equality
may not always be appropriate due to the
nature of the floating-point arithmetic
used by the computer.
To avoid this
problem, the programmer should either
avoid using non-integer arithmetic in
fractional values
less
than
the
tolerance desired. IF-THEN statements
that
test
the running variable in
FOR-NEXT
loops (see Chapter 4 ) are
particularly sensitive to this problem.
For example:
TO 5 STEP .1

FOR A=-5

20
30
40
50

IF A=O THEN 50

NEXT A

STOP
PRINT "EQUAL TO ZERO"
END

The above margin will never go to line 50.

3-15

CHAPTER 4

LOOPS

Frequently programmers are i n t e r e s t e d i n w r i t i n g a program i n which
one o r more p o r t i o n s are executed a number of t i m e s , u s u a l l y w i t h
To w r i t e t h e s i m p l e s t program i n which
s l i g h t v a r i a t i o n s each t i m e .
t h e p o r t i o n of t h e program t o be r e p e a t e d i s w r i t t e n j u s t once, a loop
is used. A loop i s a block of i n s t r u c t i o n s t h a t t h e computer e x e c u t e s
repeatedly
u n t i l a specified terminal condition is m e t .
OS/8
I n d u s t r i a l BASIC provides t w o s t a t e m e n t s t o s p e c i f y a loop: FOR and
NEXT.

4.1

FOR AND NEXT STATEMENTS

The FOR s t a t e m e n t i s o f t h e form:
( l i n e number) FOR v=xl TO x2 STEP x3
where v r e p r e s e n t s a v a r i a b l e name, and x l , x2, and x3 a l l r e p r e s e n t
expressions
( a numerical v a l u e , v a r i a b l e name, o r mathematical
expression). v i s termed t h e index, x l t h e i n i t i a l v a l u e , x2 t h e
For example:
t e r m i n a l value, and x3 t h e incremental value.
15 FOR K=2 TO 20 STEP 2
This means t h a t t h e loop w i l l be r e p e a t e d as long as K i s less t h a n or
e q u a l t o 20.
Each t i m e through t h e loop, K i s incremented by 2 , so
t h e loop w i l l be executed a t o t a l of 10 t i m e s .

variable used as an index i n a FOR s t a t e m e n t must n o t be
subscripted,
although a common u s e of loops i s t o deal w i t h
s u b s c r i p t e d v a r i a b l e s , using t h e value of t h e index as t h e s u b s c r i p t
of a p r e v i o u s l y d e f i n e d v a r i a b l e ( t h i s i s i l l u s t r a t e d i n Chapter 5 ,
s e c t i o n 5.1 concerning S u b s c r i p t e d Variables)

The NEXT s t a t e m e n t is of t h e form:
( l i n e number) NEXT v

and s i g n a l s t h e end of the loop. When e x e c u t i o n of t h e loop r e a c h e s
t h e NEXT s t a t e m e n t , t h e computer adds t h e STEP v a l u e t o t h e index and
checks t o see i f t h e index i s less than or e q u a l t o t h e t e r m i n a l
I f t h e value o f t h e index
value.
I f so, t h e loop i s executed again.
exceeds t h e t e r m i n a l v a l u e , c o n t r o l f a l l s through t h e loop t o t h e
s t a t e m e n t following t h e NEXT s t a t e m e n t , w i t h t h e v a l u e of t h e i n d e x
e q u a l l i n g t h e value it w a s assigned t h e f i n a l t i m e through t h e loop.
If t h e STEP value i s omitted, a value of +1 is assumed.
Since +1 i s
t h e u s u a l STEP value, t h a t p o r t i o n of t h e s t a t e m e n t is f r e q u e n t l y
omitted.
The STEP value may a l s o be a n e g a t i v e number.

The following example i l l u s t r a t e s t h e u s e
executed

loops.

This

loop

10 t i m e s : the value of I i s 1 0 when control leaves t h e loop.
+1i s t h e assumed STEP value.

4-1

READY
10 FOR 1 = 1 T O 10
20 NEXT I
30 P R I N T I
40 END
RUNNH
10

READY

I f l i n e 1 0 had been:
1 0 FOR 1110

TO 1 STEP -1

t h e v a l u e p r i n t e d by t h e computer would be 1.
As i n d i c a t e d earlier, the

numbers used i n the FOR s t a t e m e n t are
expressions:
t h e s e e x p r e s s i o n s are e v a l u a t e d upon first e n c o u n t e r i n g
t h e loop. While the index, i n i t i a l , t e r m i n a l , and STEP v a l u e s may be
changed w i t h i n t h e loop, t h e v a l u e a s s i g n e d t o t h e i n i t i a l e x p r e s s i o n
remains as o r i g i n a l l y d e f i n e d u n t i l t h e t e r m i n a l c o n d i t i o n i s reached.
T o i l l u s t r a t e this p o i n t ,
c o n s i d e r the l a s t example program.
The
v a l u e of I ( i n l i n e 1 0 ) can be s u c c e s s f u l l y changed as follows:
10
15

FOR 1-1 TO 10
LET I=10

NEXT I

The loop w i l l be executed o n l y once s i n c e t h e v a l u e 1 0 has been
reached by t h e v a r i a b l e I and t h e t e r m i n a l c o n d i t i o n i s s a t i s f i e d .
I f t h e value of the c o u n t e r variable i s o r i g i n a l l y set e q u a l t o t h e
t e r m i n a l v a l u e , the loop w i l l e x e c u t e once, r e g a r d l e s s of t h e STEP
value.
I f t h e s t a r t i n g v a l u e i s beyond t h e - t e r m i n a l v a l u e , t h e loop
w i l l n e v e r e x e c u t e because an i n i t i a l check is made of t h e s t a r t i n g
The f o l l o w i n g
and t e r m i n a l v a l u e s b e f o r e t h e loop i s executed.
s t a t e m e n t is executed b u t t h e loop it d e s c r i b e s would n e v e r be
executed :
1 0 FOR I s 1 0 TO 20 STEP -2

I t is possible t o e x i t from a FOR-NEXT loop w i t h o u t t h e index r e a c h i n g
C o n t r o l may o n l y t r a n s f e r
t h e t e r m i n a l value v i a an I F statement.
i n t o a loop which h a s been l e f t e a r l i e r w i t h o u t b e i n g completed,
e n s u r i n g t h a t the t e r m i n a l and STEP v a l u e s are assigned.

4.2

NESTING LOOPS

I t is o f t e n u s e f u l t o have one or more loops w i t h i n a loop.
This
t e c h n i q u e i s called n e s t i n g , and i s allowed as long as t h e f i e l d of
one loop ( t h e numbered l i n e s from t h e FOR s t a t e m e n t
to
the
corresponding NEXT s t a t e m e n t , i n c l u s i v e ) does n o t cross t h e f i e l d of

4-2

another loop.
procedures :

The following diagram

illustrates

acceptable

UNACCEPTABLE NESTING
TECHNIQUES

ACCEPTABLE NESTING
TECHNIQUES
Two Level Nestin3

(ET

FOR

G E T

Ec:o*:

Three Level Nestinq
FOR
FOR

FOR

NEXT
NEXT

NEXT
NEXT
NEXT

4-3

nesting

CHAPTER 5

LISTS AND TABLES

5.1

SUBSCRIPTED VARIABLES

I n a d d i t i o n t o s i n g l e v a r i a b l e names, O S / 8 I n d u s t r i a l BASIC a c c e p t s
another class of v a r i a b l e s called S u b s c r i p t e d V a r i a b l e s .
Subscripted
the
programmer
with
additional
computing
variables
provide
c a p a b i l i t i e s f o r handling l i s t s , tables, matrices, or any set of
related variables.
Variables are allowed one or t w o s u b s c r i p t s .
A
s i n g l e l e t t e r or a letter followed by a d i g i t forms t h e name of t h e
v a r i a b l e ; t h i s is followed by one o r t w o i n t e g e r s i n p a r e n t h e s e s and
s e p a r a t e d by commas, i n d i c a t i n g t h e p l a c e of t h a t v a r i a b l e i n t h e
list. U p t o 31 a r r a y s are p o s s i b l e i n any program, s u b j e c t o n l y t o
the amount of core space a v a i l a b l e f o r data storage. For example, a
l i s t might be described as A ( 1 ) where I goes from 1 t o 5 , as follows:

This allows the p r o g r a m e r t o r e f e r e n c e each of t h e f i v e elements i n
the l i s t A.
A t w o dimensional m a t r i x A ( 1 , J ) can be d e f i n e d i n a
similar manner, b u t t h e s u b s c r i p t e d v a r i a b l e A can be used o n l y once
(i.e., A ( 1 ) and A ( 1 , J )
cannot be used i n t h e same program). It i s
p o s s i b l e , however, t o use t h e same v a r i a b l e name as both a s u b s c r i p t e d
and an unsubscripted v a r i a b l e .
Both A and A ( 1 ) are v a l i d v a r i a b l e
names and can be used i n t h e same program.
S u b s c r i p t e d v a r i a b l e s a l l o w data t o be i n p u t q u i c k l y and e a s i l y , as
i l l u s t r a t e d i n t h e following program ( t h e index of t h e FOR s t a t e m e n t
i n l i n e s 20, 42, and 44 i s used as t h e s u b s c r i p t ) :

10 REM
PROGRAM DEMONSTARTING READING
1 1 REM
OF SUBSCRI PTED VARIABLES
15 DIM A < S ) r B ( 2 r 3 )
18 P R I N T "AC1) WHERE A= 1 TO 5: "
20 FOR 1 = 1 TO 5
25 READ AC1)
30 P R I N T A C 1 ) ;
35 NEXT I
38 P R I N T
39 P R I N T
40 P R I N T " B C I , J ) WHERE I = l TO 2:"
4 1 P R I N T '*
A N D J = 1 TO 3:*'
42 FOR 1 = 1 TO 2
43 P R I N T
44 FOR J = l TO 3
48 READ B ( 1 , J )
50 P R I N T B C I I J ) ~
55 NEXT J
5 6 NEXT I
68 DATA l a 2,3,4,5, ~ 7 , a
61 DATA 8,7r 6,5r 4, 3 s 2 , l

END

5-1

READY
RWNH
ACL) WHERE A = l TO 5:

WHERE I = 1 TO 2:

BCIJJ)

AND 3 = 1 T O 3:

READY

5.2

THE D I M STATEMENT

From t h e preceding example, i t can be s e e n t h a t t h e use o f s u b s c r i p t s
r e q u i r e s a dimension (DIM) s t a t e m e n t t o d e f i n e t h e maximum number of
elements i n t h e a r r a y .
The DIM s t a t e m e n t i s o f t h e form:
( l i n e number) D I M v ( n 1 , v (n ,m
where v i n d i c a t e s an a r r a y v a r i a b l e name and n and m are i n t e g e r
numbers i n d i c a t i n g t h e l a r g e s t s u b s c r i p t v a l u e r e q u i r e d d u r i n g t h e
program.
For example:
15

D I M A(6,lO)

The f i r s t element of e v e r y a r r a y i s a u t o m a t i c a l l y assumed t o have a
s u b s c r i p t o f zero.
Dimensioning A ( 6 , l Q ) sets up room f o r an a r r a y
w i t h 7 rows and 11 columns. T h i s m a t r i x can b e thought of as e x i s t i n g
i n t h e following form:
A

%,%

A 6,8

%,I

A 6,l

. A

%,lP

A6,18

and i s i l l u s t r a t e d i n the f o l l o w i n g program:

1 0 REM
MATRIX CHECK PROGRAM
1 5 DIM A ( 6 ~ 1 0 )
20 FOR 1 = 0 T O 6
22 L E T A C I r 0 ) = 1
25 FOR J = 0 TO f B

5-2

28 LET A < 0 r J ) = J
30 P R I N T ACI*J)J
35 NEXT J
40 PRINT
45 NEXT I
50 END
READY
RU"H
0 1
1 0
2 0
3 0
4 0
5 0
6 0

2 3 4 5 6 7 8 9 1 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0

READY

Notice that a v a r i a b l e assumes a value of z e r o u n t i l a n o t h e r v a l u e has
been assigned.
I f t h e u s e r wishes t o conserve core space by n o t
making use of t h e e x t r a v a r i a b l e s set up w i t h i n t h e a r r a y , he should
set h i s D I M s t a t e m e n t t o one less t h a n n e c e s s a r y , D I M A ( 5 , 9 ) .
This
results i n a 6 by 1 0 a r r a y which may then be r e f e r e n c e d b e g i n n i n g w i t h
t h e A(0,O) element.

More t h a n one a r r a y can be d e f i n e d i n a s i n g l e DIM statement:

This dimensions both t h e l i s t A and t h e m a t r i x B.

t o d e f i n e t h e m a x i m u m s i z e of t h e a r r a y .
A
v a r i a b l e i n s i d e t h e p a r e n t h e s e s i s n o t a c c e p t a b l e and w i l l r e s u l t i n
an error message by BASIC a t compile t i m e . The amount of u s e r core
not f i l l e d by t h e program w i l l determine t h e amount o f data t h e
computer can a c c e p t as i n p u t t o t h e program a t any one t i m e .
I n some
programs a TB error ( t o o b i g ) may occur, i n d i c a t i n g t h a t core w i l l n o t
hold an a r r a y of t h e s i z e requested.
I n t h a t e v e n t , t h e u s e r should
change h i s program t o process p a r t of t h e data i n one run and t h e rest

A number must be used

later.

NOTE
I f a subscripted variable i s not defined
by a D I M s t a t e m e n t , t h e v a r i a b l e i s
assigned an a r r a y s i z e of t e n .

5- 3

CHAPTER 6
OS/8

6.1

INDUSTRIAL BASIC FUNCTIONS AND SUBROUTINES

GENERAL INFORMATION ON OS/8

I N D U S T R I A L BASIC FUNCTIONS

I n d u s t r i a l BASIC provides a number of f u n c t i o n s , as p a r t of t h e
language, which perform c a l c u l a t i o n s .
The use of t h e s e f u n c t i o n s
e l i m i n a t e s t h e need f o r w r i t i n g s m a l l programs t o perform t h e
c a l c u l a t i o n s . Functions have a t h r e e l e t t e r c a l l name, followed by an
argument, X, which can be a number, v a r i a b l e , e x p r e s s i o n o r a n o t h e r
function.
Generally,
f u n c t i o n s may be used anywhere a number or a
v a r i a b l e is l e g a l i n a mathematical expression.
OS/8

The following OS/8
chapter.

I n d u s t r i a l BASIC f u n c t i o n s are

discussed

this

Function

waning

S I N (X)

S i n e of X ( X i s expressed i n r a d i a n s )

cos ( X )

Cosine of X ( X i s expressed i n r a d i a n s )

ATN ( X I

Arctangent of X ( r e s u l t expressed i n r a d i a n s )

EXP (XI

ex (e = 2.718282)

LOG(X)

N a t u r a l l o g of X (logex)

RND(X)

Random number

ABS ( X )

Absolute v a l u e of

INT (XI

I n t e g e r value of X

SGN ( X I

Sign of X
positive,
negative

SQR (XI

Square root of

FNA ( X )

User-def ined f u n c t i o n

TRC ( X )

Trace f u n c t i o n
Used f o r
I n d u s t r i a l BASIC programs.

x (1x1)

-0a s si ifg n Xa vi sa l u ez e r oof, +1
i f X is
o r -1 i f X is
x (fl)

debugging

OS/8

I n a d d i t i o n , t h e r e are a number of other f u n c t i o n s provided by OS/8
I n d u s t r i a l BASIC, which i n c l u d e p r i n t i n g f u n c t i o n s , s t r i n g h a n d l i n g
f u n c t i o n s , and UDC f u n c t i o n s . These f u n c t i o n s are d e s c r i b e d i n o t h e r
p a r t s of t h i s manual as i n d i c a t e d below.
PRINTING FUNCTIONS

Refer t o Paragraph

PNT ( X )

3.5.4

TAB (XI

3.5.3

6-1

7.2.1
7.2.2
7.2.2
7.2.3

7.2.3
7.2.4
7.2.5
7.2.6
REAL TIME FUNCTIONS

8.3.2

A N I (X,Y)

8.3.3
8.3.4
8.3.5
8.3.6
8.3.7
8.3.8
8.3.1
8.4.1
8.4.2
8.4.3

6.2

6.2.1

ARITHMETIC FUNCTIONS
The Random Number Function

- RND(XI

The RND(X) f u n c t i o n produces pseudo-random

numbers between

and

write

the

The argument X i s a dummy argument and can be any number.
If t h e u s e r wants t h e f i r s t 20 random numbers,
he
program shown below and get 2 0 s i x - d i g i t decimals.
READY
10 FOR L-1 TO 20
20 P R I N T F N D < X ) r
30 NEXT L
40 END

6-2

can

RU"H
0.361 572
0.53979 5
0.125244
0.440186

0.3327 64
0.8 479
B* 389 404
0 9 7 09 47

0.633057
0.026123
0.9 748 53
0.28 5889

0.350342
0054126
0.51 6357
0.867432

0. 6701 66
0.934326
0.465088
0. 178467

READY

A second RUN g i v e s e x a c t l y t h e same sequence of numbers as
RUN; t h i s i s done t o f a c i l i t a t e t h e debugging of programs.
RWNH
0.361 572
0.53979 5
0.125244
0.44018 6

0.3327 64
0.8479
0.389 404
0 9 7 09 47

0.633057
0.026123
0.974853
0.28 5889

the

0.350342
0.54126
0.51 6357
0.8 67432

first

0. 6701 66
0.9 3 4 3 2 6
0.465088
0.178467

READY

If t h e u s e r wants 20 random o n e - d i g i t i n t e g e r s , h e can change l i n e

t o read as follows:
20 P R I N T l N T C 10*RND<X))s
RWNH

The r e s u l t s w i l l be as follows:
3
8
3
9

3
5
1
4

6
0
9
2

4
1

To v a r y t h e type of random numbers ( 2 0 random numbers r a n g i n g
t o 9, i n c l u s i v e ) , t h e u s e r can change l i n e 20 as f o l l o w s :
20

PRINT INT (9*RND (X)+1);

To o b t a i n random numbers which are i n t e g e r s from 5 t o
t h e u s e r can change l i n e 20 t o t h e f o l l o w i n g :
20

from

24,

inclusive,

PRINT INT(20*FND(X)+5) ;

If random numbers are t o be chosen from the A i n t e g e r s o f which
the smallest, the u s e r can c a l l for INT.(A*RND(X)+B)

6-3

6.2.1.1

The RANDOMIZE Statement

t h e same numbers i n
t h e same o r d e r r e s u l t e d both t i m e s t h e program w a s run.
However, a
d i f f e r e n t set w i l l be produced w i t h t h e RANDOMIZE s t a t e m e n t , as i n t h e
f o l l o w i n g program:
As n o t e d i n t h e f i r s t program i n paragraph 6.2.1,

5 RANDOMIZE
10 FOR L= 1 TO 20
20 PRINT I N T < 10*RNDCX) 1;
30 NEXT L
4 0 END
READY
RU"H
3 3
READY
RUNNH
0 1
READY

RANDOMIZE resets t h e numbers based on e l a p s e d t i m e s p e n t w a i t i n g f o r
t e r m i n a l I/O.
For example, i f RANDOMIZE a p p e a r s a f t e r a P R I N T or
INPUT i n s t r u c t i o n b u t b e f o r e a s t a t e m e n t w i t h t h e RND(X)
function,
I f the
t h e n r e p e a t e d RUNS o f t h e program produce d i f f e r e n t r e s u l t s .
i n s t r u c t i o n i s a b s e n t , t h e o f f i c i a l l i s t o f random numbers i s o b t a i n e d
i n the u s u a l order. It i s suggested t h a t a s i m u l a t e d model should be
debugged w i t h o u t t h i s i n s t r u c t i o n so t h a t one always o b t a i n s t h e same
random numbers i n t e s t runs.
A f t e r t h e program i s debugged, and
b e f o r e s t a r t i n g p r o d u c t i o n runs, t h e u s e r i n s e r t s t h e following:
( l i n e number) RANDOMIZE
a t t h e a p p r o p r i a t e place i n t h e program.

6.2.2

The Sign Function

- SGN(X)

The SGN f u n c t i o n i s one which a s s i g n s t h e v a l u e 1 i f t h e argument i s
any p o s i t i v e number, 0 i f z e r o , and -1 if any n e g a t i v e number.
Thus,
SGN(7.23) = 1, S G N ( 0 ) = 0, and SGN(-.2387) = -1.
For example, the
following statement :
25

LET X=SQR(At2+2*B*C)*SGN(A)

a s s i g n s t h e s q u a r e root of t h e s i n e of A t o X.

6-4

6.2.3

The I n t e g e r Function

- INT(X)

The i n t e g e r f u n c t i o n r e t u r n s t h e v a l u e of t h e nearest i n t e g e r
not
X.
For example, INT(34.67) = 34.
By s p e c i f y i n g
greater
than
INT(X+.5) t h e INT f u n c t i o n can be used t o round numbers t o t h e n e a r e s t
INT can a l s o be used t o round
i n t e g e r : t h u s , INT(34.67+.5) = 35.
numbers t o any given decimal p l a c e by s p e c i f y i n g :
INT ( X * l O t D+ .5) /10 t D

where D i s t h e number o f
program i l l u s t r a t e s t h i s
t y p i n g a CTRL/C:

decimal p l a c e s d e s i r e d .
f u n c t i o n ; e x e c u t i o n has

The f o l l o w i n g
been stopped by

10 REM
I N T FUNCTICN EXAMPLE
20 P R I N T ssNUMBER T O BE R O l h V D E D s s ~
30 I N P U T A
40 P R I N T "NO.
O F DECIMAL PLACES:"s
50 I N P U T D
60 LET B = I N T C A * l 0 t D + . S ) / l 0 t D
7 0 P R I N T "A R O U N D E D =";B
80 G O T O 20
9 0 END
READY
RUNNH
NUMBER TO B E R O U N D E D ? 5 5 . 6 5 3 4 2
NO. O F D E C I M A L P L A C E S : ? 2
A ROUNDED = 55.65
NUMBER T O B E R O U N D E D ? I S . 375
NO. OF D E C I M A L P L A C E S : ? - 2
A ROUNDED = 100
NUMBER T O B E R O U N D E D ? 6 7 . 8 9
NO. O F D E C I M A L P L A C E S : ?- 1
A ROUNDED = 70
NUMBER TO BE R O U N D E D ? t C
READY

If t h e argument i s a n e g a t i v e number,
t h e value returned is t h e
l a r g e s t n e g a t i v e i n t e g e r (rounded t o t h e h i g h e r v a l u e ) c o n t a i n e d i n
t h e number.
For example, INT(-23) = -23 b u t INT(-14.39) = -15.

6.2.4

The Absolute Value Function

- ABS(X1

The a b s o l u t e value f u n c t i o n i s used t o o b t a i n t h e a b s o l u t e
v a l u e of an expression.
For example:
READY
5 PRINT ABS<-66)
10 END
RWNH

6- 5

(positive)

6.2.5

The Square R o o t Function

SQR(X)

The s q u a r e root f u n c t i o n is used t o compute
expression.
For example:

the

square

root

value

5 LET B=4\A=2* 5\C=. 5
1 0 P R I N T SQR<B* 2- 4* A* C)
20 END
RWNH
3.31 662
READY

If t h e argument of the SQR(X) f u n c t i o n is < O , t h e
t h e argument i s used,

6.3
6.3.1

absolute

TRANSCENDENTAL FUNCTIONS

The Sine Function

- SIN(X)

The s i n e f u n c t i o n is used t o c a l c u l a t e t h e s i n e of an a n g l e
i n radians. For example:

specified

5 REM
CALCULATE S I N E 30 DEGREES
1 0 LET P = 3 * 1 4 1 5 9
20 P R I N T S I N < 3 0 * P / 1 8 0 )
25 END
RWNH
0.5
READY

READY

6.3.2
The

The Cosine Function
cosine function

specified i n radians,

COS(X)

is used t o c a l c u l a t e

the

c o s i n e of

F o r example:

5 REM
CALCULATE THE C O S I N E OF 45 DEGREES
1 0 PRINT COS<45*3. 1 4 1 5 9 / 1 8 0 )
20 END
READY
RWNH
0.707108

6-6

angle

6.3.3

The A r c t a n Function

- ATN(X)

This f u n c t i o n calculates t h e angle ( i n r a d i a n s ) whose t a n g e n t is given
as t h e argument of t h e f u n c t i o n . For example:

READY
5 REM
CALCULATE ATNC.57735)
10 PRINT ATN(057735)
2 0 END
RUNNH
0.523598

6.3.4

The Exponential Function

- EXP(X)

The E X P ( X ) f u n c t i o n calculates t h e v a l u e of e r a i s e d t o t h e
For example:
where e i s e q u a l t o 2.71828.
5 REM

power,

CALCULATE EXPONWTIAL VALUE OF 1.5
10 PRINT EXP( 1.5)

20 END
READY
RWNH

4-48 168

6.3.5

The Natural Logarithm Function

The LOG(X) f u n c t i o n
example :

calculates

the

- LOG(X)
natural

5 REM
CALCULATE THE L O G OF 9 5 9
10 PRINT L O G ( 9 5 9 )
20 END
RUNNH

6.8 6589
READY

6-7

logarithm

For

6.4

USER DEFINED FUNCTIONS

6.4.1

The FNA(X) Function and t h e DEF Statement

I n a d d i t i o n t o t h e s t a n d a r d f u n c t i o n s OS/8 I n d u s t r i a l BASIC p r o v i d e s ,
t h e u s e r may d e f i n e up t o 26 f u n c t i o n s of h i s own w i t h t h e DEF
statement.
The name of t h e d e f i n e d f u n c t i o n must be t h r e e l e t t e r s ,
the f i r s t two of which are F N , i.e., FNA, FNB,...,FNZ.
Each DEF
s t a t e m e n t i n t r o d u c e s a s i n g l e f u n c t i o n and i s of t h e form:
( l i n e number) DEF FNA(X) =expression (X)
where A may be any l e t t e r and X is a dummy v a r i a b l e , b u t must be t h e
same on each side of t h e e q u a l s i g n . The DEF s t a t e m e n t may appear
anywhere i n t h e program so long as it a p p e a r s b e f o r e . t h e f i r s t use o f
t h e f u n c t i o n it d e f i n e s .
The f u n c t i o n i t s e l f can be d e f i n e d i n terms
of numbers, s e v e r a l variables, o t h e r f u n c t i o n s , or mathematical
exp e s s i o n s .
For example, i f t h e u s e r r e p e a t e d l y u s e s t h e f u n c t i o n

e-'

+5, h e can i n t r o d u c e t h e f u n c t i o n by t h e following:
30
DEF FNE ( X ) =EXP (-Xt2) +5

and c a l l f o r v a r i o u s v a l u e s of t h e f u n c t i o n by FNE( .1), FNE(3.45)
etc.
T h i s s t a t e m e n t s a v e s a great d e a l of t i m e when t h e
u s e r needs v a l u e s of t h e f u n c t i o n f o r a number o f d i f f e r e n t v a l u e s o f
the variable.

FNE(A+2),

The s t a t e m e n t :
DEF FNA(S) = S t 2

w i l l cause t h e later statement:
20

LET F+FNA(4)+1

t o be e v a l u a t e d as -17.
The user-defined
as shown below:
25

f u n c t i o n can be a f u n c t i o n o f more t h a n one v a r i a b l e ,

DEF FNL (X,Y ,2 ) =SQR(X a + Y t 2+Z+ 2 )

later s t a t e m e n t i n a program c o n t a i n i n g
appear as follows:

the

above

function

might

LET B=FNL(D,L,R)

where D , L, and R have been d e f i n e d i n t h e program.

6.4.2

The UDEF Function C a l l and t h e USE Statement

OS/8 I n d u s t r i a l BASIC h a s t h e c a p a b i l i t y f o r adding one or more
user-coded
assembly language f u n c t i o n s .
The u s e r f u n c t i o n s may u s e
f o u r numeric and t w o s t r i n g arguments, and once p r o p e r l y i n t e r f a c e d t o
OS/8
I n d u s t r i a l BASIC, t h e y can b e used as any o t h e r OS/8 I n d u s t r i a l
BASIC f u n c t i o n .
Complete i n s t r u c t i o n s f o r w r i t i n g and i n t e r f a c i n g

6-8

such f u n c t i o n s are provided i n Chapter 11 o f t h i s manual.
A
user-coded f u n c t i o n , i f p r e s e n t , i s s p e c i f i e d i n an OS/8 I n d u s t r i a l
BASIC program as:
( l i n e number) UDEF f u n c t i o n name (argument)

For example:
10

15
20

25
30
35
40

LET R=4
LET B=6
LET e 1 0
UDEF PLT(X,Y,Z)
LET DrPLT(R,B,O)
PRINT 4*D
END

Line 25 i n t r o d u c e s t h e f u n c t i o n PLT t o OS/8
I n d u s t r i a l BASIC and
i n d i c a t e s t h e number and t y p e of arguments a s s o c i a t e d w i t h t h e
function.
I n l i n e 30 t h e f u n c t i o n i s used as any o t h e r s t a n d a r d
I f the
f u n c t i o n might be used i n an OS/8 I n d u s t r i a l BASIC program.
f u n c t i o n r e q u i r e s t h e use of an a r r a y , a USE s t a t e m e n t i d e n t i f y i n g t h e
a r r a y must precede t h e s t a t e m e n t t h a t c a l l s t h e f u n c t i o n .

D I M S(15,5)

20
22

LET Q=10
USE S
UDEF PLT(X,Y,Z)

NOTE
A UDEF f u n c t i o n name

may c o n s i s t o f a l p h a b e t i c
characters
only and must have a t l e a s t one
argument ( a dummy argument i f n e c e s s a r y ) .

6.5

THE DEBUGGING FUNCTION

TRC(X)

The TRC(X) f u n c t i o n i s used by t h e programmer t o follow t h e p r o g r e s s
of a program and i s , t h e r e f o r e , a u s e f u l debugging aid. The form of
t h i s f u n c t i o n is:
( l i n e number) vl=TRC ( X )
where v l i s a dummy v a r i a b l e , X = l t u r n s t h e f u n c t i o n on and X=O t u r n s
the function off.
When T R C ( 1 ) i s encountered i n a program, OS/8
I n d u s t r i a l BASIC p r i n t s t h e l i n e number of each l i n e i n t h e program as
it is executed.
The l i n e numbers are p r i n t e d between a p a i r of
p e r c e n t s i g n s so as t o be d i s t i n g u i s h a b l e from o t h e r material t h a t i s
p r i n t e d by t h e program.
Program e x e c u t i o n t i m e i s slowed down
considerably t o accommodate the function and the e x t r a p r i n t i n g it
causes.
When TRC(0) i s encountered by t h e program t h e f u n c t i o n i s
turned o f f and normal program o p e r a t i o n resumes.

6-9

The f o l l o w i n g example shows t h e effect of using t h e TRC(X) f u n c t i o n i n
a program t o check the operation of a loop. The same program with t h e
TRC(X) f u n c t i o n removed from t h e program, i s also shown.

5 REM

BASIC
6 REM
FACTORIAL PROGRAM
10 FOR J=1 TO 5
20 GOSUB 60
30 NEXT J
40 STOP
60 L E T S=1
62 T=TRC< 1)
65 FOR K = l TO J
70 LET S=S*K
75 NEXT K
77 T = T R C < 0 )
80 PRINT JIS
8 5 RETURN
9 0 GiD

RUVNH
X 65 X
X 70 X
X 77 x
1

2
3
4
5

READY

X 65 X
X 70 X
% 70 X
X 70 X
x 77 x
6

READY

RU"H
1

1
X 65 X
X 70 %
X 70 X
x 77 x

X 65
X 70
X 70
X 70
X 70
2 77
4
X 65
X 70
X 70
X 70
X 70
X 70
X 77
5

5 HEM
BASIC
6 REM
FACTORIAL PROGRAM
10 FOR J = l T O 5
20 GOSU6 60
30 NEXT J
40 STOP
60 L E T S= 1
65 FOR K = l TO J
70 L E T S=S*K
7 5 NEXT K
88 PRINT JIS
8 5 RETURN
9 0 END

%
X
X
2

x
24
X
X
X
X
X
X
X

120

6-10

1
2
6
24
120

NOTE
OS/8 I n d u s t r i a l

BASIC idles on i n p u t
Therefore, a trace should
statements.
n o t be on when i n p u t i s requested.

6.6

SUBROUTINES

i s a p a r t of t h e program performing some o p e r a t i o n t h a t
i s r e q u i r e d a t more than one p o i n t i n t h e program. Subroutines are
g e n e r a l l y placed p h y s i c a l l y a t t h e end of a program, u s u a l l y b e f o r e
DATA s t a t e m e n t s , i f any, and always before t h e END statement.

A subroutine

6.6.1

GOSUB and RETURN

Two s t a t e m e n t s are used e x c l u s i v e l y i n OS/8 I n d u s t r i a l BASIC t o handle
s u b r o u t i n e ; t h e s e are t h e GOSUB and RETURN s t a t e m e n t s .
When a program encounters a GOSUB s t a t e m e n t o f t h e form:
( l i n e number) GOSUB x
where x r e p r e s e n t s t h e f i r s t l i n e number of
then t r a n s f e r s t o t h a t l i n e .
For example:

...

the

subroutine,

control

GOSUB 200

When program e x e c u t i o n reaches l i n e 5 0 , c o n t r o l t r a n s f e r s t o l i n e 200:
the s u b r o u t i n e i s processed u n t i l e x e c u t i o n e n c o u n t e r s a RETURN
s t a t e m e n t of the form:
( l i n e number) RETURN
which causes c o n t r o l t o r e t u r n t o t h e s t a t e m e n t following t h e GOSUB
statement.
Before t r a n s f e r r i n g t o t h e s u b r o u t i n e , OS/8 I n d u s t r i a l
BASIC i n t e r n a l l y r e c o r d s t h e n e x t s t a t e m e n t t o be processed a f t e r t h e
GOSUB statement: t h u s t h e RETURN s t a t e m e n t i s a s i g n a l t o t r a n s f e r
c o n t r o l t o t h i s statement.
I n t h i s way, no matter how many d i f f e r e n t
s u b r o u t i n e s are called, or how many times t h e y are used, OS/8
I n d u s t r i a l BASIC always knows where t o go next.
The f o l l o w i n g program demonstrates a s i m p l e s u b r o u t i n e :

1 REM
T H I S PROGRAW I L L U S T R A T E S GOSUB AND RETURV
10 DEF F N A C X ) = A B S C I N T C X ) )
20 I N P U T A I B ~ C
30 GOSUB 100
4 8 L E T A-FMACA)
50 L E T B=FNACB)
60 LET C-FNACC)

6-11

70 PRINT
8 0 GOSUB 1 0 0

9 0 STOP
1 0 0 REM
T H I S SUBROUTINE P R I N T S OUT THE S O L U T I O N S
1 1 0 REM
OF THE EQUATION A < X t 2 ) + B < X ) + C = 0
1 2 0 P R I N T "THE EQUATI ON I S'r A3 s s * X t 2 + * 1 rB; ***%+"3 C
1 3 0 L E T D=B*B-4*A*C
1 4 0 I F D<,0 THEN 1 7 0
1 5 0 P R I N T "ONLY ONE SOLUTION. *.X=";-B/<2*A)
1 6 0 RETUW
170 I F D c 0 THEN 200
1 8 0 P R I N T "TWO SOLUTI ONS. * X = ' * i
18 5 P R I N T (-B+SQR<D) 1 /( 2*A) ;"AND X= "3 ( 9- SQR< D) > / < 2 * A )
1 9 0 RETURN
200 P R I N T "IMAGINARY SOLUTI WS. . X = ( " i
205 P R I N T - B / < 2 * A ) 3 " r " i SBR<-D)/(2*A);")
AND ("3
I'
207 PRI N T -B/( 2 * A ) 3 " J "3 - S Q R ( -D) /( 2*A) 3 ''>
2 1 0 RETURrV
900 END

READY
RUNNH
?1,. 5,-0 5
THE EQUATION I S 1 * X ? 2 + 0.5 * X + - 0 . 5
TWO S O L U T I O N S . . * X = 0 . 5 AiiD X = - 1
THE EQUATIOV I S 1 * X t 2 + 0 *X+
IMAGINARY S O L U T I O N S * * * X = < 0 J

1
1 1 AND

< 0 J-1

)

Line 100 b e g i n s t h e s u b r o u t i n e .
There are s e v e r a l p l a c e s i n which
c o n t r o l may r e t u r n t o t h e main program, depending upon a c e r t a i n
condition being s a t i s f i e d .
The s u b r o u t i n e i s executed from l i n e 30
and a g a i n from l i n e 80. When c o n t r o l r e t u r n s t o l i n e 9 0 , t h e program
e n c o u n t e r s t h e STOP s t a t e m e n t and e x e c u t i o n i s terminated.
I t i s important t o remember t h a t s u b r o u t i n e s should g e n e r a l l y be k e p t
The l a s t s t a t e m e n t i n t h e main
d i s t i n c t from the main program.
program should be a STOP o r GOT0 s t a t e m e n t , and s u b r o u t i n e s are
normally placed f o l l o w i n g t h i s s t a t e m e n t ,

More t h a n one s u b r o u t i n e may be used i n a s i n g l e program i n which case
t h e s e can be p l a c e d one a f t e r a n o t h e r a t t h e end o f t h e program ( i n
l i n e number sequence). A u s e f u l p r a c t i c e i s t o a s s i g n d i s t i n c t i v e
For example, i f t h e main program i s
l i n e numbers t o s u b r o u t i n e s .
numbered w i t h l i n e numbers up t o 1998 200 and 300 could be used as t h e
f i r s t numbers of two s u b r o u t i n e s .
6.6.2

N e s t i n g Subroutines

N e s t i n g of s u b r o u t i n e s o c c u r s when one s u b r o u t i n e c a l l s a n o t h e r
subroutine.
I f a RETURN s t a t e m e n t i s encountered d u r i n g e x e c u t i o n of
a s u b r o u t i n e , c o n t r o l r e t u r n s t o t h e s t a t e m e n t f o l l o w i n g t h e GOSUB
which called it. From t h i s p o i n t , it i s possible t o t r a n s f e r t o t h e
b e g i n n i n g or any p a r t of a s u b r o u t i n e , even back t o t h e c a l l i n g

6-12

ubroutine.
Multiple
entry
b r o u t i n e s more v e r s a t i l e .

points

and

RETURN

statements

make

The m a x i m u m l e v e l of GOSUB n e s t i n g i s t e n l e v e l s , which should prove
more than adequate f o r a l l normal uses. Exceeding t h i s l i m i t r e s u l t s
i n t h e message:
GS AT LINE YYYYY

where YYYYY r e p r e s e n t s t h e l i n e number where t h e error occurred.
An
example of GOSUB n e s t i n g follows (execution has been stopped by t y p i n g
a CTRL/C, as the program would o t h e r w i s e c o n t i n u e i n an i n f i n i t e
loop)
0

10 REM
FACTORIAL P R O G R W U S I N G GOSUB T O
15 RE#
RECURSIVELY COMPUTE T 4 E S E FACTORS
40 I N P U T N
50 1 F N>20 THEN 120
60 X = l
70 K=l
80 GOSUB 200
9 0 P R I N T "FACTORI AL ";N; *'='*; X
110 GO T O 40
120 P R I N T "MUST BE 20 OR LESS"
130 GO T O 40
200 X = X * K
210 K = K + 1
220 I F K<=M THEN 200
230 RETURN
240 END

READY
RUNNH
?2
FACTORIAL

FACTORIAL

4 = 24

?S
FACTORIAL 5
120
?21
MUST BE 20 OR L E S S
?6
FACTORI AL 6 = 720
?f

READY

6-13

CHAPTER 7

ALPHANUMERIC INFORMATION (STRINGS)

I n p r e v i o u s c h a p t e r s w e have dealt o n l y w i t h numerical information.
OS/8 I n d u s t r i a l BASIC also p r o c e s s e s , o r manipulates,
However,
alphanumeric information called s t r i n g s . A s t r i n g i s a sequence of
characters, each of which i s a l e t t e r , a d i g i t , a space, or some
c h a r a c t e r o t h e r than a s t a t e m e n t t e r m i n a t o r ( b a c k s l a s h or c a r r i a g e
return)

7.1
7.1.1

STRING CONVENTIONS

Constants and Variables

S t r i n g s may appear as c o n s t a n t s or v a r i a b l e s j u s t as numerics may. we
have a l r e a d y used s t r i n g c o n s t a n t s i n PRINT s t a t e m e n t s .
For example:
100

PRINT "THIS IS A STRING CONSTANT"

where the alphanumerics enclosed i n q u o t e s are t h e s t r i n g c o n s t a n t .
It
Naming a s t r i n g v a r i a b l e is similar t o naming a numeric v a r i a b l e .
c o n s i s t s of a l e t t e r followed by a d o l l a r s i g n ($1 or a l e t t e r and a
s i n g l e d i g i t followed by $.
A$ and Al$ are b o t h l e g i t i m a t e s t r i n g
v a r i a b l e names; 2AS and AAS are n o t legitimate s t r i n g variable names.
7.1.2

Dimensioning S t r i n g s

OS/8 I n d u s t r i a l BASIC assumes t h a t a s t r i n g l e n g t h i s 8 c h a r a c t e r s
less u n l e s s a s t r i n g has been dimensioned i n t h e form:
10

D I M A$ (I)

where I is the l e n g t h of s t r i n g v a r i a b l e AS.

I cannot exceed 72.

S t r i n g lists ( e q u i v a l e n t t o s i n g l e s u b s c r i p t e d numeric v a r i a b l e s ) are
permitted i n OS/8
I n d u s t r i a l BASIC and must be dimensioned i n t h e
form:
20

D I M A$(K,L)

where K is t h e number of s t r i n g s i n t h e l i s t and L i s
each s t r i n g .

the

When r e f e r e n c i n g a s u b s c r i p t e d s t r i n g v a r i a b l e i n
s t a t e m e n t , f o r example :

LET

length

IF-THEN

LET B$(I) = "YES"

the e x p r e s s i o n I r e p r e s e n t s t h e place of t h a t s t r i n g v a r i a b l e
l i s t BS.

7-1

the

Double s u b s c r i p t e d s t r i n g v a r i a b l e s ( s t r i n g tables) are n o t
i n O S / 8 I n d u s t r i a l BASIC.
7.1.3

permitted

I n p u t t i n g S t r i n g Data

S t r i n g d a t a may be i n c l u d e d i n a DATA l i s t b u t must always be e n c l o s e d
by q u o t a t i o n marks.
I n f a c t , any s t r i n g w r i t t e n i n t o a program must
be e n c l o s e d by q u o t a t i o n marks t o be recognized by t h e OS/8 I n d u s t r i a l
BASIC Compiler.
10
20
25
30

FtEAD A$,B$,C$
PRINT C$;B$:A$
DATA "NG" " R I " ,"ST"
END

The program above p r i n t s STRING.
Quotation marks may be i n c l u d e d i n s t r i n g s by i n d i c a t i n g t w o q u o t a t i o n
marks i n succession.
For example t h e s t r i n g A"B would appear i n a
program as:
10

LET A$ = "A""B"

Both s t r i n g data and numeric data may be i n t e r m i x e d i n a DATA l i s t b u t
t h e burden f a l l s on t h e programmer t o assemble t h e l i s t i n t h e correct
sequence, s i n c e a l l READ s t a t e m e n t s f o r both s t r i n g and numeric data
remove d a t a s e r i a l l y from t h e DATA l i s t . I f h e does n o t , t h e r e s u l t s
of t h e READ s t a t e m e n t are u n p r e d i c t a b l e .
The INPUT s t a t e m e n t may a l s o be used f o r i n p u t t i n g s t r i n g data t o a
program.
Q u o t a t i o n marks are n o t n e c e s s a r y when i n p u t t i n g s t r i n g data
i n response t o t h e q u e s t i o n mark ( ? ) g e n e r a t e d by t h e I N P U T s t a t e m e n t
u n l e s s t h e q u o t a t i o n marks are d e l i b e r a t e l y meant t o be p a r t of the
string.

330
340
350
360
370
380
390
400
410

PRINT "DO YOU W I S H TO CONTINUE?"
INPUT A$
I F A$="YES" THEN 410
PRINT "ARE YOb SURE?"
INPUT B$
I F B$="NO" THEN 410
PRINT "PROGRAM STOPPED"
STOP
PRINT "LET'S CONTINUE"

.
.

490

END

Each s t r i n g l i t e r a l r e q u e s t e d by an INPUT s t a t e m e n t must be t e r m i n a t e d
by a c a r r i a g e r e t u r n or comma which acts as t h e data delimiter. T h i s
i s n e c e s s a r y s i n c e a l l c h a r a c t e r s , e x c e p t f o r t h e carriage r e t u r n o r
comma, are recognized as p a r t of t h e d a t a s t r i n g .

7-2

READY

...

I N P U T A$,B$,C$

RU"H

?ABCD
?EFGH
?IJ

I n t h e above example A$="ABCD", B$="EFGH" and C$="IF".

7.1.4

S t r i n g s i n LET and IF-THEN Statements

S t r i n g s may be used i n both LET and IF-THEN
s t a t e m e n t s as a l r e a d y
i n d i c a t e d by some of t h e previous examples. Any o f t h e r e l a t i o n a l
may be used i n an IF-THEN
o p e r a t o r s d e c r i b e d i n paragraph 2.3.3
s t a t e m e n t t o compare s t r i n g s .
S t r i n g s are compared on t h e b a s i s of
t h e A S C I I numeric value of each c h a r a c t e r i n t h e s t r i n g (see Appendix
D f o r numeric v a l u e s of A S C I I c h a r a c t e r s ) .
When comparing s t r i n g s i n an IF-THEN
statement,
operators have t h e following s i g n i f i c a n c e :

the

relational

Operator

Meaning

e a r l i e r i n A S C I I numeric order than

l a t e r i n A S C I I numeric order t h a n

=< 01: <=

same A S C I I numeric order
A S C I I numeric o r d e r t h a n

same A S C I I numeric order

earlier

>< or <>

d i f f e r e n t A S C I I numeric order from

=> 01: >=

same A S C I I numeric order as or l a t e r i n A S C I I
numeric order than

For example:
10

I F "ABCD"<"ABC@"
STOP

THEN 50

LET A$="ABCD"

Each c h a r a c t e r i n s t r i n g ABCD i s

compared, l e f t - t o - r i g h t ,
w i t h the
A, B, and C match b u t D and @ do
From Appendix D, t h e c h a r a c t e r @ h a s a lower numeric v a l u e t h a n

respective c h a r a c t e r i n s t r i n g AB@.

not.

7- 3

t h e character D.
Therefore t h e s t r i n g ABCD i s n o t e a r l i e r i n A S C I I
numeric sequence t h a n ABC@ and the program s t o p s a t l i n e 20.
I f t h e s t r i n g s i n an IF-THEN comparison are o f unequal l e n g t h , t h e n
I n d u s t r i a l BASIC l e n g t h e n s t h e shorter s t r i n g t o make it e q u a l i n
l e n g t h t o the l o n g e r s t r i n g by appending an a p p r o p r i a t e number o f
A S C I I space c h a r a c t e r s .
I n t h e f o l l o w i n g example
OS/8

10
20

I F "ABCD"6"AB"
STOP

LET A$="ABCD"

THEN 50

s t r i n g "AB" i s treated as "ABuu".
Since t h e c h a r a c t e r C
i n A S C I I numeric order t h a n t h e character "space",
s t a t e m e n t i s t r u e and c o n t r o l i s t r a n s f e r r e d t o l i n e 50.
7.1.5

i s earlier
t h e IF-THEN

S t r i n g Concatenation

S t r i n g s can be concatenated by means of t h e operator ampersand ( & ) .
The ampersand can be used t o c o n c a t e n a t e s t r i n g e x p r e s s i o n s wherever a
s t r i n g e x p r e s s i o n is legal, w i t h t h e e x c e p t i o n t h a t i n f o r m a t i o n cannot
be stored by means of a LET s t a t e m e n t i n concatenated s t r i n g
variables.
That i s , concatenated s t r i n g v a r i a b l e s cannot appear t o
t h e l e f t of the e q u a l s i g n i n a LET s t a t e m e n t .
For example, LET
A$=B$&C$ i s l e g a l , b u t U T A$&B$=C$ is not.
An example of s t r i n g
c o n c a t e n a t i o n is:
10
20

25
30

READ A$,B$,C$
PRINT C$&B$&A$
DATA "NG","RI","ST"
END

Running t h i s program (a m o d i f i c a t i o n
7.1.3) c a u s e s S T R I N G t o be p r i n t e d .

7 2

the

program

paragraph

STRING HANDLING FUNCTIONS

of f u n c t i o n s have been implemented t h a t perform manipulations
on s t r i n g s . These f u n c t i o n s are LEN, ASC, CHR$, VAL, STR$, Pas, SEG$,
and DAT$. Functions t h a t r e t u r n s t r i n g s have names t h a t end i n a
dollar s i g n ( $ 1 ; those f u n c t i o n s t h a t r e t u r n numbers have names t h a t
do n o t end i n a d o l l a r sign.

A number

7.2.1

The LEN Function

The LEN f u n c t i o n r e t u r n s t h e number of characters i n a s t r i n g .
t h e form:

7- 4

I t has

Example :
5 DIM B$( 10)
10 READ A B s B S
20 P R I N T LEN( A$&B$&"AROUND")
38 DATA "UPS DOWNS AND "
48 END
READY
RWNH

READY

7.2.2

The ASC and CHR$ Functions

The ASC and CHR$ f u n c t i o n s perform conversion from and t o A S C I I ,
respectively.
T h e ASC f u n c t i o n c o n v e r t s a one-character s t r i n g t o i t s
A S C I I decimal e q u i v a l e n t , and t h e CHR$ f u n c t i o n c o n v e r t s a decimal

number t o i t s e q u i v a l e n t A S C I I character.
The ASC f u n c t i o n has t h e form:
ASC (argument)

The argument i s a one c h a r a c t e r s t r i n g .

ASC

returns

the

equivalent

A S C I I decimal number for t h e character.
T h e CHR$ f u n c t i o n has t h e form:

CHR$ (numeric e x p r e s s i o n )
The value of t h e numeric e x p r e s s i o n i s t r u n c a t e d t o an i n t e g e r t h a t i s
i n the range 0 t o 63. I n t e g e r s greater t h a n 63 are treated modulo 6 4 .

That i s , they are d i v i d e d by 64 and t h e remainder- becomes t h e new
integer.
This i n t e g e r i s then i n t e r p r e t e d as an A S C I I decimal number
t h a t i s converted t o i t s e q u i v a l e n t c h a r a c t e r ( r e f e r t o Appendix D f o r
t h e A S C I I decimal numbers and t h e e q u i v a l e n t c h a r a c t e r s ) .
An example of t h e ASC and CHR$ f u n c t i o n s follows:

5 FOR T=ASC ("A") TO ASC ("A") +3
7 NEXTT
1 0 P R I N T "THIS I S TEST "&CHR$(T)

T h i s i s t h e beginning of a FOR loop t h a t s u c c e s s i v e l y p r i n t s :

THIS IS TEST A

.
THIS I S TEST B

T H I S I S TEST C
h

7-5

.
THIS IS TEST D

7.2

The VAL and STR$ Functions

The VAL and STR$ f u n c t i o n s perform conversions from s t r i n g s t o numbers
and numbers t o s t r i n g s . The form o f t h e VAL f u n c t i o n is:
VAL ( s t r i n g e x p r e s s i o n )

The s t r i n g e x p r e s s i o n must look l i k e any number which may be l e g a l l y
typed i n response t o an INPUT s t a t e m e n t . VAL r e t u r n s t h e a c t u a l
number t h a t the s t r i n g r e p r e s e n t s .
The VAL f u n c t i o n does n o t r e t u r n
the ASCII value of the number t h a t t h e s t r i n g r e p r e s e n t s , i t r e t u r n s
The 25
t h e number. For example, VAL ( “ 2 5 ” ) r e t u r n s t h e number 25.
t h a t i s t h e argument t o VAL i s a s t r i n g , t h e 25 t h a t VAL r e t u r n s i s a

number

Example :
READY

INPUT A$

PRINT VAL(A$) *2

100

END

...

RUNNH

?2 4 6 1 1 1
4.92222
READY

The STR$ f u n c t i o n r e t u r n s t h e s t r i n g r e p r e s e n t a t i o n (as a
i t s argument. The form o f STR$ is:

number)

STR$ (numeric e x p r e s s i o n )
The s t r i n q t h a t i s r e t u r n e d is i n t h e form i n which numbers are o u t p u t
i n BASIC;
For example, PRINT STRS(1.76111124) p r i n t s t h e s t r i n g
1.76111.
7.2.4

The POS Function

The PoS f u n c t i o n i s of t h e form:
POS(XS,Y$,Z)
The f u n c t i o n r e t u r n s t h e l o c a t i o n i n s t r i n g XS of t h e f i r s t o c c u r r e n c e
of s t r i n g Y$ s t a r t i n g w i t h Zth c h a r a c t e r i n s t r i n g X$. For example:

7-6

20
25

LET X$="MONDAY"
LET X=POS (X$ ,"DAY" ,1)

A f t e r l i n e 25, X w i l l be e q u a l t o 4 .
The arguments
f u n c t i o n may be c o n s t a n t s , variables, o r expressions.

the

POS

The following r u l e s apply i n e v a l u a t i n g t h e POS(X$,Y$,Z) f u n c t i o n .
1.

I f Y$ i s a n u l l s t r i n g (no c h a r a c t e r s ) then
POS(X$,Y$,Z)=l

I f X$ i s a n u l l s t r i n g (no c h a r a c t e r s ) t h e n
POS ( X$ ,Y $ ,2) =o

I f Z < O , a f a t a l error (PA) i s d e t e c t e d and program
e x e c u t i o n stops
I f Y$ is n o t found, then

POS (XS ,Y$ 2) =o

THE SEG$ Function

7.2.5

This f u n c t i o n i s o f t h e form:
SEG$(X$,Y,Z)
The f u n c t i o n r e t u r n s t h e s u b s t r i n g o f X$ which i s between p o s i t i o n s
and 2 i n c l u s i v e l y .
For example:
20
25
30

LET X$="MONDAY"
LET B=6
LET A$=SEG$ (X$ ,2*B/3 , B )

A f t e r l i n e 30, A$ i s e q u a l t o "DAY".
The arguments
f u n c t i o n may be variables, c o n s t a n t s , or expressions.

the

SEG$

The following r u l e s apply i n e v a l u a t i n g t h e SEG$(X$,Y,Z) f u n c t i o n .

7.2.6

I f Y < O , Y is set e q u a l t o 1

I f Y> l e n g t h
characters)

I f Z,O,

I f 2 > l e n g t h X$, then 2 i s set e q u a l t o l e n g t h o f X$

I f Z,Y,

X$,

then

SEG$(X$,Y,Z) = n u l l

string

then SEG$(X$,Y,Z)= n u l l s t r i n g

t h e n SEG$(X$,Y,Z) = n u l l s t r i n g

The DAT$ Function

The DAT$ f u n c t i o n is o f t h e form:
DAT$ ( X I

7-7

(no

The f u n c t i o n r e t u r n s an e i g h t c h a r a c t e r s t r i n g g i v i n g the c u r r e n t date
i n t h e form MM/DD/YY,
For example:
SCRATCH

READY
20

PRINT DATS(X)
END

RU”H

7/ 1/73

The use of DAT$ f u n c t i o n assumes the u s e r has specified t h e date i n
monitor command “DATE”.
I f t h e DATE command w a s n o t used,
t h e OS/8

the DAT$ f u n c t i o n o u t p u t s a n u l l s t r i n g (no c h a r a c t e r s ) .
If t h e I n d u s t r i a l BASIC clock i s s e t , and t h e n exceeds One day, t h e
n e x t c a l l to t h e DAT$ f u n c t i o n w i l l r e t u r n t h e n e x t day and update t h e
OS/8 date,

7- 8

CHAPTER 8

REAL TIME OPERATIONS

8.1

GENERAL DESCRIPTION

This c h a p t e r c o n t a i n s t h e s t a t e m e n t s and f u n c t i o n s which g i v e t h e u s e r
t h e f a c i l i t y t o s u p p o r t asynchronous o p e r a t i o n , and c o n t r o l and
monitor e x t e r n a l devices.
The following BASIC Statements are used t o
with e x t e r n a l events :

TIMER
COUNTER
CONTACT
DISMISS

associate

BASIC

routines

-t i m ecbased
oper a t i o n s
ounter operations

-UDC
-UDC c o n t a c t o p e r a t i o n s

-termination of s e r v i c e routines

These s t a t e m e n t s are e x p l a i n e d i n d e t a i l l a t e r i n t h i s c h a p t e r .
The following f u n c t i o n c a l l s are used t o access,

synchronously,

Real

Time d e v i c e s :
AN0

-Analog I n p u t
-Analog Output

RDI
RDO

-Read d i g i t a l i n p u t
-Read d i g i t a l o u t p u t

SDO

-Send d i g i t a l o u t p u t
-Set counter
-Read c o u n t e r
-Set or read clock
-Information r e g a r d i n g
asynchronous o p e r a t i o n s

ANI

CN1
CNO
CLK
CNT
LNE
STA

These f u n c t i o n c a l l s are
chapter

8.2
8.2.1

also

explained

detail

later

this

REAL TIME BASIC STATEMENTS
TIMER
TIMER V THEN X

where X i s the l i n e number of t h e f i r s t s t a t e m e n t of the U s e r Process
I n t e r r u p t Service Routine ( U P I R ) , and V i s t h e t i m e i n t e r v a l i n
seconds.
When the t i m e i n t e r v a l has e l a p s e d the u s e r service r o u t i n e i s
scheduled for e x e c u t i o n and t h e t i m e r i s restarted. Time i n t e r v a l s of
less than .1 second may have s i g n i f i c a n t i n a c c u r a c i e s i n timing. Time
i n t e r v a l s which are z e r o o r n e g a t i v e d e a c t i v a t e a l l the t i m e r s
associated w i t h the specified l i n e number.
This a l l o w s the user t o
change t h e elapsed t i m e i n t e r v a l s o r s t o p t h e t i m e r s e n t i r e l y . A
maximum of 4 timers may be a c t i v e a t any t i m e .

8-1

Examples of TIMER S t a t e m e n t s :
200 TIMER 10 THEN 400
Every 1 0 seconds, t h e UPIR b e g i n n i n g a t l i n e 400 w i l l b e executed.
L)

300 TIMER 0 THEN 400
T h i s s t a t e m e n t w i l l cause a l l timers a s s o c i a t e d w i t h l i n e 4 0 0
U P I R t o be d e a c t i v a t e d .

the

1 0 0 TIMER 7 THEN 400
110 TIMER 3 THEN 400

These statements cause 2 t i m e r s t o start: a 7-second t i m e r t h a t w i l l
cause t h e U P I R a t l i n e 400 t o b e s c h e d u l e d f o r execution every 7
seconds, and a 3-second t i m e r t h a t w i l l cause t h e U P I R a t l i n e 400 t o
b e scheduled f o r e x e c u t i o n e v e r y 3 seconds. N o t e t h a t a t 21-second
i n t e r v a l s t h e U P I R w i l l b e scheduled t w i c e .
The f o l l o w i n g i s an example of a t i m e based o p e r a t i o n :
10

20
25
30
400
4 10
500
510
600

TIMER 1 0 THEN 400
TIMER 15 THEN 500
LET Y = 0
GOT0 25
PRINT "SEGMENT 400"

DISMISS
PRINT "SEGMENT 500"
DISMISS
END

t h i s example w i l l p r i n t "SEGMENT 400" e v e r y 1 0 seconds,
500" every 15 seconds u n t i l t e r m i n a t e d w i t h a CTRL/C.

8.2.2

and

"SEGMENT

COUNTER
COUNTER V THEN X

where X i s t h e l i n e number of t h e f i r s t s t a t e m e n t o f t h e U P I R and V i s
t h e c o u n t e r module t o a s s o c i a t e w i t h t h e given l i n e number.
There i s
a maximum of 4 c o u n t e r modules supported. As w i t h t i m e r s , when t h e
c o u n t e r number i s zero o r n e g a t i v e a l l c o u n t e r s a s s o c i a t e d w i t h t h e
l i n e number are d i s a b l e d .
Counter modules s h o u l d b e loaded v i a t h e

CNO f u n c t i o n f o r c o u n t i n g
a d d i t i o n a l information on Counter Modules refer t o
UNIVERSAL D I G I T A L CONTROL SUBSYSTEM MAINTENANCE MANUAL,

operations,

For

t h e UDC8
DEC-0 8-HZDC-D.

Example of a C o u n t e r Statement:

200 COUNTER 1 THEN 1000
When Counter 1 c o u n t s t o z e r o t h e U P I R a t l i n e 1 0 0 0 w i l l be scheduled.

8-2

The f o l l o w i n g i s an example of a program t o l o a d a c o u n t e r
number of i t e m s t o count and l o g t h e completion of t h e count:

10
20
25
30
35
100

8.2.3

with

COUNTER 1 THEN 100
REM NOW LOAD COUNTER
LET A = CN0(1,100)

LETA-0
GOT0 30
PRINT "COUNT CYCLE COMPLETE"

110

DISMISS

200

END

CONTACT

CONTACT V THEN X

where X is t h e l i n e number a s s o c i a t e d w i t h t h e s p e c i f i e d CONTACT.
The
value V i s t h e CONTACT number. The maximum number of CONTACTS i s 36,
i n t h e range 1 t o 36. I f zero is s p e c i f i e d as a CONTACT number a l l
active CONTACT u s e r i n t e r r u p t service r o u t i n e s a s s o c i a t e d w i t h t h e
l i n e number i n t h e CONTACT s t a t e m e n t are d e a c t i v a t e d .
Example of a CONTACT s t a t e m e n t :
200 CONTACT 1 THEN 600
300 CONTACT 2 THEN 600
400 CONTACT 3 THEN 700

A f t e r t h e s e statements are executed a change of s t a t e i n CONTACT 1 or
2 w i l l cause t h e U P I R a t l i n e 600 t o b e scheduled. A change of s t a t e
i n CONTACT 3 w i l l s c h e d u l e t h e U P I R a t l i n e 700.

8.2.4

DISMISS

terminate a u s e r i n t e r r u p t service
T h i s causes t h e m a i n l i n e code t o resume execution.
If
a n o t h e r u s e r p r o c e s s i n t e r r u p t r o u t i n e w a s s c h e d u l e d , it w i l l receive
control a t t h i s p o i n t . DISMISS performs an action s i m i l a r t o t h a t o f
RETURN.

A DISMISS s t a t e m e n t i s used t o

routine.

8.3

EXTENDED FUNCTIONS FOR INPUT OR OUTPUT

The Extended I/O Functions allow t h e user t o t u r n a d i g i t a l o u t p u t
"on" or " o f f " , r e a d a s w i t c h p o s i t i o n , set an a n a l o g v o l t a g e , or r e a d
a n a l o g voltage v i a t h e UDC.
An added f u n c t i o n allows r e a d i n g o r
s e t t i n g of t h e system clock.
Each class of f u n c t i o n a l I/O module
( a n a l o g i n p u t , analog o u t p u t ,
d i g i t a l i n p u t , d i g i t a l o u t p u t ) operates on a c o n t i n u o u s r a n g e of
logical addresses. The mapping between the logical address and the
c o r r e s p o n d i n g p h y s i c a l a d d r e s s of t h e UDC module and subchannel i s
performed w i t h i n t h e system, based on tables which d e f i n e t h e UDC
c o n f i g u r a t i o n and which t h e u s e r g e n e r a t e s d u r i n g "SYSTEM GENERATION".

8- 3

Thus, analog i n p u t p o i n t one (1) is d i f f e r e n t from a n a l o g o u t p u t p o i n t
(1).
This p r e v e n t s t h e u s e r from s p e c i f y i n g meaningless o p e r a t i o n s
( a t t e m p t i n g t o s e t a b i t "on" i n an i n p u t module).
I n a d d i t i o n , UDC
r e c o n f i g u r a t i o n s w i l l r e q u i r e o n l y a new table g e n e r a t i o n and no BASIC
l e v e l programming changes.
The logical a d d r e s s i n g s i m p l i f i e s t h e u s e
NEXT loops.
of FOR

I n g e n e r a l , a l l arguments t o t h e I n d u s t r i a l Functions must
t h e range:
0

argument

within

4095

Negative arguments w i l l g e n e r a t e a f a t a l error, FM; arguments t h a t are
o u t of range g e n e r a t e a FO.
8.3.1

The Clock Function

- CLK(X)

This f u n c t i o n h a s t w o o p e r a t i o n s :

I f X i s p o s i t i v e , t h e system c l o c k i s set t o t h e v a l u e o f X i n
seconds. The v a l u e of X must be less t h a n 86400 ( t h e number o f
seconds i n 24 h o u r s ) .

I f X i s z e r o o r n e g a t i v e , t h e v a l u e ( i n seconds) of t h e
clock is returned.

Example :
1.

S e t t h e system clock t o 12:OO:OO

100 LET T = 12*3600
200 LET X = CLK(T)
300 END
2.

Read the system clock

100 LET T = CLK(0)

Set t h e system clock t o the v a l u e e n t e r e d on t h e t e r m i n a l

50
75
100

GOT0 100

145
150

PRINT "INVALID TIME"
PRINT "ENTER PRESENT TIME AS HH:MM:SS";
INPUT A,B,C
I F A < 0 THEN 75
I F A > 23 THEN 75
IF B
0 THEN 75
IF B > 59 THEN 75
IF C < 0 THEN 75
I F C > 59 THEN 75
LET T = CLK(A*3600+B*60+C)

900

END

110

120
125
130
135
1 40

..
.

8-4

system

Analog I n p u t Function

8.3.2

- ANI(C,G)

This f u n c t i o n r e t u r n s t h e r e s u l t s , i n v o l t s , of reading channel (C) a t
gain
(G)
The
valid
gains
for
the
ADUOl
are :
1000,200,100,50,20,10,2,1.
Example :

Read analog i n p u t channel 6 a t a g a i n

volts

10,

input

voltage

100 LET V= ANI (6,101
200 PRINT V

t h e v a l u e p r i n t e d w i l l be 5.
8.3.3'

Analog Output Function

- ?NO(C,V)

The AN0 f u n c t i o n sets t h e analog o u t p u t channel (C) t o t h e v a l u e (V).
The a c t u a l o u t p u t generated is a f u n c t i o n of t h e modules used.
However, f u l l scale o u t p u t w i l l be generated by a v a l u e (V) of 1 0 2 3 ,
and minimum o u t p u t w i l l be generated by a value o f zero. Values
g r e a t e r than 1023 or less than z e r o are i l l e g a l .
Example of f u l l scale o u t p u t on channel 3:
100 LET A = AN0 (3,1023)

8.3.4

Read D i g i t a l I n p u t

- RDI (P,N)

This f u n c t i o n r e t u r n s t h e value of t h e d i g i t a l i n p u t p o i n t s s t a r t i n g
a t p o i n t P f o r N number of p o i n t s . The read may n o t cross a boundary
between modules ( p o i n t s d i v i s i b l e by twelve, i.e., 1 2 , 2 4 etc.)

Example :
100 LET A = RDI (25,4)
200 LET B = RDI (1,l)

Line 100 reads 4 p o i n t s (25-28) and r e t u r n s t h e v a l u e as A, t h i s is
u s e f u l f o r BCD i n p u t devices. Line 200 reads t h e value o f p o i n t 1 and
r e t u r n s a 1 i f t h e p o i n t i s "on", and a z e r o i f i t i s "off".
8.3.5

Send D i g i t a l Output

- SDO (P,N,V)

The SDO f u n c t i o n sets t h e d i g i t a l o u t p u t p o i n t ( s ) s p e c i f i e d by P and N
t o t h e value V.
The value must be a p o s i t i v e , and able t o be
r e p r e s e n t e d w i t h i n the range of N.
The d e f i n i t i o n of P and N i s t h e
same as i n t h e RDI function. The value of V, i n b i n a r y n o t a t i o n , i s
s e n t r i g h t - j u s t i f i e d i n t o t h e range s t a t e d .
Example :
100 LET A = SDO ( 4 , 1 , 1 )
200 LET A = SDO ( 1 , 4 , 1 0 )

8- 5

Line 1 0 0 w i l l t u r n p o i n t 4 on, w h i l e l i n e 200 w i l l t u r n
and 3.
8.3.6

Read D i g i t a l Output

points

- RDO (P,N)

T h i s f u n c t i o n i s i d e n t i c a l t o t h e R D I f u n c t i o n e x c e p t t h a t t h e "read"
i s of t h e d i g i t a l o u t p u t channel (s)
The data r e t u r n i s r e a d from a
table, n o t t h e a c t u a l p h y s i c a l channels.
T h e r e f o r e , o u t p u t modules
t h a t a l t e r s t a t e independently of computer o p e r a t i o n s ( s i n g l e s h o t
o u t p u t ) may be "on" i n the o u t p u t table b u t " o f f " p h y s i c a l l y .
8.3.7

Counter I n p u t

- CN1 (P)

This f u n c t i o n r e t u r n s t h e number of c o u n t s remaining
module.

the

counter

Example :
100 LET A = C N 1 (3)
A i s assigned t h e value of
counted i n c o u n t e r 3.

8.3.8

Counter Output

the

number

events

remaining

- CNO ( P , V )

Counter o u t p u t is used t o s e t a c o u n t e r module.
P i s t h e channel of
t h e c o u n t e r module, and V i s t h e v a l u e o f t h e number of i t e m s t o c o u n t
b e f o r e g e n e r a t i n g an i n t e r r u p t .
Example :
100 LET A = CNO (2,300)

T h i s w i l l set c o u n t e r 2 t o c o u n t 300 e v e n t s .

8.4

UPIR IDENTIFICATION FUNCTIONS

The f o l l o w i n g f u n c t i o n s p r o v i d e t h e u s e r w i t h a means o f i d e n t i f y i n g
t h e channel ( M E ) and s t a t e (STA) of t h e device t h a t caused t h e
interrupt.
T h i s w i l l a l l o w t h e u s e r t o have more t h a n one U P I R f o r
several modules of t h e same type.
8.4.1

Line

- LNE (XI

The LNE f u n c t i o n r e t u r n s t h e channel number o f t h e module t h a t
t h e i n t e r r u p t . The LNE f u n c t i o n h a s meaning o n l y i n a U P I R .

caused

Example :
1 0 0 LET A = LNE ( 0 )

Upon e n t r y t o t h e U P I R a t l i n e 100, A i s a s s i g n e d t h e
t h a t caused t h e U P I R t o be invoked.

8-6

channel

number

8.4.2

State

- STA (X)

The STA f u n c t i o n i s used t o f i n d t h e s t a t e of contact a s s o c i a t e d
t h e channel t h a t scheduled t h e U P I R .

with

Example :
1 0 0 LET A = STA (LNE (0))
A is a s s i g n e d t h e state o f t h e

that

changed

cause

the

T h i s f u n c t i o n r e t u r n s t h e number o f i d e n t i c a l
t h e same UPIR.

schedule

requests

for

contact

interrupt.
8.4.3

8.5

Count

- CNT (X)

EXAMPLE CONTROL PROGRAM

The example c o n t r o l program d e m o n s t r a t e s t h e m a i n t a i n i n g of a c o n s t a n t
t e m p e r a t u r e b a t h v i a t h e f o l l o w i n g operations:
1.

Open t h e h o t and c o l d water valves.

Open t h e d r a i n and t u r n t h e "BATH OK" lamp o f f .

Measure t h e b a t h t e m p e r a t u r e ; i f i t i s n o t 68 +or- .5 d e g r e e s
t u r n t h e "BATH OK" lamp o f f and a d j u s t t h e h o t water valve. I f
t h e b a t h t e m p e r a t u r e is 68 +or- .5 d e g r e e s t u r n t h e "BATH OK"
lamp on.

C l o s e t h e h o t and c o l d water valves, and open t h e
t h e s w i t c h i s c l o s e d t o s h u t down t h e p r o c e s s .

The hardware i n t e r f a c e s are as f o l l o w s :
ELEMENT

TYPE

POINT

HOT VALVE
COLD VALVE
DRAIN VALVE
BATH OK LAMP
TEMP. SENSOR
SHUT-DOWN SWITCH

UDC/DAC
UDC/DAC
UDC/DO
UDC/DO
UDC/ADUO 1
UDC/CI

1
2
1
3
4
2

The I n d u s t r i a l BASIC program would be:
100 R E M CONTACT 2 SHUTS DOWN ENTIRE RUN
120 CONTACT 2 THEN 960
140 REM SCAN FOR TEMPERATURE EVERY 5 SECONDS
160 TIMER 5 THEN 500
180 REM SET SOFTWARE SWITCH FOR RESTART
200 LET S-1
220 REM OPEN DRAIN VALVE
240 LET A=SDO(1,1,1)
260 REM OPEN HOT AND COLD VALVES 50%

8-7

drain

when

280
300
320
340
360
380
400
420
440
460
480
500
520
540
560

580

LET H-1023". 5 0
LET C=1023*. 5 0
LET A=ANO ( 1,H)
LET A=AN0(2 ,C)
RF,M SHUT BATH OK LAMP O F F
LET A = S D O ( 3 , 1 , 0 )
REM NOW IDDLE
LET A=O
I F S=O GOTO 1 4 0
GOT0 4 2 0

REM
LET WAN1 ( 4 , 2 0 0 )
GOSUB 6 8 0
R E M CONVERTS VOLTS TO DEGREES TEMPERATURE
I F T > 6 8 . 5 THEN 7 4 0
I F T < 6 7 . 5 THEN 8 0 0
REM TEMPERATURE OR TURN BATH OK LAMP ON
LET B = S D 0 ( 3 , 1 , 1 )
DISMISS
REM
mM SUBROUTINE TO CONVERT VOLTS TO DEGREES
RETURN

600
620
640
660
680
700
7 2 0 RF,M
7 4 0 LET H=H*.95
7 6 0 LET C=C*1.05
7 8 0 GOTO 8 6 0
8 0 0 LET H=H*l.OS
8 2 0 LET C=C*.95
8 4 0 REM STEP VALVE AND TURN OFF BATH OK LAMP
8 6 0 LET B=ANO(l,H)
8 8 0 LET B=ANO( 2 ,C)
9 0 0 LET B = S D O ( 3 , 1 , 0 )
9 2 0 GOTO 6 4 0
9 4 0 REM
9 6 0 LET S=STA(LNE ( 0 ) )
98 0 IF S=O THEN 1 1 4 0
1 0 0 0 REM SHUT BATH DOWN
1020 LET B=ANO(l,O)
1 0 4 0 LET B=ANO(Z,O)
1 0 6 0 LET B = S D O ( 3 , 1 , 0 )
1 08 0 LET B = S D O ( 1 , 1 , 1 )
1100 REM NOW STOP TIMER
1120 TIMER 0 THEN 5 0 0
1 1 4 0 DISMISS
1 1 6 0 END
NOTE

T h e system w i l l resume c o n t r o l when t h e
SHUT-DOWN
SWITCH i s r e s t o r e d t o normal

position

8-8

8.6

POWER FAIL

- RESTART

I f a power f a i l u r e occurs a t Run-Time t h e system w i l l close any o y n
f i l e s and chain t o a BASIC f i l e (PWRUP.BA).
The u s e r may w r i t e h i s
awn restart o p e r a t i o n s .

NOTE

TD8/E f i l e operations r e q u i r e t h a t t h e
I n t e r r u p t System be "off".
Therefore,
power f a i l on TD8/E's
may
not
be
d e t e c t e d i f f i l e I / O i s i n progress.
Closing an open f i l e w i l l d e l e t e any
f i l e w i t h t h e same name and extension.

8-9

CHAPTER 9

E D I T I N G AND CONTROL COMMANDS

S e v e r a l commands f o r e d i t i n g OS/8 BASIC programs and f o r c o n t r o l l i n g
t h e i r execution enable t h e u s e r t o perform such o p e r a t i o n s as:

. erase

c h a r a c t e r s or l i n e s

. l i s t p a r t or a l l of a program

. save

programs on v a r i o u s s t o r a g e d e v i c e s , and

, c a l l program from s t o r a g e devices.
NOTE

See Chapter 1 0 f o r a d e s c r i p t i o n of OS/8
s t o r a g e devices and f i l e s .

9 1
9.1.1

CORRECTING PROGRAMS

E r a s i n g C h a r a c t e r s and Lines

Errors made while t y p i n g programs a t t h e t e r m i n a l are
easily
corrected.
Typing a SHIFT/O o r p r e s s i n g t h e RUBOUT key causes
d e l e t i o n of t h e l a s t c h a r a c t e r typed, and echoes back arrow (+) on t h e
terminal.
One c h a r a c t e r i s d e l e t e d each t i m e t h e key i s typed.
For
example :

20 DEN F44--F FNA(X,Y)=Xf2+3*Y

The u s e r t y p e s N i n s t e a d of F and immediately n o t i c e s h i s mistake.
He
p r e s s e s t h e RUBOUT key ( o r SHIFT/O) t h r e e t i m e s , which i s once f o r as
many c h a r a c t e r s i n c l u d i n g spaces t o be d e l e t e d .
H e makes t h e
c o r r e c t i o n and continues t y p i n g t h e l i n e .
The typed l i n e e n t e r s t h e
computer only when t h e RETURN key i s pressed.
20 DEF FNA (X,Y)=Xt2+3*Y

Sometimes it is easier t o d e l e t e a l i n e b e i n g typed and r e t y p e t h e
l i n e r a t h e r than attempt a c o r r e c t i o n u s i n g r u b o u t s , Typing CTRL/U o r
p r e s s i n g t h e ALTMODE key w i l l delete t h e l i n e c u r r e n t l y b e i n g worked
on and echoes DELETED and a c a r r i a g e r e t u r n - l i n e feed. U s e o f t h e
CTRL/U or ALTMODE command i s e q u i v a l e n t t o t y p i n g rubouts back t o t h e
beginning of t h e l i n e .
To d e l e t e a l i n e t h a t has a l r e a d y been e n t e r e d i n t o t h e computer t h e
u s e r simply t y p e s t h e l i n e number followed by a c a r r i a g e r e t u r n .
Both
t h e l i n e number and t h e l i n e are removed from h i s program.

9-1

The u s e r may change i n d i v i d u a l l i n e s by simply t y p i n g them i n again.
Whenever a l i n e i s entered, i t r e p l a c e s any e x i s t i n g l i n e which h a s
t h e same l i n e number.
New l i n e s may be i n s e r t e d anywhere i n t h e
program by g i v i n g them l i n e numbers which are between t w o o t h e r
e x i s t i n g l i n e numbers.
Using t h e s e e d i t i n g c a p a b i l i t i e s , t h e program
may be modified and re-run u n t i l it works p r o p e r l y .

9.1.2

The RESEQ Program

A f t e r t h e user h a s e x t e n s i v e l y modified h i s program, h e may f i n d t h a t
some p o r t i o n s o f t h e program have l i n e numbers spaced so c l o s e l y
t o g e t h e r t h a t t h e y do n o t p e r m i t any f u r t h e r a d d i t i o n o f statements
s h o u l d he wish t o do SO.
Renumbering t h e l i n e s i n t h e program so a s
t o p r o v i d e a p r a c t i c a l increment between l i n e numbers can
be
accomplished a u t o m a t i c a l l y by u s i n g t h e RESEQ program l i s t e d below.
The RESEQ program is saved as RESEQ.BA.
I t s h o u l d be n o t e d t h a t t h e
RESEQ program modifies t h e l i n e numbers i n a l l statements c o n t a i n i n g
them (such as GOSUB and IF-THEN s t a t e m e n t s ) t o a g r e e w i t h t h e new l i n e
numbers a s s i g n e d t o s t a t e m e n t s by t h e program.
L i n e l e n g t h s must n o t
exceed 72 c h a r a c t e r s .
990
1000
1 01 0
1020
1030

REM PROGRAM RESEQ
D I M L$ (72) rF$ (1),C$ (1),NS (16)
D I M L2$ (72)
D I M N ( 350)
LET F$=CHR$ (2 8)

1040

PRINT "FILE" ;
INPUT N$
PRINT "START, STEP" ;
INPUT S1,S
LET Sl=INT (ABS (Sl))
LET S=INT (ABS(S))

1050
1060
1070
1080
1090
1100
1110
1120
1130
1140
1150
1160
1170
1180
1190
1200
1 2 10
1220
1230
1240
1250
1260
1270
1280
1290
1300
1310
1320
1330

LET T=O

LET N2=0
FILE #l:N$
LET I=1
INPUT #l:L$
IFEND #1 THEN 1320
LET L=LEN (L$)
GOSUB 1980
I F N1>0 THEN 1220
PRINT "NO LINE NUMBER"
PRINT L$
GO TO 1130
I F N b N 2 THEN 1260
PRINT "OUT O F SEQUENCE"
PRINT L$
GO TO 1130
LET N2=N1
LET T=T+l
LET N ( T ) = N l
I F T<350 THEN 1130
PRINT "TOO MANY LINES"

STOP
RESTORE #1
FILEV #2:N$

9-2

1340
1350
1360
1370
13 80
1390
1400
1410
1420
1430
1440
1450
1460
1470
1480
1490
1500
1510
1520
1530
1540
1550
1560
1570
15 80
1590
1600
1610
1620
16 30
1640
1650
1660
1670
16 80
1690
1700
1710
1720
1730
1740
1750
1760
1770
1780
1790
1800
1810
1820
1830
1840
1850
1860
1870
1880
189 0
19 00
1910
1920

LET N2=S1
INPUT #1: L$
IFEND #1 THEN 1730
LET 1=1
LET L=LEN (L$)
GOSUB 1980
LET L2 $=STR$ (N2)
PRINT #2:L2$;
LET L$=SEG$(L$,I,72)
LET N2=N2+S
LET F=O
LET D=POS (L$,F$ ,l)\LET P=D
IF D = O THEN 1490
LET L2$=SEG$(L$,P+1,72)
LET L$=SEG$ (L$,1 ,P-l)
LET I=POS (L$,"GOTO" ,I)+4
IF I>4 THEN 1750
LET I=POS (L$,"GOTO" ,1)+5
IF I>5 THEN 1750
LET I=POS (L$,"THEN" ,1)+4
IF I>4 THEN 1750
LET I=POS (L$,"GOSUB", 1)+5
IF I>5 THEN 1750
LET I=POS (L$ "GOSUB" ,1)+6
IF I>6 THEN 1750
IF F=O THEN 1610
PRINT #2 :F$;
PRINT #2:L$;
LET F=F+l
IF D>O THEN 1660
PRINT #2:
GO TO 1350
LET D=POS(L2$,F$,l)\LET P=D
IF D>O THEN 1700
LET L$=L2$
GO TO 1490
LET L$=SEG$ (L2$,I , P - l )
LET L2 $=SEG$ (L2$ ,P+l, 72 )
GO TO 1490
CLOSE #2
STOP
LET -LEN (L$)
GOSUB 1920
IF C=32 THEN 1760
IF CtO THEN 1890
LET 1 ~ 1 - 1
LET P=I
GOSUB 1980
IF N1=0 THEN 1890
FOR J=1 TO T
IF Nl<>N(J) THEN 1880
LET Q$=sTR$(J*s-s+s~)
LET L$=sEG$(L$,~,P-~)LQs
GO TO 1590
NEXT J
PRINT "BAD REFERENCE"
PRINT L$
GO TO 1590
IF I<=L THEN 1950

9-3

1930
1940
1950
1960
1 9 70
1980
1990
2000
2010
2020
20 30
2040
2050
2060
2070

LET C=-1
RETURN
LET C=ASC(SEG$(L$,I,I))
LET I = I + l
RETURN
LET N1-0

GOSUB 1920
I F C<48 THEN 2040
I F 0 5 7 THEN 2040
LET Nl=N1*10+C-48
GO TO 1990
I F C<O THEN 2060
LET I=I-1
RETURN

END

T y p i c a l l y , t h e program would be used as follows:
SAVE SYS:SAMPLE

U s e r saves program SAMPLE which r e q u i r e s
renumbering.

READY

BASIC i s ready f o r next command.

OLD SYS:RESEQ

U s e r c a l l s f o r program RESEQ.

READY

BASIC i s ready for next command.

RU"H

U s e r r u n s program.

FILE? SYS:SAMPLE.BA

Program
responds

asks
with

for
name

filename.
o f program

User

t o be

renumbered.
START, STEP?lOO,lO

Program a s k s f o r a s t a r t i n g l i n e number
(START) and f o r t h e increment between
l i n e numbers (STEP)
User r e q u e s t e d
t h a t SAMPLE s t a r t w i t h l i n e number 100
and e a c h l i n e be incremented by 1 0 .

ReADY

Renumbering i s
accomplished.
r e a d y f o r n e x t command.

OLD SYS:SAMPLE

U s e r c a l l s back h i s program.

READY

BASIC ready for next command.

LISTNH

U s e r g e t s l i s t i n g o f program SAMPLE

f u r t h e r modification.
NOTE
A l l commands d e s c r i b e d i n t h e

following
paragraphs, e x c e p t LISTNH and RUNNH, may
two
be abbreviated u s i n g t h e f i r s t
letters o f t h e command.

9-4

BASIC

for

9.2

THE LIST AND LISTNH COMMANDS

An e n t i r e program can

b e l i s t e d on t h e t e r m i n a l by t y p i n g LIST
followed by a c a r r i a g e r e t u r n .
A heading i s p r i n t e d b e f o r e t h e
program i t s e l f and i s of t h e form:
FILE EX VERSION NO.

DATE

For example, i f t h e u s e r i s working on a
wants a l i s t i n g he t y p e s :

program

named

USER.BA

and

LIST

and BASIC responds w i t h :
USER

1.0

26- JUL- 72

100 LET X=l

.
..
.
b

200 END
READY
NOTE

When
any
OS/8
BASIC
command
is
completed, t h e message READY i s ‘ p r i n t e d
a t t h e terminal.
OS/8
BASIC i s t h e n
ready t o a c c e p t any o t h e r commands from
t h e user.
by a l i n e
number.
T h i s causes t h a t l i n e and a l l f o l l o w i n g l i n e s i n t h e program
t o be l i s t e d . For example:

A p a r t of a program may be l i s t e d by t y p i n g LIST followed

LIST 100

w i l l l i s t l i n e 100 and a l l remaining l i n e s i n t h e program.
Typing
CTRL/O w h i l e t h e l i s t i n g i s b e i n g p r i n t e d t e r m i n a t e s t h e p r i n t i n g and
o u t p u t s t h e READY message.
The LISTNH command may be used e x a c t l y as t h e
e l i m i n a t e s t h e heading from t h e l i s t i n g .

9.3

LIST

command,

but

THE SCRATCH COMMAND

The command:
SCRATCH

i s provided t o a l l o w t h e programmer t o clear h i s s t o r a g e area,
d e l e t i n g any commands, o r a program which may have been p r e v i o u s l y
9-5

e n t e r e d , and- l e a v i n g a c l e a n area i n which t o work.
If t h e s t o r a g e
area i s n o t cleared before e n t e r i n g a new program, l i n e s f r o m p r e v i o u s
programs may be executed a l o n g w i t h t h e new program, c a u s i n g errors o r
The SCRATCH command e l i m i n a t e s a l l o l d s t a t e m e n t s and
misinformation.
numbers and s h o u l d be used before new programs are created.

9.4

THE NEW COMMAND

The NEW command i s used t o name a program you are going t o create and
performs an i n h e r e n t SCRATCH on t h e storage area. The command i s i n
t h e form:

NEW FILE.EX
I t a s s i g n s t h e filename t o t h e program t o be created.

For example:

NEW USERA. BA

creates f i l e USERA.BA.
An a l t e r n a t e method of naming programs
RETURN key.
BASIC responds w i t h :

is t o t y p e NEW followed by

the

FILE NAME-The u s e r types t h e filename and e x t e n s i o n followed by t h e RETURN key.

NEW
FILE NAME--USER.BA

(.BA

i s assumed and need n o t

be t y p e d )
NOTE

Extension .BA i s assumed i n t h e OLD,
NEW, NAME, and SAVE commands u n l e s s
otherwise specified.
I f no e x t e n s i o n i s
specified
i n t h e OLD command, OS/8
I n d u s t r i a l BASIC first tries t o l o a d
FILE.BA
and i f u n s u c c e s s f u l tries t o
locate and load
FILE
without
the
extension.

9.5

THE OLD COMMAND

T h i s c o m a n d r e t r i e v e s a p r e v i o u s l y created f i l e from a storage device
and places the f i l e i n t h e s t o r a g e area of t h e computer. The command
is of the form:

OLD DEV:FILE.EX

9-6

For example:
OLD DTA1:SAMPLE.BA

r e t r i e v e s f i l e SAMPLE from DECtape number
s t o r a g e area of t h e computer.

1 and

places

An alternate method of r e t r i e v i n g a f i l e i s t o type
t h e RETURN key.
BASIC responds with:

OLD

the

followed

FILE ,NAME-The u s e r t y p e s t h e d e v i c e , filename
RETURN key.

and

extension

followed

the

storage

OLD

FILE NAME--DTAl:SAMPLE.BA
I f t h e d e v i c e i s o m i t t e d , DSK: i s assumed.

9.6

THE NAME COMMAND

T h i s command p e r m i t s t h e u s e r t o rename t h e program
area o f t h e computer. The command i s o f t h e form:

the

NAME FILE.EX

S i n c e t h i s command changes o n l y t h e name of t h e s t o r a g e area of t h e
n o t i t s c o n t e n t s , it can be used t o create t w o almost
computer
i d e n t i c a l v e r s i o n s of t h e same program.
T h i s i s accomplished by
r e t r i e v i n g the f i r s t f i l e , making m o d i f i c a t i o n s t o it, and t h e n
SAVEing (see paragraph 9.7) t h e modified version under t h e new name.

9-7

THE SAVE COMMAND

The SAVE command saves on t h e s p e c i f i e d d e v i c e t h e f i l e c u r r e n t l y
t h e s t o r a g e area o f t h e computer.
The command i s of t h e form:

SAVE DEV:FILE.EX

I f f i l e n a m e and e x t e n s i o n
I f d e v i c e i s o m i t t e d , DSK: i s assumed.
o m i t t e d , t h e c u r r e n t filename and e x t e n s i o n are used.

are

The SAVE command also p r o v i d e s a c o n v e n i e n t method f o r l i s t i n g l a r g e
programs q u i c k l y on t h e l i n e p r i n t e r r a t h e r t h a n t h e terminal.
For
example :
SAVE LPT:

l i s t s t h e c u r r e n t program on t h e l i n e p r i n t e r .

9-7

9.8

THE RUN AND R U " H

COMMANDS

A f t e r a I n d u s t r i a l BASIC program h a s been typed and i s i n core, it is
ready t o b e run.
T h i s i s accomplished by simply t y p i n g t h e command:
RUN
The

program heading i s p r i n t e d and t h e program b e g i n s e x e c u t i o n .
are encountered, a p p r o p r i a t e error messages a r e typed
on
t h e keyboard: o t h e r w i s e , t h e program r u n s t o completion, p r i n t i n g
When t h e END s t a t e m e n t i s reached,
whatever o u t p u t w a s requested.
OS/8 I n d u s t r i a l BASIC s t o p s e x e c u t i o n and p r i n t s :
If errors

READY

I f t h e program does n o t run p r o p e r l y , or c o n t a i n s an i n f i n i t e loop
and, hence, w i l l never s t o p , i t may b e t e r m i n a t e d by t y p i n g CTRL/C,
which r e t u r n s c o n t r o l t o the OS/8 I n d u s t r i a l BASIC e d i t o r (READY).
The RUNNH command s u p p r e s s e s p r i n t i n g of t h e heading and may
i n p l a c e of t h e RUN command.

used

NOTE

I f a program t h a t is n o t SAVEd i s RUN,
and f o r some reason i s n o t r e t r i e v a b l e
by LISTing, t h e program may be r e t r i e v e d
by c a l l i n g f o r OLD f i l e BASIC.WS.

9.9

THE BYE COMMAND

The BYE command i n s t r u c t s t h e computer t o e x i t from OS/8
Industrial
Typing a
BASIC and r e t u r n s c o n t r o l t o t h e OS/8 Keyboard Monitor.
CTRC/C w h i l e i n t h e OS/8 I n d u s t r i a l BASIC e d i t o r
(READY)
mode also
r e t u r n s c o n t r o l t o t h e OS/8 Keyboard Monitor.
NOTE

Never t y p e BYE b e f o r e SAVEing a newly
typed program.
Unless t h e SAVE command
i s used, t h e program w i l l be l o s t .

9-8

CHAPTER 1 0
FILES, FILE STATEMENTS AND C H A I N I N G

GENERAL INFORMATION ON OS/8 INDUSTRIAL BASIC FILES

10.1

Resident Devices

10.1.1

The f i l e c a p a b i l i t y provided by OS/8 I n d u s t r i a l BASIC allows t h e u s e r
t o w r i t e i n f o r m a t i o n i n t o (PRINT#) o r r e a d i n f o r m a t i o n from (INPUT#)
f i l e s . Only I / O t o d e v i c e s which are p a r t of t h e r e s i d e n t p o r t i o n of
t h e OS/8 Monitor may be done.
The Resident Device h a n d l e r i n c l u d e s
t h e devices:
SYS: and DTAl: f o r TD8E's

and
SYS: and RKBO: f o r RK8E's
A l l o t h e r c u r r e n t system d e v i c e h a n d l e r s c o n t a i n o n l y SYS:

10.1.2

F i l e Descriptions

F i l e s are r e f e r e n c e d s y m b o l i c a l l y by a name o f up t o s i x alphanumeric
c h a r a c t e r s followed, o p t i o n a l l y , by a p e r i o d and an e x t e n s i o n of t w o
alphanumeric c h a r a c t e r s .
The e x t e n s i o n t o a f i l e name i s g e n e r a l l y
used as an a i d f o r remembering t h e format o f a f i l e .
NOTE

files
operating
under
OS/8
Industrial
BASIC
are
considered
s e q u e n t i a l access f i l e s . That i s , t h e y
must be read o r w r i t t e n s e q u e n t i a l l y ,
another,
from
the
one i t e m a f t e r
beginning of t h e f i l e

All

10.1.2.1

Fixed Length F i l e s

A f i x e d l e n g t h f i l e i s one which i s a l r e a d y i n e x i s t e n c e .

That i s , i t

has been c r e a t e d and CLOSEd.
The l e n g t h of a f i x e d l e n g t h f i l e i s e q u a l t o t h e number o f b l o c k s
t h e f i l e and cannot be changed.
10.1.2.2

V a r i a b l e Length F i l e s

A variable l e n g t h f i l e i s a newly created f i l e .
Until the f i l e is
CLOSEd, it i s e q u a l i n l e n g t h t o t h e l a r g e s t f r e e space on t h e device.

When t h e f i l e i s CLOSEd it becomes a f i x e d l e n g t h f i l e e q u a l i n l e n g t h
t o t h e a c t u a l number of b l o c k s i t o c c u p i e s .

10-1

Unless t h e f i l e is CLOSEd, t h e CHAIN,
cause a loss of t h e f i l e .
10.1.2.3

STOP

END

statements

will

Numeric F i l e s

Data i n numeric f i l e s
are
stored
as
successive
three-word
floating-point
numbers (85 t o each OS/8 b l o c k ) with t h e l a s t word i n
each block unused.
10.1.3.4

ASCII F i l e s

Data i n ASCII f i l e s are s t o r e d i n s t a n d a r d OS/8 format ( t h r e e 8 - b i t
Refer t o Chapter 11 of t h i s manual
c h a r a c t e r s t o e v e r y t w o words).
and the O S / 8 Software Support Manual (DEC-S8-OSSMA-A-D).

10.2

FILE STATEMENTS

OS/8 I n d u s t r i a l BASIC p r o v i d e s a number o f s t a t e m e n t s f o r o p e r a t i n g on
files.
They i n c l u d e :
FILE#
PRINT#
INPUT#
RESTORE#
CLOSE #
I F END#
The s t a t e m e n t s are d i s t i n g u i s h a b l e from o t h e r OS/8 I n d u s t r i a l BASIC
s t a t e m e n t s by t h e number s i g n ( # ) which i s appended t o t h e statement.
10.2.1

The FILE# Statement

This statement is used t o open a f i l e and i s of t h e form:

( l i n e number) FILEtype numeric e x p r e s s i o n :
STRING EXPRESSION
where :
a.

FILEtype i s one of f o u r p o s s i b i l i t i e s :
FILE t y p e
FILE
FILEV
FILEN
FILEVN

Definition
Fixed l e n g t h

- A-S CASCII
II

- numeric
- numeric

V a r i a b l e length

Fixed l e n g t h

V a r i a b l e length

10-2

The numeric e x p r e s s i o n has a v a l u e of one o r t w o and r e p r e s e n t s
t h e i n t e r n a l f i l e number f o r t h e f i l e being .opened and
i s used i n any o t h e r s t a t e m e n t s r e f e r e n c i n g t h i s f i l e .

The s t r i n g e x p r e s s i o n i s e i t h e r a s t r i n g v a r i a b l e
c o n s t a n t which has a value o f t h e form:

or a string

DEV: F I L E EX

For example, t h e following program:
1 0 LET A$="DTAl :NETSAK. BA"
20 FILEN #l:A$

i s e q u i v a l e n t to:
1 0 FILEN #l:"DTAl:NETSAK.BA"

f o r opening f i x e d l e n g t h numeric f i l e NETSAK on DECtape number 1 and
a s s i g n i n g it i n t e r n a l f i l e number 1. I f DEV: i s missing from t h e
s t r i n g e x p r e s s i o n , t h e device DSK i s assumed by d e f a u l t .
NOTE

Only t w o f i l e s ,
(numbered 1 and 2 )
b e s i d e s t h e t e r m i n a l ( F I L E #0) may be
open i n a program a t any t i m e .
However,
t h e a b i l i t y t o open and close (CLOSE#)
f i l e s under program c o n t r o l p e r m i t s t h e
u s e r t o access an u n l i m i t e d number of
files.
When s e l e c t i n g a FILEtype, t h e u s e r should keep i n mind t h a t v a r i a b l e
l e n g t h f i l e s (FILEV and FILEVN) are restricted t o o u t p u t t i n g only.
That i s , v a r i a b l e l e n g t h f i l e s should be used i n c o n j u n c t i o n w i t h t h e
P R I N T # s t a t e m e n t only.
An attempt t o read ( I N P U T # ) from a v a r i a b l e
Only one FILEV or FILEVN may
l e n g t h f i l e r e s u l t s i n e r r o r message VR.
be active p e r device a t a given t i m e .
Fixed
l e n g t h ASCII f i l e s (FILE) should be r e s t r i c t e d t o
use
w i t h t h e INPUT# s t a t e m e n t , b u t may be used w i t h t h e PRINT# s t a t e m e n t
when t h e u s e r is c e r t a i n t h a t t h e A S C I I o r numeric d a t a h e i s P R I N T I N G
(i.e*, t h e number of c h a r a c t e r s ) r e p l a c e s , e x a c t l y , t h e A S C I I o r
numeric data on t h e f i l e .
I t is recommended t h a t t h e use o f f i x e d
l e n g t h A S C I I f i l e s (FILE) f o r o u t p u t be e n t i r e l y avoided.
10.2.2

The PRINT# Statement

The PRINT# s t a t e m e n t w r i t e s d a t a i n t o f i l e s and is of t h e form:

( l i n e number) PRINT #N:

l i s t of e x p r e s s i o n s and d e l i m i t e r s

where N i s t h e numerical e x p r e s s i o n f o r a f i l e number.
For A S C I I
f i l e s , t h e e x p r e s s i o n s i n t h e l i s t can be s t r i n g o r numeric, and t h e
TAB and PNT f u n c t i o n s can both be used.
The d e l i m i t e r s can be commas
or semicolons and have the same meanings that they have in t h e PRINT
s t a t e m e n t f o r t h e t e r m i n a l ( r e f e r t o Chapter 3 ) . For numeric f i l e s ,

10-3

the expressions
semicolons.

maybe

o n l y n u m e r i c v a r i a b l e s s e p a r a t e d by c o m m a s o r

1 0 FILEV # 1 : M B 0 :DATE. DA"
20 LET F = l
30 PRINT #F: TAB ( 2 8 ) ;DAT$ (X)
40 CLOSE #F
50 END

T h i s r o u t i n e p r i n t s t h e d a t e , s t a r t i n g a t column 28 on t h e d e v i c e RKBO
i n a f i l e named "DATE.DA"
10.2.3

The INPUT# Statement

The I N P U T # s t a t e m e n t r e a d s d a t a from f i l e s and i s of t h e form:
( l i n e number) I N P U T #N:

l i s t of v a r i a b l e s

where N i s t h e numerical e x p r e s s i o n f o r a f i l e number.
The INPUT#
s t a t e m e n t does not e x p e c t a l i n e number on each l i n e of d a t a i n t h e
file.
I f one i s p r e s e n t , it i s r e a d as d a t a :
1 0 D I M N$(19,15)
20 FILE #l:"LARRY"
30 FOR I=l TO 19
40 INPUT #1: N$(I)
50 NEXT I
60 END

The above r o u t i n e reads 19 s t r i n g s from f i l e LARRY.
NOTE

DSK: i s
example.

the

system

device

this

The p r e v i o u s paragraph i n d i c a t e d t h a t numbers may be w r i t t e n i n t o an
ASCII
file.
The r e a d i n g o f numbers from an ASCII f i l e r e q u i r e s some
p r e c a u t i o n i f t h e data d e l i m i t e r i s o t h e r t h a n a comma o r semicolon.
I n l i n e 30 of t h e example below, t h e data w r i t t e n i n t o f i l e number 1
w i l l b e s e p a r a t e d by a c a r r i a g e - r e t u r n and l i n e - f e e d which are b o t h
written i n t o the f i l e .
The subsequent r e a d i n g o f numbers from t h e
f i l e i n l i n e number 80 shows t h e u s e of a p a i r of dummy arguments ( C
and L) t o compensate f o r t h e c a r r i a g e - r e t u r n and l i n e - f e e d s i n c e t h e y
would o t h e r w i s e be read as numeric data w i t h a v a l u e o f 0.
10 FILEV #l:A$
20 FOR I = 1 TO 10
30 P R I N T #l:I
40 NEXT I
50 CLOSE #1
60 FILE #l:A$
70 FOR I = 1 TO 1 0
80 INPUT # 1 : J , C , L
90 NEXT I
100 END

10-4

10.2.4

The RESTORE# Statement

The RESTORE# s t a t e m e n t i s o f t h e form:
( l i n e n u d e r ) RESTORE #
where N is a numerical e x p r e s s i o n f o r t h e f i l e number t o be reset t o
t h e beginning.
I f N i s e q u a l t o zero, o r i f #N i s missing from t h e
s t a t e m e n t , t h e DATA l i s t i n t h e program i s reset t o t h e beginning.
10 FILE #2:"SUSAN"
20 INPUT #2: A,B,C,D
25 RESTORE #2
30 INPUT #2: E,F,G,H

This program u s e s t h e same values from system f i l e SUSAN f o r v a r i a b l e s
A, B, C , and D as it does f o r v a r i a b l e s E , F , G, and H.
10.2.5

The CLOSE# Statement

The CLOSE# s t a t e m e n t i s of t h e form:
( l i n e number) CLOSE #N
where N i s t h e numerical e x p r e s s i o n f o r t h e f i l e number t o be
For example:

closed.

10 D I M A$(5,10)
15 FOR 111 TO 4
20 LET A$ ( I ) = "SHERRY" & CHR$(I+48) &".BA"
25 FILE # l : A $ ( l )
30 INPUT # l : B $
35 I N B$="SANDY" THEN 60
40 CLOSE #1
45 NEXT I
50 PRINT "CANNOT FIND SANDY"
55 STOP
60 PRINT "FOUND SANDY I'

..
..
.
0

90 END

T h i s program s e a r c h e s through f o u r system f i l e s (SHERY1 through
SHERY4) f o r t h e f i l e t h a t has SANDY as t h e f i r s t e n t r y . I f t h e f i r s t
e n t r y i n the f i l e i s not SANDY, t h e f i l e i s c l o s e d ( s t a t e m e n t 40) and
t h e n e x t f i l e i s opened.
NOTE

The u s e r must CLOSE# a l l o u t p u t f i l e s
b e f o r e ending t h e program i n o r d e r t o
prevent t h e loss of d a t a .

10-5

10.2.6

The I F END# Statement

The I F END# s t a t e m e n t allows t h e u s e r t o determine whether o r
t h e r e has been an End-of-File d e t e c t e d f o r t h e f i l e i n q u e s t i o n .
s t a t e m e n t has t h e form:

not
The

( l i n e number) I F END #N THEN l i n e number
where N i s a numerical e x p r e s s i o n f o r t h e
number must refer t o a l i n e i n t h e program.

file

number.

last

INPUT#

The

line

..
0

...

106 I F END #1THEN 170

170 END
I f t h e IF END# s t a t e m e n t i s found t r u e ,
(read or w r i t e ) should be discarded.

the

PRINT#

The I F END# statement is n o t used t o determine i f more d a t a is
available, b u t r a t h e r t o determine i f t h e l a s t read or w r i t e was
valid.
The f i r s t a t t e m p t , i n an I N P U T # or PRINT# s t a t e m e n t , to read or w r i t e
p a s t an end-of-file
c a u s e s an abort o f t h e I / O associated w i t h t h a t
read or w r i t e , and t h e program p a s s e s c o n t r o l t o t h e n e x t o p e r a t i o n t o
be performed.
The second, and any subsequent a t t e m p t s , t o read or
w r i t e p a s t an e n d - o f - f i l e c a u s e s an RE o r WE
runtime error t o be
p r i n t e d f o r each s y n t a c t i c a l i t e m i n t h e I N P U T # or PRINT# list. To
avoid a l e n g t h y l i s t of error messages, avoid u s i n g long INPUT# or
PRINT# l i s t s i n s i t u a t i o n s which may approach an end-of-file.

10.3

THE CHAIN STATEMENT

The CHAIN s t a t e m e n t p r o v i d e s a convenient means f o r d i v i d i n g large
programs i n t o a series of smaller programs which are w r i t t e n and
stored s e p a r a t e l y , and e x e c u t e d i n a chain. The CHAIN s t a t e m e n t i s o f
t h e form:
( l i n e number) CHAIN "DEV:Filename.extension"
When BASIC e n c o u n t e r s a CHAIN s t a t e m e n t i n a program, it stops
execution of that program, retrieves the program named in t h e CHAIN

s t a t e m e n t from t h e s p e c i f i e d d e v i c e and f i l e , compiles t h e chained
The u s e of t h e CHAIN
program and b e g i n s e x e c u t i o n of t h e program.
s t a t e m e n t , t h e r e f o r e , i s t h e a u t o m a t i c e q u i v a l e n t of running an OLD
program w i t h no header (RUNNH).
The f i l e BASIC.WS w i l l c o n t a i n t h e
o r i g i n a l program i n t h e c h a i n and when e x e c u t i o n i s complete, t h e
BASIC s t o r a g e area w i l l c o n t a i n t h e o r i g i n a l program.

10-6

Since B A S I C removes t h e program which c o n t a i n s t h e CHAIN s t a t e m e n t
from core b e f o r e r e t r i e v i n g t h e chained program, t h e u s e r s h o u l d make
c e r t a i n t o CLOSE# a l l o u t p u t f i l e s t h a t are opened by F I L E s t a t e m e n t s
i n t h e program which c o n t a i n s t h e CHAIN s t a t e m e n t i n order t o avoid
t h e loss of d a t a generated by t h e program.
NOTES

1. Control commands OLD,
RUNNH,
are described i n Chapter 9.

and

SAVE

2 . I f DEV: i s n o t s p e c i f i e d ,
assumed by d e f a u l t .

DSK:

10-7

CHAPTER 11

CREATING ASSEMBLY LANGUAGE FUNCTIONS

11.1

INTRODUCTION

OS/8 I n d u s t r i a l BASIC has a f a c i l i t y which a l l o w s e x p e r i e n c e d PDP-8
assembly language programmers t o i n t e r f a c e t h e i r own assembly language
r o u t i n e s t o OS/8 I n d u s t r i a l BASIC. This f a c i l i t y p e r m i t s t h e u s e r t o
add f u n c t i o n s t o OS/8 I n d u s t r i a l BASIC which can o p e r a t e d i r e c t l y on
s p e c i a l purpose p e r i p h e r a l devices. T h i s c h a p t e r d e s c r i b e s i n some
d e t a i l t h e o r g a n i z a t i o n and i n t e r n a l c h a r a c t e r i s t i c s o f t h e OS/8
I n d u s t r i a l BASIC Run-time System (INBRTS) and i s i n t e n d e d t o serve as
a programming guide f o r t h e c r e a t i o n of such user-coded assembly
language f u n c t i o n s . T h i s material assumes t h e u s e r t o be f a m i l i a r
w i t h OS/8 and PDP-8 assembly language. For a d d i t i o n a l i n f o r m a t i o n on
e i t h e r subject, see t h e OS/8 SYSTEM REFERENCE MANUAL.
I n a d d i t i o n t o t h i s c h a p t e r t h e programmer would f i n d m o s t u s e f u l a
listing
of
the
OS/8
Industrial
BASIC
Runtime
System
(DEC-S8-LBASB-A-LA).

11.2

THE OS/8 INDUSTRIAL BASIC SYSTEM

The OS/8 I n d u s t r i a l
discrete p a r t s :
1.
2.

3.
4.

BASIC

system

divided

The BASIC e d i t o r
The BASIC compiler
The BASIC l o a d e r
The BASIC r u n t i m e system
The runtime system
over l a y s

into

the

following

(INBSI C SV)
( INBCMP SV)

(INBLDR. SV)
( INBRTS. SV)

(1NBSIC.AF)
(INBSIC. SF)
(INBSIC. FF)

The OS/8 I n d u s t r i a l BASIC e d i t o r i s used t o create and e d i t t h e source
program.
On r e c e i p t of a RUN command, t h e e d i t o r creates a temporary
f i l e c a l l e d BASIC.WS, stores t h e source i n t h a t f i l e , t h e n c h a i n s t o
t h e compiler.
The compiler compiles t h e program i n t o a 1 2 - b i t
pseudo-code which i s loaded i n t o c o r e a l o n g w i t h t h e runtime system by
t h e loader.
The run t i m e system i n t e r p r e t s each p s e u d o - i n s t r u c t i o n ,
On completion o f
c a l l i n g each o f t h e o v e r l a y s i n t o core as needed.
t h e program, t h e runtime system c h a i n s back t o t h e e d i t o r , and t h e
c y c l e i s repeated.
Following i s a diagram showing t h e f i l e s on t h e
systems d e v i c e a s s o c i a t e d with o r used by each system component.
BASIC Component

Associated
Files

Usage

BASIC. WS

program s t o r a g e

BASIC.WS
BASIC.TM

program s t o r a g e
compiled code s t o r a g e

11-1

compiled code storage

Loader

BASIC, TM

Rufime
System

INBS I C AF
1NBSIC.SF
INBS I C FF

.
.

overlays
( i f needed)

The u s e r must avoid u s i n g t h e filenames above: they are
t h e OS/8 I n d u s t r i a l BASIC System.

11.3

THE OS/8

reserved

for

INDUSTRIAL BASIC RUNTIME SYSTEM

A t t h e t i m e t h e u s e r ' s BASIC program i s a c t u a l l y b e i n g executed,
the
p o r t i o n o f t h e BASIC system i n c o n t r o l i s t h e Run t i m e System
(INBRTS)
INBRTS i s a l s o i n core when user-coded
f u n c t i o n s are

. and as such, a knowledge of it i s e s s e n t i a l t o w r i t i n g an

executed,

BASIC assembly language f u n c t i o n .
Note t h a t t h e f o l l o w i n g
s e c t i o n s r e f e r f r e q u e n t l y t o s p e c i f i c core l o c a t i o n s i n INBRTS by
The a c t u a l v a l u e of t h e s e
symbolic names (always c a p i t a l i z e d )
symbols can be o b t a i n e d from t h e symbol t a b l e (Appendix H) f o r t h e
Note t h a t t h i s symbol t a b l e i s f o r a
v e r s i o n of BASIC being used.
non-EAE system: t h e major r o u t i n e e n t r y p o i n t s mentioned i n t h i s
c h a p t e r , however, are t h e same f o r both systems. A l l diagrams i n t h i s
c h a p t e r have t h e lowest core a d d r e s s a t t h e bottom. This c h a p t e r a l s o
makes use of t h e v a r i a b l e names A, A ( 0 , O )
A$, and A$ ( 0 ) t o r e p r e s e n t
t h e g e n e r a l case. A l l r e f e r e n c e s i n t h i s c h a p t e r t o "page 0" r e f e r t o
t h e INBRTS page 0 (Page 0 , F i e l d 0 ) .
OS/8

11.3.1

INBRTS C o r e Layout

When e x e c u t i n g , INBRTS h a s t h e f o l l o w i n g c o n f i g u r a t i o n :
Resident

3S/8

FIELD N

Symbol

(where N=
h i g h e s t core
field in
machine )

Tables

N7400 OR N7600

In-core DATA
List

.
..
0

Array
Space

Pseudo Code
FIELD 1

11377

12400

F i l e Buffers

Process I / O
USR swap]

10000

(OS/8
%

11-2

07600

FIELD 0

F i l e Table

07577

Floating Point
Package

06677

INBRTS

04600

Interpreter

03400
0

The h i g h e s t core f i e l d i s used f o r INBRTS symbol t a b l e s , s t o r i n g o f
t h e f i e l d 1 and f i e l d 2 ( i f non-ROM TD8 /E) r e s i d e n t p o r t i o n s of t h e
OS/8 Monitor, t h e in-core DATA l i s t ( d a t a generated by DATA s t a t e m e n t s
i n t h e program) and pseudo-code
( g e n e r a t e d by t h e c o m p i l e r ) . The
bottom of t h e a r r a y space (marked by l i n e A) can exceed t h e f i e l d
boundary and proceed i n t o lower f i e l d s , b u t t h i s w i l l only happen f o r
Note t h a t i f t h e bottom of t h e pseudo-code e x t e n d s
l a r g e programs.
below l i n e B ( 1 2 4 0 0 ) , one f i l e b u f f e r space must b e s a c r i f i c e d , w i t h
corresponding loss of runtime f i l e c a p a b i l i t i e s .
A s t h e bottom of t h e
pseudo-code
approaches 12000, t h e number o f f i l e s which may be
simultaneously open a t runtime approaches 0. A t l e a s t 400(8) words of
b u f f e r must be f r e e f o r each f i l e opened a t runtime.
The f i l e b u f f e r s
a r e a l l o c a t e d dynamically a t runtime i n response t o FILE commands i n
t h e BASIC program, and i f n o t f u l l y used may be used as b u f f e r space
by t h e u s e r function.
11.3.2

INBRTS Overlays

Locations 3400-4577 o f f i e l d 0 s e r v e as an o v e r l a y area, i n t o which
t h e c u r r e n t l y needed o v e r l a y i s read. The o v e r l a y s c o n s i s t mainly of
f u n c t i o n s which are i n f r e q u e n t l y used, and are c o n s t r u c t e d as follows:
1NBSIC.AF

A r i t h m e t i c Functions

SIN, COS, ATN, EXP, FIX, FLOAT,
INT, RND, SGN, SQR, LOG
INBSIC. S R

S t r i n g Functions
CHR$, DAT$, LEN, POS, SEG$,
STR$, VAL, Error p r o c e s s i n g , TRC

ASC,

INBSIC. FF

F i l e Functions
CHAIN, CLOSE, FILE

Note t h a t t h e o v e r l a y d r i v e r r e a d s i n a new o v e r l a y o n l y i f t h e
o v e r l a y c u r r e n t l y r e s i d e n t does n o t c o n t a i n t h e f u n c t i o n s p e c i f i e d i n
a given f u n c t i o n c a l l .
I f t h e f u n c t i o n c a l l i s f o r a f u n c t i o n which
i-s found i n t h e c u r r e n t l y r e s i d e n t o v e r l a y , no o v e r l a y I / O t a k e s
place.
NOTE

On TD8E's i n t e r r u p t s are d i s a b l e d d u r i n g
t h e I / O f o r overlays.

11-3

11.3.3

INBRTS Symbol Tables

INBRTS locates v a r i a b l e s and s t r i n g s a t runtime v i a f o u r permanently
These tables, which always r e s i d e i n t h e
r e s i d e n t symbol tables.
h i g h e s t core f i e l d , are t h e S c a l a r Table ( f o r variables l i k e A, B l ) ,
t h e Scalar Array Table ( A ( 1 ) , B ( 1 , 1 ) )
t h e S t r i n g Symbol Table (AS,
Al$), and t h e S t r i n g Array Table, ( B l S ( 2 ) ) .
A more
detailed
d e s c r i p t i o n of t h e s t r u c t u r e of t h e s e tables can be found i n S e c t i o n
11.5.

11.4
11.4

DATA FORMATS

1 Variables

V a r i a b l e s are s t o r e d i n core as s t a n d a r d 3-word
numbers.
The f i r s t word i s a s i g n e d , 2's complement
t h e second and t h i r d words r e p r e s e n t t h e s i g n e d ,

floating point
exponent, w h i l e
2's complement

mantissa.

LOW MANTISSA

f HIGH MANTISSA

f exponent

S i n g l e v a r i a b l e s are stored as 3-word entries i n t h e S c a l a r Table.
Arrays
are s t o r e d i n core as successive 3-word entries, w i t h t h e
f i r s t s u b s c r i p t varying t h e f a s t e s t , and A(0,O) occupying t h e lowest
core address.
The a d d r e s s and f i e l d of A(0,O) are s p e c i f i e d i n t h e
S c a l a r Array Table.
The s t r u c t u r e of t h e symbol t a b l e s i s d e s c r i b e d
i n S e c t i o n 11.5.

A (M-2 , N )

11-4

Strings

11.4.2

S t r i n g s are s t o r e d as 6-bit A S C I I c h a r a c t e r s , w i t h a c h a r a c t e r c o u n t
as t h e f i r s t word of t h e s t r i n g . The l e f t h a l f of e a c h c h a r a c t e r word
i s used f i r s t , w i t h unused c h a r a c t e r s padded w i t h s p a c e s (40(8)). The
c h a r a c t e r c o u n t i s a s i g n e d , 2 ' s complement number r e p r e s e n t i n g t h e
a c t u a l number of c h a r a c t e r s i n t h e s t r i n g , n o t t h e number of words
devoted t o t h a t s t r i n g . Each s t r i n g i s a l l o c a t e d [INT(T)+l]
n+l
words,
where n i s t h e maximum l e n g t h s p e c i f i e d i n a
t h a t many words a r e a c t u a l l y used o r n o t .
BAS I C I t

DIM

statement,

whether

BRTS

count f o r
C
I'

count f o r
next s t r i n g

BA It

count __c

7773

"TS"
'I

7774

BR "

count

The minimum s t r i n g i s one c h a r a c t e r long. The a d d r e s s of t h e c o u n t
word f o r each s t r i n g i s p o i n t e d t o by i t s e n t r y i n t h e S t r i n g Symbol
Table.

S t r i n g a r r a y s are s t o r e d as s u c c e s s i v e s t r i n g s , w i t h A$(O) occupying
t h e lowest core address. Each s t r i n g i s a l l o c a t e d enough s p a c e f o r
i t s maximum l e n g t h , even though a l l of t h i s space may n o t be used.

I
I

1
I

count
n+l

I N T (-)

count

11-5

words where n i s t h e
maximum l e n g t h of
string specified i n
D I M statement

NOTE

For any of t h e above d a t a t y p e s , a f i e l d
boundary may f a l l anywhere w i t h i n any
Routines t h a t
use
individual i t e m .
s u c c e s s i v e words i n any data i t e m must
be c a r e f u l t o check f o r a f i e l d boundary
within t h a t i t e m .

In-core DATA l i s t

11.4.3

The in-core DATA l i s t i s stored as s e q u e n t i a l d a t a i t e m s i n core.
S t r i n g s again are devoted even numbers of words, and are p r e f i x e d by a
count. There i s no s e p a r a t o r or i d e n t i f i e r o f DATA i t e m s and t h e DATA
l i s t is always i n t h e h i g h e s t core f i e l d . A page 0 , f i e l d 0 p o i n t e r
t o t h e s t a r t i n g a d d r e s s of t h e DATA l i s t less 1 i s maintained a t
DLSTRT,
and t h e address of t h e l a s t word o f t h e l i s t can be found a t
DLSTOP

Example :
In BASIC:
DATA

1 I 2 , "THREE" I 4

In core:

FIELD N
'I

string
count 4

THREE

7773

2
FIELD fl

D h

STARTING ADDRESS
O F DATA L I S T

&------I

11-6

DLSTRT

word i n DATA l i s t
P o i n t e r t o DATA
l i s t -1

11.4.4

The S t r i n g Accumulator (SAC)

as one
The
of the o p e r a t i o n s , and t h e r e s u l t is always l e f t i n t h e SAC.
s t r i n g accumulator i s t o s t r i n g s as t h e hardware AC i s t o PDP-8
instructions.
The SAC s t a r t s a t location SAC f o r 36 words (72
c h a r a c t e r s ) , and t h e l e n g t h of t h e s t r i n g c u r r e n t l y i n t h e SAC i s
s t o r e d as a n e g a t i v e number i n STRLEN. A page 0 p o i n t e r t o t h e s t a r t
o f t h e SAC less 1 i s maintained a t SACPTR.
A l l INBRTS s t r i n g o p e r a t i o n s use t h e S t r i n g Accumulator (SAC)

11.5

INBRTS SYMBOL TABLE STRUCTURE

The INBRTS symbol tables all r e s i d e i n t h e h i g h e s t core f i e l d .
A CDF
t o t h e symbol table f i e l d can be found i n l o c a t i o n CDFIO of f i e l d 0.

11.5.1

The S c a l a r Table

The S c a l a r Table is t h e h i g h e s t symbol t a b l e i n c o r e , and i t c o n s i s t s
of successive
3-word entries, each e n t r y
c o n t a i n i n g a 3-word
f l o a t i n g - p o i n t number. One e n t r y e x i s t s f o r each v a r i a b l e used i n t h e
program, and a few e x t r a e n t r i e s are used as temporaries. A p o i n t e r
t o t h e s t a r t of t h e S c a l a r Table can be found a t l o c a t i o n SCSTRT of
f i e l d 0.
The scheme f o r s c a l a r v a r i a b l e s is as follows:
FIELD
X

Scalar
Table

F d F l

FIELD
0

CDFIO

CDF X

Variable
A

SCSTRT
SCALAR TABLE

11.5.2

The Array Symbol T a b l e

The Array Symbol Table c o n s i s t s of s u c c e s s i v e 4 - word e n t r i e s , each
e n t r y s p e c i f y i n g t h e l o c a t i o n and s i z e of an a r r a y used i n t h e
program. Each e n t r y i s as follows:
DIMENSION 2
DIMENSION 1

POINTER TO A ( 0 , O )

11-7

The first word o f each e n t r y i s a 1 2 - b i t p o i n t e r t o t h e l o c a t i o n o f
t h e exponent word of t h e f i r s t element i n t h e a r r a y .
The second word
i s a CDF N where N i s the f i e l d f o r t h e p o i n t e r i n t h e f i r s t word.
The t h i r d word i s t h e f i r s t dimension of t h e a r r a y ( o b t a i n e d by adding
1 t o t h e M i n a D I M A ( M , N ) s t a t e m e n t because t h e f i r s t s u b s c r i p t i s
always 0 ) , and t h e l a s t word i s t h e second dimension o f t h e a r r a y
( o b t a i n e d by adding 1 t o t h e N i n t h e aforementioned D I M s t a t e m e n t f o r
I f t h e a r r a y i s uni-dimensional,
t h e second
t h e same r e a s o n ) .
To l o c a t e t h e n t h element i n t h e a r r a y ,
INBRTS
dimension i s zero.
performs the following c a l c u l a t i o n :
A d d r of A(M,N)=3*[M+(DIM1+1)*N]+Addr of A ( 0 , O )

A p o i n t e r t o t h e s t a r t of t h e Array Symbol Table less 1 ( f o r u s e i n an
The
index r e g i s t e r ) can be found i n f i e l d 0 a t l o c a t i o n ARSTRT.
scheme f o r a r r a y s is:
I

Array
Symbol

Tab l e
(FIELD X)

Array
CDF Y

A(M,N)
~

1) I
I

CDF10

(FIELD Y)

CDF X

FIELD J8
ARSTRT

11.5.3

The S t r i n g Symbol T a b l e

The S t r i n g Symbol T a b l e has s u c c e s s i v e three-word

11-8

e n t r i e s as follows:

-MAXIMUM

# OF CHARS I N STRING

CDF FOR STRING
POINTER TO STRING
The f i r s t word is a 1 2 - b i t p o i n t e r t o t h e c o u n t word o f t h e s t r i n g .
The second word o f each e n t r y i s a CDF f o r t h a t c o u n t word, and t h e
t h i r d word o f t h e e n t r y i s t h e maximum l e n g t h of t h e s t r i n q ( i n number
n e g a t i v e number.
A
of c h a r a c t e r s ) s t o r e d as a 2's complement
p o i n t e r t o t h e s t a r t of t h e S t r i n g Symbol Table ( l e s s 1) can be found
i n f i e l d 0 location STSTRT.
N o t e t h a t t h e maximum number o f
c h a r a c t e r s i n t h e s t r i n g r e p r e s e n t s t h e amount of s p a c e a l l o c a t e d f o r
t h e s t r i n g ; t h e amount of s p a c e a c t u a l l y used i s r e p r e s e n t e d by t h e
c o u n t word which i s s t o r e d w i t h t h e s t r i n g .
,

The scheme for simple s t r i n g s i s :
INT (max. l e n g t h + l ) +1

words long

String
Symbol
Table
(FIELD X)

-MAX

LENGTH

entry 2

CDF Y

String
A$

POINTER TO A$

(FIELD Y )

entry 1

COUNT FOR A$

L ---------------FIELD

11.5.4

CDF10

f> CDF X

STSTRT

1 POINTER TO STRING SYMBOL T A B L E - 1 1

The S t r i n g Array T a b l e

The S t r i n g Array T a b l e c o n s i s t s of c o n s e c u t i v e 4-word
each e n t r y as follows:
DIMENSION O F A$(O)
-MAXIMUM

#OF CHARS I N A$ (0)

CDF FOR A$ (0)
POINTER TO A$ (0)

11-9

entries,

with

The f i r s t word contains a p o i n t e r t o t h e c o u n t word of s t r i n g A$(O)
and t h e second word c o n t a i n s a CDF f o r t h i s count.
The t h i r d word h a s
t h e maximum l e n g t h ( i n c h a r a c t e r s ) of each element i n t h e array s t o r e d
as a 2 ' s complement n e g a t i v e number. The l a s t word c o n t a i n s t h e
dimension o f t h e s t r i n g a r r a y , o b t a i n e d by adding 1 t o t h e M i n a D I M
s t a t e m e n t of t h e form D I M A$(M,N) because t h e f i r s t element i s always
A$ ( 0 ) . A p o i n t e r t o t h e s t a r t o f t h e S t r i n g Array Table less 1 can be
found i n f i e l d 0 a t l o c a t i o n SASTRT.
The scheme f o r s t r i n g a r r a y s is:
String
Array
Table

M+1

(FIELD

entry 2

-N
CDF Y

COUNT

POINTER TO
AS ( B )

entry 1

FIELD PI

S t r i n g Array
AS ( M t N )
(FIELD Y)
AS (8)

COUNT

CDF10

I CDF X

SASTRT

I POINTER TO START O F S T R I N G ARRAY TABLE -1 1

To locate t h e n t h element of t h e s t r i n g

array,

INBRTS

performs

the

f o l l o w i n g calculation:

addr of A$(N)=addr
where Z = i n d i v i d u a l element l e n g t h
11.6

FLOATING-POINT PACKAGE

The INBRTS f l o a t i n g - p o i n t package i s permanently r e s i d e n t , and as such
it is r e a d i l y a v a i l a b l e f o r use by assembly language r o u t i n e s f o r
floating-point c a l c u l a t i o n s .

11.6.1

F l o a t i n g - P o i n t Accumulator

One o f t h e operands of e v e r y f l o a t i n g - p o i n t o p e r a t i o n i s t h e F l o a t i n g
Accumulator
(FAC) , and t h e r e s u l t of a l l f l o a t i n g - p o i n t o p e r a t i o n s
(except FPUT) i s always l e f t i n t h e FAC. The FAC i s found a t EXP
HORD, and LORD on page 0 w i t h s t a n d a r d PDP-8 23-bit f l o a t i n g - p o i n t

11-10

format:

LORD

LOW MANT I S S A

H I G H MANTISSA

mantissa

exponent

The f l o a t i n g - p o i n t accumulator i s t o f l o a t i n g - p o i n t i n s t r u c t i o n s what
t h e hardware accumulator i s t o PDP-8 machine language i n s t r u c t i o n s .

F l o a t i n g - P o i n t Routines

11.6.2

The f o l l o w i n g f l o a t i n g - p o i n t r o u t i n e s are
s u b r o u t i n e use :
Function
S t a r t i n g Address
ADD
SUBTRACT
MULTIPLY
DIVIDE
INVERSE SUBTRACT
INWRSE D I V I D E
LOAD FAC
STORE FAC

available

for

user

Operation

FFADD

FAC+FAC+OPERAND

FFSUB
FFMPY
FFDIV

FACeFAC-OPERAND
FACyFAC *OPE RAND
FAC+FAC/OPEFWND
FAC+OPERAN D- FAC
FACI-OPE FWD/FAC
FAC+OPERAND
OPE RAND+FAC

FFSUBl
FFDIVl
FFGET
FFPUT

The symbol "+" means "is replaced by".

Note t h a t t h e store f u n c t i o n (FFPUT) i s t h e o n l y o p e r a t i o n i n which
t h e r e s u l t i s n o t l e f t i n t h e FAC Note a l s o t h a t FFPUT i s a
n o n - d e s t r u c t i v e store, i.e., t h e FAC i s t h e same a f t e r t h e store
o p e r a t i o n as b e f o r e .
There are two c a l l i n g sequences f o r t h e f l o a t i n g - p o i n t r o u t i n e s , e a c h
Mode
w i t h a d i f f e r e n t method f o r p a s s i n g t h e address of t h e operand.
1 is t h e m o s t e f f i c i e n t , and can b e used whenever t h e operand is i n
field 0.
Mode 2 is t h e f i e l d independent c a l l , b u t i s more core
e x p e n s i v e t h a n mode 1.
The m o d e b e i n g used i s determined as f o l l o w s :

I f t h e c o n t e n t s of the AC i s non-zero on e n t r y , t h e
i s m o d e 2.

I f the c o n t e n t s of t h e AC i s zero on e n t r y , t h e l o c a t i o n FF
examined.
I f FF i s a l s o z e r o , m o d e 1 is t h e c a l l i n g mode.
FF i s non-zero, mode 2 i s used.

mode

used

The c a l l i n g modes are as follows:

Mode 1

- address of operand follows c a l l t o f l o a t i n g - p o i n t r o u t i n e .
CLA
DCA FF

/SWITCH

11-11

FF=O FOR MODE 1

is
If

JMS I POINTER

...

(operand a d d r e s s )

/JUMP TO FLOATING-POINT ROUTINE
/12 B I T ADDRESS OF OPERAND

POINTER,(starting a d d r e s s )
Mode 2

/FLOATING- POINT ROUTINE
/STARTING ADDRESS.
address of operand i n AC on c a l l t o f l o a t i n g - p o i n t routine.
CLA IAC
DCA FF

CDF N
TAD OPADDR

JMS I POINTER
(unused)
POINTER, ( s t a r t i n g a d d r e s s )
OPADDR, (operand)

/FF SWITCH NOT EQUAL TO o FOR
/MODE 2
/DF TO FIELD OF OPERAND
/ADDRESS OF OPFRAND
/JUMP TO FLOATING-POINT ROUTINE

/THIS LOCATION UNUSED
/RETURNS HERE.
/ADDRESS OF FLOATING-POINT ROUTINE
/ADDRESS

OF OPERAND

Both modes return w i t h a c l e a r AC and t h e data f i e l d set t o 0 .
Note
t h a t t h e s w i t c h FF i s n o t a l t e r e d by t h e r o u t i n e s t h e m s e l v e s , hence it
i s o n l y n e c e s s a r y t o set i t when d e s i r e d t o change modes, n o t b e f o r e
e v e r y call.
The mode 2 c a l l always r e t u r n s t o t h e second i n s t r u c t i o n f o l l o w i n g t h e
c a l l , s k i p p i n g the word -following t h e JMS.
S i n c e t h i s word i s
completely unused, it i s a good location f o r constant s t o r a g e .

JMS

The FF s w i t c h is n e c e s s i t a t e d by t h e s p e c i a l case when i t i s d e s i r e d
t o r e f e r e n c e an operand l o c a t e d a t l o c a t i o n 0 i n a f i e l d o t h e r t h a n
field 0.
I f t h e FF s w i t c h were n o t p r e s e n t , t h e f l o a t i n g - p o i n t
package would examine t h e AC, f i n d i t empty, and u s e t h e a d d r e s s i n
t h e word f o l l o w i n g t h e c a l l , s i n c e t h e r e i s no way o f d i s t i n g u i s h i n g
an empty AC from an operand a d d r e s s of 0 loaded i n t o t h e AC.
The FF
s w i t c h , t h e n , i s used t o t e l l t h e f l o a t i n g - p o i n t package whether t h e
zero AC m e a n s "mode 1 c a l l " o r "operand a t 0 " .
INBRTS m a i n t a i n s l i n k s f o r FGET and FPUT on page 0 of f i e l d
p r o v i d i n g convenient access t o t h e s e f r e q u e n t l y used r o u t i n e s .
Page 0
Link N a m e

Routine Linked

FGETL
FPUTL

FFGET
FFPUT

Examples :
Some examples of INBRTS f l o a t i n g - p o i n t code:
1.

Routine t o calculate X + 2 + 2 X + 1

CLA

11-12

DCA FF
JMS I FGETL
X
JMS I FMPYLK
X
JMS I FPUTL
Y
J
M
S I FGFTL

/OPERAND ADDRESS WILL
/FOLLOW CALLS (MODE 1)
/LINK I S ON PAGE 0

/x * x
/SAVE

X42

/LOAD

X AGAIN

JMS I FMPYLK
TWO
JMS I FADDLK

/2x+1

ONE
JMS I FADDLK
Y

/X'42+2X+1

.
.
0

FADDLK
FMPYLK

Two

,
,

FFADD
FFMPY

0002
2000
0000
0001
2000
0000

ONE ,

/2 x

/RESULT NOW I N FAC
/LINK TO ADD ROUTINE
/LINK TO FLOATING MULTIPLY
/FLOATING POINT CONSTANT

/2.0
/FLOATING POINT CONSTANT

/1.0
/VARIABLE

0 . .
0 . .
0 . .

/FLOATING-POINT

0
0
0
2.

TEMPORARY

Rou-ine
-0 at 1 5
successive
floating-point
numbers s t a r t i n g a t location 0 of f i e l d 2.

START

ALOOP

,
,

MINUS5

FADDLK ,
OPADDR
K3I

CLA
DCA OPADDR
J
M
S I FCLR
IAC
DCA FF
CDF 20
TAD OPADDR
JMS I FADDLK

-5
TAD OPADDR
TAD K 3
DCA OPADDR
IAZ MINUS5
JMP ALOOP
HLT
FFADD
0

/FIRST OPERAND AT LOCATION 0
/ZERO FAC

/CALLS

ARE MODE 2

/OPERAND ADDR I N AC
/CALL ADD ROUTINE
/LOCATION UNUSED, S O WE USE
/ I T AS A COUNTER
/UPDATE OPERAND ADDFESS
/DONE?
/NO
/YES-ANSWER
I N FAC.
POINTER TO ADD ROUTINE
/POINTER TO OPERAND
/EACH OPERAND I S 3 WORDS LONG.

11-13

F l o a t i n g - P o i n t Operations

11.6.3

There are also f o u r simple f l o a t i n g - p o i n t o p e r a t i o n s t h a t
t h e FAC and are a v a i l a b l e t o user s u b r o u t i n e s .
Function

S t a r t i n g Address

NEGATE
NORMALIZE

FFNEG
FFNOR
FFSQ
FACCLR

SQUARE
CLEAR

operate

Operation
FAC+-FAC
NORMAL1 Z E*FAC

FAC-AC
FAC4

*FAC

These f u n c t i o n s are a l l called by simple JMS, and r e t u r n w i t h t h e
Page 0 Links are maintained f o r n e g a t e , n o r m a l i z e , and
hardware AC=O.
clear.
Page 0 Link

Routine

F'NEGL

FFNEG
FFNOR
FACCLR

FNORL
FCLR

11.7

INBRTS SUBROUTINES

There are several subroutines i n INBRTS which can be u s e f u l t o
assembly language f u n c t i o n s .
A d i s c u s s i o n of each of t h e s e r o u t i n e s
follows.
They are i d e n t i f i e d i n t h e d i s c u s s i o n by t h e t a g f o r t h e i r
s t a r t i n g a d d r e s s , and a l l t a g s r e f e r r e d t o can b e found i n t h e symbol
table.
11.7.1

Subroutine ARGPRE

Subroutine ARGPRE i s used t o locate scalar Table.
When c a l l e d , it
u s e s t h e r i g h t m o s t 8 b i t s (0-225 decimal) o f location INSAV as t h e
e n t r y number t o be found, and on r e t u r n , t h e d a t a f i e l d i s s e t t o t h e
f i e l d o f t h e variable and t h e AC p o i n t s t o t h e exponent word o f t h e
variable. ARGPRE is c a l l e d v i a a JMS, and is used most o f t e n i n
p a s s i n g arguments t o and from t h e u s e r s u b r o u t i n e .
(See S e c t i o n 11.8)
Example:

Load t h e FAC w i t h t h e t h i r d variable i n t h e S c a l a r Table.
CLA
TAD C2

DCA INSAV
IAC
DCA FF
JMS I ARGPRL
JMS I FGETL

(unused)
HLT

c2 I
ARGP RL ,

/WE WANT ENTRY # 3 , BUT
/SINCE THE FIRST ONE IS 0 ,
/LOAD INSAV WITH 2

/SET FF SWITCH
/CALL ARGPRE
/THE

AC AND DATA

FIELD

/ARE SET, S O THIS IS A
/MODE 2 CALL.

2
ARGPRE

11-14

11.7.2

Subroutine XPUTCH

Subroutine XPUTCH i s u s e d - t o p u t ASCII c h a r a c t e r s i n t o t h e t e r m i n a l
ring buffer,
When c a l l e d , t h e 8 - b i t ASCII c h a r a c t e r is i n t h e
On r e t u r n , t h e AC i s c l e a r e d .
Note that
r i g h t m o s t 8 b i t s o f t h e AC.
u n l e s s t h e r i n g b u f f e r i s empty, XPUTCH does n o t cause any c h a r a c t e r s
t o be p r i n t e d ; it merely p l a c e s t h e c h a r a c t e r i n t h e t e r m i n a l r i n g
buffer.
I f t h e r i n g b u f f e r i s f u l l t h e system w i l l w a i t u n t i l i t can
p l a c e t h e c h a r a c t e r i n t h e r i n g b u f f e r . A page 0 l i n k t o XPUTCH i s
maintained a t l o c a t i o n XPUT.
Example : Put a carriage r e t u r n / l i n e f e e d combination i n
buffer.

terminal

/LOAD CR INTO AC
/CALL XPUTCH V I A PAGE 0 L I N K
/LOAD LINE FEED INTO AC
/PUT I N BUFFER

CLA
TAD 0215
J
M
S I XPUT
TAD K212
JMS I XPUT

K215,
K212,

the

/ASCII CODE FOR CR
/ASCII CODE FOR LF

215
2 12

. Subroutine PSWAP

11,7 3

Under normal c o n d i t i o n s , INBRTS r u n s w i t h t h e OS/8 page 17600 p o r t i o n
of t h e r e s i d e n t monitor moved t o t h e h i g h e s t page o f c o r e (second
h i g h e s t page i f TD8/E system). PSWAP i s used t o swap t h i s page back
Prior t o calling
and f o r t h p r i o r t o doing any o p e r a t i o n s w i t h OS/8.
OS/8, PSWAP should be used t o restore t h e page 17600 r e s i d e n t t o
17600, and when OS/8 o p e r a t i o n s are complete, PSWAP should be c a l l e d
a g a i n t o swap t h e 17600 r e s i d e n t back up t o h i g h core. A page 0 l i n k
t o PSWAP i s maintained a t location PlSWAP,
Example: The following code uses t h e USR i n OS/8 t o perform
on the f i l e BASIC.DA on t h e systems device.

.
.

CLA

JMS I PlSWAP
CLA IAC
CIF 1 0
JMS I K7700

mm
0
HLT
J M S I PlSWAP

/AC SHOULD BE 0 ON CALL
/RESTORE OS/8 PAGE 17600 RESIDENT
/DEVICE # FOR SYS: IS 1

/CALL USR
/LOOKUP
/POINTER TO FILE NAME
/CONTAINS LENGTH ON RETURN
/ERROR RETURN
/SWAP OS/8 RESIDENT BACK
/TO H I G H CORE

.
11-15

LOOKUP

NOTE

I f PSWAP i s used, it must be executed an
When t h e assembly
even number o f t i m e s .
language f u n c t i o n i s c a l l e d , t h e page
17600 r e s i d e n t i s a t h i g h core; when t h e
f u n c t i o n r e t u r n s t o INBRTS, t h e 17600
r e s i d e n t must be back i n high core. On
TD8E systems
interrupts
should
be
disabled before
calling
PSWAP
and
reenabled a f t e r l a s t c a l l .
Subroutine UNSFIX

11.7.4

Subroutine UNSFIX i s used t o f i x a p o s i t i v e , 1 2 - b i t , magnitude o n l y
i n t e g e r from t h e FAC and r e t u r n w i t h t h e r e s u l t i n t h e hardware AC.
The range of t h e f i x e d i n t e g e r i s 0-4095; an a t t e m p t t o f i x a number
l a r g e r t h a n 4095 o r a n e g a t i v e number w i l l cause a n "FO" o r 'IFM"
error, r e s p e c t i v e l y .
UNSFIX i s c a l l e d v i a simple JMS, and a page 0
l i n k t o UNSFIX i s maintained, c a l l e d INTL.
UNSFIX d e s t r o y s t h e
c o n t e n t s of t h e FAC.
Example: The f o l l o w i n g code u s e s t h e FAC1 as a count of t h e number
t i m e s t o r i n g t h e b e l l on t h e t e r m i n a l .

.
.

BELLOP

CLA
JMS I INTL
CIA
DCA COUNTR
TAD K207
JMS I XPUT
ISZ COUNTR
JMP BILLOP

K207,

11.7 5

/FIX THE FAC TO 12-BIT INTEGER
/NEGATE THE INTEGER
/AND STORE AS COUNT
/ASCII FOR BELL
/PUT I N RING BUFFER
/RIGHT NUMBER YET?
/NO-RING ANOTHER BELL

20 7

Subroutine STFIND

Subroutine STFIND i s used t o locate a s t r i n g v a r i a b l e o r t h e f i r s t
When c a l l e d , i f t h e l i n k i s non-zero,
element of a s t r i n g a r r a y .
STFIND l o o k s f o r an e n t r y i n t h e S t r i n g Array Table.
I f t h e l i n k is
z e r o , STFIND uses t h e S t r i n g Symbol T a b l e .
For s t a n d a r d s t r i n g
v a r i a b l e s , the r i g h t m o s t 8 b i t s o f l o c a t i o n INSAV are used as t h e
number of the e n t r y t o be obtained; for s t r i n g array variables t h e
l a s t 5 b i t s are used.
On r e t u r n s from STFIND, t h e AC c o n t a i n s a CDF
t o t h e f i e l d o f t h e s t r i n g s p e c i f i e d , l o c a t i o n STRPTR p o i n t s t o t h e
f i r s t word (count word) o f t h e s t r i n g , l o c a t i o n STRMAX h o l d s t h e
m a x i m u m l e n g t h of t h e s t r i n g (as a n e g a t i v e number), and location
STRCNT contains t h e actual number o f c h a r a c t e r s i n t h e s t r i n g (as a
n e g a t i v e number).
STFIND i s used m o s t o f t e n i n p a s s i n g arguments t o
and from u s e r f u n c t i o n s .

11-16

Examples :
1. To f i n d s t r i n g number 7
TAD K6
DCA INSAV
CLL
JMS I S T F I N L

K6,

STFINL,

STFIND

11.7.6

To f i n d t h e f i r s t element of s t r i n g a r r a y number 2.
TAD K 1
DCA INSAV
CLL CML
JMS I S T F I N L

K1,
STFINL

/THE NUMBERING STARTS WITH
/SET UP STFIND POINTER
/WE WANT SIMPLE STRING
/CALL STFIND

/THE

SECOND ENTRY

/WE WANT STRING ARRAY
/CALL STFIND

1
STFIND

Subroutine BSW

Subroutine BSW i s used t o swap t h e two h a l v e s of t h e hardware AC.
BSW
i s c a l l e d by a simple JMS, and a page 0 l i n k c a l l e d BSWL i s
maintained.
11.7.7

Subroutine MPY

Subroutine MPY i s a 12-by-12-bit b i n a r y m u l t i p l y r o u t i n e . The AC i s
m u l t i p l i e d by t h e c o n t e n t s of l o c a t i o n TEMP3 ( b o t h numbers are t r e a t e d
as 1 2 - b i t , unsigned i n t e g e r s ) , and on r e t u r n , t h e high-order b i t s
of t h e r e s u l t are i n TEMP6, and t h e low-order b i t s of t h e r e s u l t a r e
i n t h e AC. The page 0 l i n e t o MPY i s MPYLNK.
11.7.8

Subroutine DLREAD

S u b r o u t i n e DLREAD i s used t o r e a d t h e n e x t w o r d of t h e i n c o r e DATA
l i s t i n t o t h e AC.
I f t h e r e i s no m o r e d a t a i n t h e DATA l i s t , a DA
error message r e s u l t s .
Example:

Read t h e n e x t number from t h e DATA l i s t i n t o t h e FAC.
CLA

JMS I DLREAL
DCA EXP
JMS I DLREAL
DCA HORD
JMS I DLREAzl
DCA LOSR

DLREAL,

/READ EXPONENT WORD INTO AC
/STORE I N FAC
/READ HIGH MANTISSA FROM L I S T
/STORE HIGH MANTISSA WORD
/READ LOW MANTISSA FROM L I S T
/STORE LOW MANTISSA WORD

DLREAD

11-17

11 7.9

Subroutine ABSVAL

Subroutine ABSVAL i s used t o t a k e t h e a b s o l u t e v a l u e of t h e FAC.
If
t h e FAC i s p o s i t i v e , ABSVAL i s e s s e n t i a l l y a NOP; i f t h e FAC i s
n e g a t i v e , i t i s negated b e f o r e r e t u r n .

11.8

P A S S I N G ARGUMENTS TO THE USER FUNCTION

INBRTS c a l l s t h e u s e r assembly language f u n c t i o n w i t h
a
JMP
instruction.
P r i o r t o e x e c u t i n g t h a t J M P , it p l a c e s t h e f i r s t numeric
argument i n t h e FAC, t h e second i n Scalar Table e n t r y 0 , t h e t h i r d i n
Scalar T a b l e e n t r y 1, etc., u n t i l t h e argument l i s t i s satisfied.
If
any s t r i n g arguments are used, t h e f i r s t i s found i n t h e SAC and t h e
second is p o i n t e d t o by S t r i n g Table e n t r y 0. The u s e r f u n c t i o n
o b t a i n s t h e s e arguments as needed by c a l l i n g t h e r o u t i n e s ARGPRE and
STF’ND a p p r o p r i a t e l y .
A l l u s e r f u n c t i o n s occur i n FIELD 1.

FIELD 1 core usage i s as follows:

I
I
BASIC

12400

BASIC CODE
USER FUNCTIONS
FILE I / O

12000
BASIC CODE
FILE I / O
NON-INTERRUPTING
USER FUNCTIONS

11400

PROCESS I / O

10000
The p r o c e s s I/O area which e x t e n d s up t o 1 4 0 0 i n f i e l d 1 i s used by
The area from 1 4 0 0 t o 1777 i n f i e l d 1 i s a
t h e real-time f u n c t i o n s .
s h a r a b l e area: I f any f i l e I / O i s done, t h i s area w i l l be allocated
f i r s t f o r t h e b u f f e r space: i f no f i l e I / O i s done, t h i s area may be
used f o r n o n - i n t e r r u p t i n g u s e r f u n c t i o n s .
F i n a l l y , i f no f i l e I / O or
non-interrupting
u s e r f u n c t i o n s are b e i n g used, BASIC i n t e r p r e t i v e
code can extend i n t o these l o c a t i o n s .
T h e area f r o m 2000 to 2 3 7 7 i n f i e l d 1 i s another sharable area:

f i l e s are needed a t runtime, t h i s w i l l be t h e second area allocated:
i f t h i s area i s n o t needed f o r 2 f i l e s , l a r g e BASIC programs can u s e
t h i s area f o r extended core, o r i t may be used as a r e s i d e n t area f o r
any t y p e s o f u s e r f u n c t i o n s .
Users adding t h e i r own f u n c t i o n s t o t h e BASIC Run-Time System have to
provide i n f o r m a t i o n t o INBRTS so it may handle core
-_ c o r r e c t l y . T h i s
w i l l be d e t a i l e d later.

11-18

11.8.1

I n t e r f a c i n g FIELD 1 Code w i t h FIELD 0 S u b r o u t i n e s

For convenience a r o u t i n e r e s i d e s i n FIELD 0 (CALLFO) which w i l l
a c c e p t t h e word following t h e J M S as t h e FIELD 0 s u b r o u t i n e t o c a l l .
An argument can be passed t o t h e subroutine i n t h e AC.
Return t o
FIELD 1 occurs a t argument: +l.
The sequence looks as follows:

I n FIELD 1
TAD AC

CIF 0
JMS I [CALLFO
subroutine t o call
r e t u r n occurs h e r e w i t h Data FIELD-1
The f o l l o w i n g f u n c t i o n t a k e s t h e f i r s t t w o numeric
performs t h e operation on them s p e c i f i e d i n A$:

arguments

and

for

and

UDEF EXM(X,A$,Y)
LET Z=EXM ( 2 , "PLUS" ,1)

Legal values f o r A$ are s t r i n g s beginning w i t h
" M I " f o r "MINUS".

"PL"

"PLUS"

I f t h e f u n c t i o n i s t o r e t u r n any value, t h a t value should be l e f t i n
t h e FAC on r e t u r n .
The u s e r f u n c t i o n must always r e t u r n by a JMP I
ILOOP i n FIELD 0 w i t h t h e d a t a FIELD 0.
To g e n e r a t e a f a t a l I A ( i l l e g a l argument) error message, perform a JMP
t o location I A i n INBRTS.
/ENTRY POINT, DATA FIELD=O

Em,
DCA I (INSAV
TAD I FlSACP
TAD PL

/INITIALIZE FOR ARG 0
/GET FIRST 2 CHARS OF A$ FROM SAC

SZA CLA
JMP EMINUS
CIF 0
JMS I (CALLFO
ARGPRE
CIF0
JMS I (CALLFO
FFADD
RETURN, CDF CIF 0
JMP I (ILOOP
EMINUS, TAD I FlSACP
TAD M I
SNA CLA
JMP ISMINS

CIF CDF 0
JMP I ( I A
ISMINS, CIF 0
JMS I (CALLFO
ARGPRF,

11-19

CIF 0
JMS I (CALLFO
FFSUB
JMP RETURN
PL *
MII

-20 14
-1511

11.8.2

Using t h e USE Statement

I f t h e assembly language f u n c t i o n needs t o know t h e l o c a t i o n o f an
a r r a y ( f o r b u f f e r space, m u l t i p l e argument p a s s i n g , a r r a y argument),
The USE s t a t e m e n t p l a c e s t h e o c t a l
t h e USE s t a t e m e n t i s necessary.
number f o r t h e a r r a y s p e c i f i e d i n t o l o c a t i o n USECON.
By u s i n g t h i s
v a l u e as an index i n t o t h e Array Symbol Table, t h e a r r a y s p e c i f i e d can
be l o c a t e d and used by t h e assembly language f u n c t i o n , as necessary.

For example: The h y p o t h e t i c a l assembly language f u n c t i o n PLT r e q u i r e s
a 100-word b u f f e r ,
To a s s u r e a l l o c a t i o n o f t h i s b u f f e r , t h e BASIC
u s e r of PLT i s i n s t r u c t e d t o dimension a 34-element a r r a y and use it
i n a USE s t a t m e n t b e f o r e c a l l i n g t h e PLT f u n c t i o n .

In BASIC:
10
20
30
40

REM DEFINE THE USER FUNCTION
UDEF PLT (X,Y)
REM ALLOCATE A 34 ELEMENT ( 1 0 2 WORDS) ARRAY FOR A BUFFER
DIM B ( 3 4 )

100 USE
110 Y=PLT (3,2.8)

.
0

The f u n c t i o n PLT f i n d s B as f ollotm :
PLT

TAD USECON
CLL RTL
TAD ARSTRT
DCA XR5
TAD CDF10
DCA .+I
TAD I XR5
DCA BPTR
TAD I X R 5
DCA BCDF
TAD I XR5
DCA DIM1
TAD I XR5
DCA DIM2

/GET ENTRY NUMBER O F B
/MULTIPLY BY 4 (EACH ARRAY TABLE
/ENTRY I S 4 WORDS LONG)
/MAKE POINTER INTO ARRAY TARLE
/AND SAVE I T
/GET CDF TO SYMBOL TABLE F I E L D
/PUT INTO L I N E
/CHANGE DF TO SYMBOL TABLE F I E L D
/GET POINTER TO B ( 0 )
/SAVE FOR LATER
/GET CDF FOR B (0)
/SAVE FOR LATER
/GET ARRAY DIPENSION 1
/GET ARRAY DIMENSION 2

11-20

N o t e t h a t t h e USE s t a t e m e n t merely p a s s e s an e n t r y number t o t h e
assembly language function:
a l l a c t u a l parameters must be o b t a i n e d
from t h e Array Symbol Table u s i n g t h a t e n t r y number as an index. Note
a l s o t h a t t h e p h y s i c a l l o c a t i o n o f a r r a y s passed i n such a f a s h i o n can
be almost anywhere i n core, and a f i e l d boundary may f a l l w i t h i n t h e
array.

11.9

INBRTS I / O

11.9.1

Terminal I / O

INBRTS d r i v e s t h e t e r m i n a l asynchronously by m a i n t a i n i n g a c h a r a c t e r
t e r m i n a l o u t p u t b u f f e r and u s i n g i n t e r r u p t s .
The procedure i s as
follows :
1.

C h a r a c t e r s are i n s e r t e d i n t o t h e t e r m i n a l r i n g b u f f e r by
c a l l i n g s u b r o u t i n e XPUT.
I f t h e r i n g b u f f e r i s f u l l , XPUT
w a i t s u n t i l a c h a r a c t e r i s p r i n t e d and a s l o t i s f r e e .

INBRTS p r i n t s a c h a r a c t e r from t h e r i n g b u f f e r
f l a g comes up.

whenever

the

Assembly language f u n c t i o n s are f r e e t o u s e t h e r i n g b u f f e r v i a XPUT.

11.9.2

INBRTS F i l e Formats

BASIC f i l e s are formatted as follows:
1.

Numeric f i l e s - Numeric f i l e s are f o r m a t t e d as c o n s e c u t i v e
3-word f l o a t i n g - p o i n t numbers,85 t o each 256-word OS/8 block.
The l a s t word i n each block i s unused.
There is no
end-of-f i l e marker.

ASCII F i l e s
ASCII f i l e s are s t o r e d i n OS/8 ASCII format,
t h a t i s , t h r e e 8 - b i t c h a r a c t e r s packed t o e v e r y t w o words as
follows :

' H I ORDER
CHAR 3

CHAR 1

LO ORDER
CHAR 3

CHAR 2

11-21

11.9.3

INBRTS B u f f e r Space

L o c a t i o n s 11400-12377 i n INBRTS are devoted t o f i l e b u f f e r space.
B u f f e r s are a l l o c a t e d as t h e y are needed, t h e lowest f r e e b u f f e r
always b e i n g a l l o c a t e d first. A map of c u r r e n t l y a l l o c a t e d b u f f e r s i s
maintained on page 0 , c a l l e d BMAP.
B i t s i n t h e m a p are on i f t h e
b u f f e r is a l l o c a t e d , o f f i f t h e b u f f e r i s f r e e . B i t 1 1 r e p r e s e n t s t h e
b u f f e r from 11400-11777,
b i t 10 f o r 12000-12377.
I f any o f t h e
b u f f e r s are not available because t h e pseudo-code or variable s p a c e
e x t e n d s below 12400, t h e corresponding BMAP b i t s are set when INBRTS
is started.

11.9.4

INBRTS Device D r i v e r Space

The o n l y a v a i l a b l e d e v i c e d r i v e r s are t h e r e s i d e n t d e v i c e d r i v e r s .
No
o t h e r space i s a l l o c a t e d f o r d e v i c e d r i v e r s .
On TD8E systems
units
0 and 1 are r e s i d e n t , on RK8E systems a l l o f u n i t 0 i s r e s i d e n t .
N o t e t h a t assembly language f u n c t i o n s t h a t are used i n programs

which
do n o t r e q u i r e more than one f i l e open a t once may wish t o u s e some o f
t h e b u f f e r space f o r t h e i r own purposes.
T h i s space can b e a l l o c a t e d
by s e t t i n g a p p r o p r i a t e b i t s i n BMAP, by modifying INBRTS i n i t i a l i z e
code ( f o l l o w s TAG TTYBUF)
A f t e r t h e b i t s are s e t , INBRTS w i l l n o t
use t h i s space i n subsequent FILE commands.

11.9.5

The INBRTS I / O T a b l e

INBRTS keeps t r a c k o f t h e s t a t u s of each of t h e f i l e s which may be
open simultaneously by means o f t h e I / O t a b l e .
S t a r t i n g a t FILE1, it
has t w o 13-word e n t r i e s , l a b e l e d FILE1 and FILE2.
Each
name
corresponds t o t h e number s p e c i f i e d i n t h e f i l e statement which opened
t h a t f i l e , and t h e format of each e n t r y is as f o l l o w s :
HEADER WORD

POSITION OF PRINT HEAD (FOR COLUMN FORMATTING) OR DEVICE NAME
MAXIMUM FILE LENGTH OR DEVICE NAME
FILE NAME
FILE NAME
FILE NAME
FILE NAME
STARTING ADDRESS OF BUFFER ( I N FIELD 1)
CURRENT BLOCK I N BUFFER
READlWRITE POINTER INTO BUFFER
HANDLER ENTRY POINT
STARTING BLOCK NUMBER FOR FILE
ACTUAL FILE LENGTH
The header word bits have significance as follows:

B i t Positions

Meaning

0-3

OS/8

4-5

C u r r e n t c h a r a c t e r number f o r unpacking ASCII f i l e s

0 i f t h e c u r r e n t b u f f e r l o a d h a s n o t been changed

1if

number f o r d e v i c e

the

current

11-22

buffer load has

been a l t e r e d

0 i f device i s f i l e s t r u c t u r e d

1 i f device i s read/write only
8

0 i f t h e h a n d l e r i s 1 page long

1 i f it i s a 2-page h a n d l e r

0 i f f i l e is fixed length

1 i f variable length
10

0 i f more d a t a i n f i l e

1 i f EOF has been seen
11

0 i f f i l e numeric

1 i f f i l e ASCII

11.10

INTERFACING THE ASSEMBLY LANGUAGE FUNCTION TO INBRTS

A l l assembly language f u n c t i o n s are r o u t i n e s , c a l l e d by a JMP

through
t h e U s e r Function Table. This table, which b e g i n s a t l o c a t i o n 1560 i n
INBRTS, c o n t a i n s absolute p o i n t e r s t o t h e s t a r t i n g a d d r e s s e s of each
of t h e user assembly language f u n c t i o n s .
U s e r f u n c t i o n s must be
o r i g i n e d t o run i n FIELD 1, and must r e t u r n t o INBRTS v i a a JMP I
ILOOPL i n FIELD 0. T o i n t e r f a c e a set o f u s e r f u n c t i o n s t o INBRTS,
perform t h e following o p e r a t i o n s :
1.

Assemble
all
the
u s e r assembly
language
functions;
t n e e n t r y t o t h e f u n c t i o n s must be i n FIELD 1. E n t r y i s w i t h
t h e d a t a FIELD set t o 1.
FIELD 1 PAGE 0 s c r a t c h l o c a t i o n s and u s e f u l FIELD 0
are given i n S e c t i o n 11.11.3.

pointers

.R PAL8
*NWNAME

Load t h e user f u n c t i o n s and 1NBRTS.BN i n t o
Absolute Loader, and save t h e core image.

core

with

the

.R ABSLDR
"INBRTS ,USER$

Using O S / 8 ODT, modify t h e U s e r Function Table i n INBRTS
which starts a t 1574, e n t e r i n g p o i n t e r s t o t h e u s e r assembly
language f u n c t i o n s . Unmodified t a b l e e n t r i e s are 2 3 6 ( 8 ) ; replace t h e s e e n t r i e s with the s t a r t i n g addresses ( p o i n t e r s l t o
the u s e r assembly language function.
Starting a t location
enter
the p o i n t e r s i n t h e table i n t h e e x a c t
15748
corresponding o r d e r i n which t h e f u n c t i o n s appear i n t h e UDEF
s t a t e m e n t which d e f i n e s them.

11-23

ODT

1574/236 2000 (LF')
1575/236 2020

.SAVE SYS INBRTS 0-7577,lOOOO-lXXXX; 7605
where XXXX r e p r e s e n t s t h e
functions.

high

core

address

the

user

I n t h e procedure above t w o f u n c t i o n s are i n t e r f a c e d which s t a r t a t
l o c a t i o n s 2000 and 2010 r e s p e c t i v e l y
LF i n d i c a t e s p r e s s i n g the LINE
FEED key.

Example: There are t h r e e assembly language f u n c t i o n s i n o u r package,
called PLT, H I , and LO.
The BASIC u s e r i s i n s t r u c t e d t h a t when h e
u s e s t h i s f u n c t i o n package, PLT, H I and LO must be d e f i n e d ' i n t h a t
o r d e r . The f u n c t i o n f i l e s , t h e n , look l i k e :
Function Source (USER.PA)
*2000
HI,

/ENTRY POINT FOR HI
/ORDER OF ENTRY POINTS IS
/NOT CRITICAL

.
0

PLT ,

CIF CDFO
JMP I [ILOOP
/ENTRY FOR PLT

CIF CDFO
JMP I [ILOOP

Lo,

.
.

/ENTRY

FOR LO

CIF CDFO
JMP I [ILOOP

T o e n t e r t h e s e t h r e e f u n c t i o n s i n t o t h e u s e r f u n c t i o n t a b l e i n INBRTS,

t h e procedure is:

GET SYS :INBRTS

.ODT
1574/236
1575/236
1576/236

PPPP (LF)
HHHH (LF)
LLLL

'4C

.SAVE SYS :INBRTS

11-24

where PPPP, HHHH, and U L L r e p r e s e n t o c t a l s t a r t i n g addresses f o r PLT,
H I , and LO r e s p e c t i v e l y .
LF i n d i c a t e s p r e s s i n g t h e LINE FEED key.
NOTE

INBRTS e s t a b l i s h e s c a l l s t o t h e u s e r f u n c t i o n by
s e t t i n g up a one-to-one correspondence between t h e
p o i n t e r s a t 1574 and t h e f u n c t i o n names p r e s e n t i n
a UDEF statement.
Therefore, t h e order of t h e
p o i n t e r s must e x a c t l y correspond t o t h e order of
I f t h e BASIC
t h e f u n c t i o n d e f i n i t i o n s i n UDEF.
u s e r wants t o use only t h e n ( t h ) f u n c t i o n i n a
given
u s e r package, h e must s t i l l d e f i n e n
f u n c t i o n s i n t h e UDEF s t a t e m e n t , though t h e f i r s t
n-1 may be dummies.

For example: A package of f o u r assembly
f u n c t i o n s t h a t u s e arguments as follows.

language

ONE ( X )
Two ( X , Y )
THR ( X , Y , Z )
FOU ( X , Y , Z , A )

I f a BASIC u s e r wishes t o use only
ONE, t h e UDEF would look l i k e :

one

function

1 0 UDEF ONE (X)

I f t h e BASIC u s e r wants t o use f u n c t i o n s
FOU, t h e UDEF would look l i k e :

ONE

and

1 0 UDEF ONE(X) ,DUA(D) ,DUB

For this u s e r , DUA and DUB are dummy u s e r f u n c t i o n
names which are never called t h e y merely set up
t h e r i g h t correspondence
between
names
and
pointers.

The easiest way t o a s s u r e t h a t t h e p o i n t e r s are
e s t a b l i s h e d c o r r e c t l y i s t o provide t h e u s e r of an
assembly language f u n c t i o n package w i t h a s e t of
complete UDEF s t a t e m e n t s t h a t d e f i n e a l l f u n c t i o n s
c o r r e c t l y , and i n s t r u c t him t o use t h e complete
s e t o f UDEF's each t i m e .

11.11

GENERAL CONSIDERATIONS AND HINTS

11.11.1

Routines Unusable by Assembly Language Functions

Because only one o v e r l a y is r e s i d e n t a t any t i m e , assembly language
f u n c t i o n s can only c a l l r o u t i n e s i n t h e o v e r l a y which i s r e s i d e n t when
e x e c u t i n g , they cannot use any r o u t i n e s t h a t reside i n any o f t h e t w o
o t h e r overlays.
Following i s a l i s t of t h e INBRTS f u n c t i o n s and
r o u t i n e s grouped by overlay.

11-25

Function

Routine N a m e
A r i t h m e t i c Overlay
FFATN

Arctangent Function

FFCOS

Cosine Function

FFE XP
EXPON

Exponential Function (eX )
B
Power Function (A )

INT

Signed i n t e g e r Function

FFLOG

Naperian log Function

SGN

Sign Function

FFSIN

Trigonometric S i n e Function

RND

Random Number g e n e r a t o r

FROOT

Square root Function

S t r i n g Overlay
ASC

S t r i n g Function ASC

CHR

CHR$ Function

DAT

DAT$ Function

LEN

S t r i n g l e n g t h Function

POS

S t r i n g s e a r c h Function

SEG

S t r i n g segmenting Function

STR

STR$ Function

VAL

VAL Function

TRC

Trace Function

B i l e Overlay

CLOSE
OPENAF

F i l e manipulation r o u t i n e s

OPENAV
OPENNF
OPENNV

11-26

11.11.2

Using OS/8

So l o n g as t h e assembly language f u n c t i o n i s c a r e f u l l y designed t o
p r o t e c t a l l core areas b e i n g used by INBRTS, t h e r e are no r e s t r i c t i o n s
Once t h e page 17600 r e s i d e n t monitor
on t h e f u n c t i o n ' s use of OS/8.
h a s been restored, t h e OS/8 U s e r S e r v i c e Routine (USR) may be c a l l e d
a t w i l l , and f i l e s may be located, used, and closed again.
If the
u s e r ' s BASIC program does n o t need f u l l f i l e c a p a b i l i t i e s , t h e
assembly language f u n c t i o n is f r e e t o u s e t h e b u f f e r s p a c e from
11400-12377.
The assembly language f u n c t i o n should be c a r e f u l ,
however, t o check t h e b i t maps and s t a t u s words on page 0 t o make
certain a given area i s f r e e b e f o r e u s i n g it. Note t h a t t h e system
d e v i c e d r i v e r may be used without r e s t o r i n g t h e page 17600 r e s i d e n t :
r e s t o r a t i o n i s only r e q u i r e d when it i s desired t o use t h e USR.

11.11.3

Page 0 Usage

Following is a map of t h e INBRTS page 0 usage.
Locations marked w i t h
an * may be used by t h e assembly language f u n c t i o n w i t h o u t s a v i n g t h e
contents

FIELD 0 , PAGE 0
0-2
3- 7
10-15 *
16-17
20-30
30-36
37-62
63-67
73-107
110-161
162-177

Interrupt vector
System parameters and temps
Index r e g i s t e r s
System p o i n t e r s
Compiler-INBHTS communieation
System r e g i s t e r s
F l o a t i n g - p o i n t package area
System r e g i s t e r s
Constants
Links t o INBRTS s u b r o u t i n e s
I/O Table pointers

FIELD 1, PAGE 0

0- 17
20-33
34-40

Unused ( a v a i l a b l e f o r u s e r )
S c r a t c h Area
P o i n t e r s f o r FIELD 0 r o u t i n e s

Assembly language f u n c t i o n s are f r e e , o f course, t o u s e any of the
p o i n t e r s or c o n s t a n t s , b u t they must be i n t a c t when c o n t r o l i s
r e t u r n e d t o INBRTS.

11.12

ASSEMBLY LANGUAGE FUNCTION EXAMPLE

To i l l u s t r a t e t h e material i n the p r e v i o u s s e c t i o n s , an example of a
complete assembly language f u n c t i o n f o l l o w s . N o t e t h a t t h i s example
i s t u t o r i a l i n n a t u r e : it is meant t o i l l u s t r a t e argument p a s s i n g and

g e t t i n g along with
language f u n c t i o n s .

INBHTS

rather

a t y p i c a l use f o r assembly

functions and an a d d i t i o n t o the
The f u n c t i o n performed i s r e a d i n g a s t r i n g from

The example consists of t w o user

i n t e r r u p t s k i p chain.

than

11-27

a second t e r m i n a l and s t o r i n g it i n a s t r i n g variable; t h e s t r i n g w i l l
be p r i n t e d on t h e main console terminal i f a c a r r i a g e return i s

entered.

100
105
110
120
130
140
150
160
170
180
200
2 10
220

2 30
300

310
320
330
340
350
360
37.0
380
1000
1010
1020
1030
10 40
1050
1060
5000

REM
REM
REM
REM
REM
REM
REM
REM
REM
REM

DIM

T H I S IS A DEMONSTRATION INDUSTRIAL
BASIC PROGRAM
WHICH WILL RUN COMPUTE BOUND AND
ACCEPT CHARACTERS FROM A SECOND TELETYPE
U S I N G THE INTERRUPT FACILITY.
THE RUN TIME SYSTEM HAS BEEN MODIFIED
TO ADD CODE TO THE INTERRUPT S K I P CHAIN
AND INSERT THE ADDRESSES OF THE USER
FUNCTIONS

A$(40)

UDEF T T l ( X ) , T T 2 $ ( A $ )
PRINT 'I I M RUNNING"
TIMER .1 THEN 1000
FOR I = 1 TO 5 E 5

J = J+1
I F J 500 THEN 350
PRINT I
J = O
NEXT I
TIMER 0 THEN 1000
PRINT "DONE"
STOP
X = TTl(0)
I F X=O THEN 1040
I F X 0 THEN 1050
PRINT "*****"; A$
DISMISS
A$ = TT2$ (A$)
DISMISS
END

11-2 8

11.13

L I N K I N G INTO THE INTERRUPT SKIP CHAIN

I f t h e u s e r desires t o p r o c e s s I / O from an I / O
d e v i c e which i s
c u r r e n t l y n o t supported by INBRTS and t h e i n t e r r u p t f a c i l i t y must be
used, t h e u s e r must add code t o t h e i n t e r r u p t s k i p chain.
The u s e r may allocate t h e second f i l e I / O b u f f e r a t l o c a t i o n 1 2 0 0 0 f o r
s t o r a g e of t h e i n t e r r u p t d r i v e n code and t h e s k i p c h a i n . I f t h i s i s
done, remember t o mark t h i s b u f f e r as " i n use" so t h a t INBRTS w i l l n o t
t r y t o allocate it.
F i l e I / O b u f f e r 1 may n o t be used f o r
i n t e r r u p t i n g code, b u t can be used f o r n o n - i n t e r r u p t i n g u s e r f u n c t i o n s
because it i s swapped by t h e OS/8 system when INBRTS c a l l s upon t h e
USR t o perform services.
NOTE

INBRTS g e t s an i n t e r r u p t r e g u l a r l y once
every 1/50 second f o r c l o c k s e r v i c e s .
Obviously i n t e r r u p t s are o f f i n t h e s k i p
c h a i n , t h e r e f o r e no computations o f any
t y p e should be performed.

Actual l i n k i n g i n t o t h e s k i p c h a i n i s performed as follows:
. R ABSLDR
*INBRTS

(UFUNCS are any u s e r f u n c t i o n s )

*UFUNCS$
ODT

6773/0000 addr

addr i s

the

FIELD

1 address

the

user

continuation of the skip chain
1041/6764 6773

.SAVE SYS I N B R T S .

save arguments as needed
f u n c t i o n s and INBRTS.
NOTE

E n t r i e s i n the u s e r f u n c t i o n table may
also be modified a t t h i s t i m e . Location
6773 i n FIELD 0 is a CIF CDF 10. I f t h e
u s e r w a n t s t h e d a t a f i e l d t o be zero
upon e n t r y t o t h e FIELD 1 p o r t i o n of t h e
s k i p , he must change t h e CIF CDF 10 t o
CIF 10.

11-29

FIELD 1
/EXAMPLE

OF ASSEMBLY LANGUAGE INTERFACE
TO INBRTS

/DEFINE USED IOTs
ASKF = 6331
AKRB = 6336
ATSF = 6 3 4 1
ATLS = 6346
ATCF = 6 3 4 2
/DEFINE REFERENCED LOCATIONS I N INBRTS
FACCLR =
STRLEN =
SACPTR =
CALLFO =
INTRET =
ILOOP =
HORD =
/THE ADDITION TO THE INTERRUPT SKIP CHAIN
*2 00 0
TTYSCN,

AKSF
JMP TESTOUT

AKRB
DCA CHAR
TESTOUT , ATSF
SKP
ATCF
C I F CDF 0
JMP I (INTRET

/ I S READER FLAG UP
/NO..
/YES
GET CHARACTER
/SAVE I T
/ I S PRINTER FLAG U P
/NO..
/YES.
.CLEAR I T
/RETURN BACK TO F I E L D 0

....
..

/ROUTINE TO DETERMINE FUNCTION DESIRED BY
/ALTERNATE TELETYPE

/ I F FAC =O, NO ACTIVITY, I F F A 0 0 ADD CHARACTER TO
/CURRENT STRING, AND I F FAC<O PRINT STRING
TT1,
TAD CHAR
/GET CHARACTER
SNA
/ I S ONE REALLY THERE?
JMP NOCHAR
I N P U T RECENTLY
/NO...NOTHING
ATLS
IT
/YES...ECHO
AND (77
/MAKE I T 6 - B I T FOR INTERNAL FORMAT
DCA SVCHAR
/SAVE CHARACTER FOR STRING FUNCTION
DCA CHAR
/CLEAR LAST TYPED FLAG
CIF 0
/USE CALLFO INTERFACE FUNCTION
JMS I (CALLFO /TO CALL ROUTINE WHICH CLEARS
FACCLR
/FAC
TAD SVCHAR
/SEE I F CHARACTER
TAD (-15
/WAS A CARRIAGE RETURN
SNA CLA
/ S K I P I F NOT
CLL CML RAR
.MAKE AC NEGATIVE
/YES.
IAC
/SET AC TO 1 OR 4 0 0 1
NOCHAR,
CDF 0
/PLACE RETURN ARGUMENT I N

11-30

DCA I (HORD
C I F CDF 0
JMP I (ILOOP

/FAC HIGH ORDER WORD
/RETURN
/TO INTERPRETER

/ROUTINE TO CONCATENATE LAST TYPED CHARACTER
/ON ALTERNATE TELETYPE TO STRING I N THE STRING
/ACCUMULATOR
/SHOULD ONLY BE CALLED I F TT1 RETURNED A
/POSITIVE NUMBER

TT2 I

PUTIN

HIGHPT,

SVCHAR,
CHAR
PTR,

CDF 0
TAD I (STRLEN
CIA
CLL RAR
TAD I (SACPTR
DCA PTR
SNL
JMP HIGHPT
TAD I PTR
TAD SVCHAR
DCA I PTR
CMA
TAD I (STRLEN
DCA I (STRLEN
C I F CDF 0
JMP I (ILOOP

/INBRTS INFO. I S I N F I E L D 0
/GET CURRENT STRING LENGTH
/MAKE I T P O S I T I V E
/CONVERT TO WORD OFFSET FROM CHAR OFFSET
/POINTS TO SAC-1
/SAVE I T
/ L I N K = l MEANS 2ND CHAR I N WORD
/WILL BE F I R S T CHARACTER I N WORD
/GET UPPER HALF OF LAST CHARACTER
/ADD I N NEW CHARACTER
/PLACE BACK INTO SAC
/BUMP LENGTH UP BY ONE, BUT I T I S
/NEGATIVE

TAD SVCHAR
CLL RTL
RTL
RTL
JMP PUTIN

/CHARACTER MUST GO INTO HIGH
/ S I X B I T S O F WORD

/RETURN
/TO INTERPRETER

/FINISH

PUTTING I T I N

0
0
0

11-31

APPENDIX A
OS/8

A.l

BASIC STATEMENT, COMMAND, AND FUNCTION SUMMARY

ELEMENTARY OS/8

Statement

BASIC STATEMENTS
Example of Form

DEV: F i lemane e x t

Explanation
Stops e x e c u t i o n o f t h e
c u r r e n t program, r e t r i e v e s
t h e program named i n t h e
CHAIN s t a t e m e n t from t h e
s p e c i f i e d d e v i c e and f i l e ,
compiles
the
chained
program
and
begins
e x e c u t i o n o f t h e program.

CHAIN

DATA

DATA xl,x2,

,xn

Values x l through xn are
to
be
associated with
corresponding v a r i a b l e s i n
a
€U3AD s t a t e m e n t .
The
values
may
be
either
or
strings.
numerics
S t r i n g s must be e n c l o s e d
by q u o t a t i o n marks.

DEF

DEF FNB(x) = f (x)

The u s e r may d e f i n e h i s
own f u n c t i o n
t o be called within h i s
program by p u t t i n g a DEF
s t a t e m e n t a t t h e beginning
of
a
program.
The
f u n c t i o n name b e g i n s w i t h
FN and must have t h r e e
letters.
The
argument
l i s t i n t h e f u n c t i o n may
c o n t a i n as many
as
4
numeric
and
2
string
arguments.

...

DEF FNB(x,y) = f ( x , y )

DIM

For numerics:
D I M v l ( n 1 ) , v2(nl,m2)

Enables t h e u s e r t o create
a table o r a r r a y w i t h t h e
specified
number
of
elements where v i s t h e
v a r i a b l e name and n and m
are t h e maximum s u b s c r i p t
values.
Any number of
a r r a y s can be dimensioned
i n a s i n g l e D I M statement.

For s t r i n g s :

I is the length of s t r i n g
variable v l $ ,
K i s t h e number of s t r i n g s
and L is t h e l e n g t h of
s t r i n g s of s t r i n g variable
v2$.
S t r i n g s longer than

DIM v l $ (I),v2$ (K,L)

A- 1

8
characters
must
be
dimensioned.
String
tables are i l l e g a l .

END

L a s t statement
in
the
program.
Signa 1s
completion of t h e program.

FOR-TO-STEP

FOR v=xl TO x2 STEP x3

Used to

implement loops:
the
variable v is s e t
equal t o t h e expression
xl.
From t h i s p o i n t t h e
loop c y c l e is completed
V
f ollowinq
which
i s incremented a f t e r each
cycle
by x3 u n t i l i t s
v a l u e i s g r e a t e r t h a n x2.
I f STEP x3 i s o m i t t e d , x3
is assumed t o +l. x3 may
also be n e g a t i v e .
I f x3
i s p o s i t i v e and x l > x 2 , t h e
loop i s never executed.

GOSUB

GOSUB x

A l l o w s the user t o enter a
subroutine
at
several
p o i n t s i n t h e program.
Control t r a n s f e r s t o l i n e
X.

GOTO

GO TO n or
GOTO n

Transfers control t o
line
n
and
continues
e x e c t i o n from t h e r e .

IF-G(Tr0

I F f l r f 2 GOTO n

Same as IF-THEN.

IF-THEN

I F f l r f 2 THEN n

I f the
relationship
r
between t h e e x p r e s s i o n s f l
and f 2 i s t r u e , t r a n s f e r s
c o n t r o l t o l i n e n; i f n o t ,
continue
in
regular
sequence

GO TO or

I f f l and f 2 are s t r i n g
t h e y are compared on t h e
b a s i s o f t h e A S C I I numeric
v a l u e of each c h a r a c t e r i n
See paragraph
the string.
7.1.4 f o r d e t a i l s .
INPUT

Causes t y p e o u t o f a

INPUT vl,v2,...,vn

the user and waits for the

u s e r t o supply t h e v a l u e s
of
the
variables
vl
through vn. See paragraph
3.5.1 f o r INPUT r u l e s .

LET

Assigns t h e v a l u e of
to
expression
f
v a r i a b l e V.
The w o r d
i s optional.

LETv-f

A-2

the
the
LET

Used t o t e l l t h e
to
return
to

computer
t h e FOR
s t a t e m e n t and e x e c u t e t h e
loop
again u n t i l v i s
g r e a t e r t h a n or e q u a l t o
terminal
value
i n FOR
statement
(or
V
is < terminal
value
if
increment < O )

NEXT V

PRINT al,a2,...,an

P r i n t s t h e v a l u e s of t h e
specified arguments, which
may be v a r i a b l e s , t e x t , or
format c o n t r o l characters
(, or : I .
See
paragraph
f o r format c o n t r o l
3.5.2
and p r i n t i n g r u l e s .

RANDOMIZE

Generates new
random numbers.

READ

READ v i , ~ 2 , . . . , ~ n

Variables v l through vn
are a s s i g n e d t h e v a l u e of
t h e corresponding numbers
or s t r i n g s i n the DATA
list.

REM

When typed as t h e first
t h r e e letters of a l i n e
e v e r y t h i n g between R E M and
end of l i n e i s ignored t o
allow t y p i n g of remarks
w i t h i n t h e program.

RESTORE

Sets p o i n t e r back t o t h e
beginning of t h e l i s t o f
DATA values.

RETURN

Transfers control t o
statement
following
l a s t GOSUB

STOP

UDEF

UDEF f u n c t i o n name (arguments)

sets

the
the

When encountered i n t h e
program t h e STOP s t a t e m e n t
t e r m i n a t e s execution.

The UDEF s t a t e m e n t i s used

t o d e f i n e t h e s y n t a x of a
call
to
a
user-coded
machine language f u n c t i o n
( f u n c t i o n name) w i t h i t s
a s s o c i a t e d arguments.

A- 3

,...,vn

USE

USE v l , v 2

CONTACT-THEN

CONTACT v THEN n

The
USE
statement
i d e n t i f i e s t h e l i s t s and
a r r a y s r e f e r e n c e d by
a
machine
user- coded
language f u n c t i o n .
Define t h e l i n e number (n)
t o schedule when a c o n t a c t
i n t e r r u p t o c c u r s on p o i n t
V.

COUNTER-THEN

COUNTER v THEN n

Define t h e l i n e number (n)
to
schedule
when
the
counter point v reaches
zero.

TIMER-THEN

TIMER v THEN n

Define t h e l i n e number (n)
t o schedule when t h e t i m e
v h a s elapsed.
Continue
to
cycle
until
timer
d i sab l e d

DISMISS

A.2

OS/8

E x i t from u s e r
interrupt
mode
main l i n e code.

DISMISS

rocess
-p resume

BASIC FILE STATEMENTS

See Chapter 1 0 of t h i s manual f o r d e t a i l s r e g a r d i n g t h e
BASIC f i l e s t a t e m e n t s and f i l e d e s c r i p t i o n s .

use

OS/8

St aternen t

Example of Form

Explanation

CLOSE #

CLOSE #N:

Closes a f i l e N p r e v i o u s l y
by
a
FILE I N
opened
s t a t e m e n t where N i s t h e
numerical e x p r e s s i o n f o r
t h e f i l e number.

FILE #
FILEV #
FILEN #

FILEVN #

FILE #n:s
FILEV #n:s
FILEN #n:s
FILEVN #n:s

These s t a t e m e n t s ,
open,
respectively, a fixed
l e n g t h A S C I I , variable
length ASCII, fixed length
numeric,
and
variable
l e n g t h numeric f i l e , where
1 or
n h a s a v a l u e of
2 and s i s
a
string
expression w i t h a value of
DEV:FILE.EX.
DEV
is
system handler.

INPUT #

INPUT I N :

I F END #

I F END

vl,v2

,...,vn

#N THEN n

A- 4

Reads v l through
f i l e number N.

I f an a t t e m p t
made
t o read

h a s been
or w r i t e

from

PRINT #

PRINT #N:

a1 ,a2,.

..,an

beyond t h e l a s t datum i n
file
number N , c o n t r o l
p a s s e s t o l i n e number n.

Writes t h e values of t h e
arguments i n t o f i l e number
N.

RESTORE #

Sets
pointer
back
to
b e g i n n i n g o f f i l e number

RESTORE #N

A.3

O S / 8 BASIC CONTROL COMMANDS

Command

Example of Form

BYE

Explanation
Exits

from

BASIC

and

returns

control t o Keyboard Monitor.
CTRL/C

CTRL/C

execution of program
and
control t o OS/8 I n d u s t r i a l
BASIC e d i t o r .
In
editor
mode
r e t u r n s c o n t r o l t o O S / 8 Keyboard
Monitor.
Stops

returns

CTRL/O

Stops t h e l i s t i n g of t e x t
and
r e t u r n s control t o BASIC e d i t o r .

LIST

LIST
LI

L i s t s program w i t h heading.

LIST n
LI n

L i s t s program s t a r t i n g from

LISTNH
LISTNH n

Same as LIST and LIST n,
b u t heading suppressed.

NAME

NAME FILE.EX
NA FILE.EX

T h i s statement renames t h e c u r r e n t
program i n user core.

NEW

NEW FILE.EX

NE FILE.EX

Used t o name a program t o
created.
Performs an i n h e r e n t SCRATCH.

OLD
OL

OLD DEV: FILE.EX
OL DEV: FILE.EX

Performs i n h e r e n t SCRATCH and
retrieves a p r e v i o u s l y c r e a t e d f i l e
from t h e device s p e c i f i e d .

RUN

Compiles and e x e c u t e s t h e program
c u r r e n t l y i n core, w i t h heading.

RUNNH

RU"H

Compiles and executes t h e
c u r r e n t l y i n core, w i t h
suppressed.

SAVE

SAVE DEV?FILE.EX
SA DEV:FILE.EX

Saves t h e c u r r e n t program on t h e
device specified.

l i n e n , w i t h heading.

A- 5

program
heading

SCRATCH

A.4

SCRATCH

Deletes a l l program s t a t e m e n t s
from user core.

OS/8 BASIC FUNCTIONS
Explanation

Function
This f u n c t i o n
argument X.

returns

the

absolute

value

the

ASC (X)

This f u n c t i o n r e t u r n s t h e decimal A S C I I number
Appendix D) corresponding t o t h e c h a r a c t e r X.

(see

ATN ( X )

This function calculates t h e angle ( i n
t a n g e n t i s given by t h e argument X.

radians)

whose

is a numeric e x p r e s s i o n (modulo 6 4 ) which
is
t r u n c a t e d t o an i n t e g e r .
The decimal i n t e g e r i s
converted t o i t s e q u i v a l e n t A S C I I c h a r a c t e r
(see
Appendix D).
X

The c o s i n e f u n c t i o n i s used t o c a l c u l a t e t h e c o s i n e

an a n g l e s p e c i f i e d i n r a d i a n s .
This f u n c t i o n r e t u r n s t h e d a t a i n t h e
The argument X is a dummy argument.

form

MM/DD/YY.

T h i s f u n c t i o n c a l c u l a t e s t h e v a l u e of e(2.71828)
t h e t h e X power.

Used w i t h a DEF s t a t e m e n t t o d e f i n e a
T h e r e a f t e r used as any o t h e r f u n c t i o n .

user

This function r e t u r n s the g r e a t e s t
t h e v a l u e of t h e argument X.

integer

This function

returns

the

number

raised

function.
less

than

characters

s t r i n g XS.
The M G ( X ) f u n c t i o n c a l c u l a t e s t h e n a t u r a l l o g a r i t h m o f
X.

T h i s f u n c t i o n , which can be used o n l y i n a P R I N T
s t a t e m e n t , o u t p u t s t h e c h a r a c t e r whose decimal A S C I I
v a l u e i s X.
T h i s function is useful f o r outputting
non-printing characters

POS (XS,YS ,z 1

This function returns the location in s t r i n g X$ of the
f i r s t occurrence of s t r i n g Y$ s t a r t i n g w i t h t h e Zth
c h a r a c t e r i n s t r i n g X$.
See paragraph 7.2.4
f o r POS
function rules.

T h i s f u n c t i o n r e t u r n s a random number between 0 and 1.
This f u n c t i o n r e t u r n s t h e s u b s t r i n g of
between p o s i t i o n s Y and Z i n c l u s i v e l y .
7.2.5 for SEG$ f u n c t i o n r u l e s .

A-6

which i s
See paragraph

SGN ( X )

The s i g n f u n c t i o n r e t u r n s t h e v a l u e 1 i f X i s any
p o s i t i v e number, 0 i f z e r o , and -1 i f any n e g a t i v e
number.
This f u n c t i o n i s used t o c a l c u l a t e t h e s i n e of an a n g l e
specified i n radians.
The square root f u n c t i o n computes t h e
t h e a b s o l u t e value of an e x p r e s s i o n .

square

root

of
a

This f u n c t i o n c o n v e r t s t h e numeric value o f
s t r i n g which i s i t s decimal r e p r e s e n t a t i o n .

This f u n c t i o n which can o n l y be used i n
s t a t e m e n t , moves t h e p r i n t head t o p o s i t i o n X.

This f u n c t i o n t u r n s on t h e trace f e a t u r e i f x=l and
t u r n s o f f t h e trace f e a t u r e i f x=O. When t h e trace
f e a t u r e i s on, l i n e numbers are p r i n t e d between p e r c e n t
s i g n s as t h e l i n e s are encountered i n t h e program. The
f e a t u r e i s u s e f u l when debugging programs.
This f u n c t i o n r e t u r n s t h e number r e p r e s e n t e d by t h e
s t r i n g X$ which i s t h e decimal r e p r e s e n t a t i o n of a
number.

A. 5

INDUSTRIAL FUNCTIONS

Explanation

Function
ANI (P,G)

This f u n c t i o n r e a d s a n a l o g i n p u t p o i n t P a t g a i n G and
r e t u r n t h e value i n v o l t s .

AN0 (P ,VI

This f u n c t i o n loads t h e D/A p o i n t P w i t h t h e v a l u e V.
1 0 2 3 = f u l l scale
Ominimum

CLK (X)

I f t h e value of X is z e r o o r n e g a t i v e t h i s f u n c t i o n
If the
r e t u r n s t h e t i m e of day clock i n seconds.
value of X i s p o s i t i v e t h e t i m e of day c l o c k i s s e t
t o t h e value of X
14x486 4 00

CN1 (P)

This f u n c t i o n r e t u r n s t h e number of counts
u n t i l z e r o i n c o u n t e r P.

remaining

CNO (P V)

T h i s f u n c t i o n loads t h e c o u n t e r ( P ) such t h a t V i t e m s
w i l l be counted before t h e c o u n t e r (P) i n t e r r u p t s
(overflows)

RDI ( P , N )

This f u n c t i o n
through N.

SDo (P,N ,VI

This f u n c t i o n l o a d s t h e v a l u e V, i n b i n a r y ,
p o i n t ( s ) P through N ( r i g h t j u s t i f i e d ) .

returns

A- 7

the

value

point(s)

into

T h i s function return the r e s u l t s

the

s e n t t o p o i n t ( s ) P t h r u N.

W E (XI
STA (X)

These are U P I R I d e n t i f i c a t i o n Functions.
( R e f e r t o chapter 8, section 8.4).

CNT ( X )

Arguments are dummies.

A- 8

last

data

APPENDIX B

COMPILE-TIME DIAGNOSTICS

are

Compile-time d i a g n o s t i c messages typed o u t by OS/8 BASIC
form:

the

where XX i s t h e d i a g n o s t i c code and YY i s t h e l i n e number a t which t h e
error occurred.
D i a g n o s t i c Code

Explanation

Error i n CHAIN statement.

Error i n DEF statement.

Error i n D I M s t a t e m e n t s y n t a x or s t r i n g dimension
greater than 72, or a r r a y dimensioned t w i c e .

E r r o r i n f i l e number or filename d e s i g n a t i o n .

I n c o r r e c t F O R loop parameters o r FOR l o o p syntax.

Error i n
defined

THEN or GOTO missing from

function

arguments
IF

function

not

bad

statement,

relational operator.

error.

I/O

Missing e q u a l s i g n i n LET statement.

Statement too long (greater t h a n 80 characters).

Line number d e f i n e d more than once.
l i n e number b e f o r e l i n e i n error.

Missing END statement.

equals

Operand expected, n o t found.

Missing p a r e n t h e s i s o r error i n e x p r e s s i o n
parentheses.

within

Operand of mixed t y p e o r operator does n o t match
operands (e.g., A$=l and A&2 are b o t h i n c o r r e c t ) .

Line number missing a f t e r GOTO, GOSUB, or THEN.

Output f i l e error.

statement
statement.

B-1

without

corresponding

FOR

R e s u l t of either too
Pushdown stack overflow.
complex a s t a t e m e n t (or s t a t e m e n t s ) o r too many
n e s t e d FOR-NEXT loops

S t r i n g l i t e r a l too long or does n o t end i n quote.

Subscript o r f u n c t i o n argument error.

Symbol table overflow due t o too many v a r i a b l e s ,
l i n e numbers, or l i t e r a l s . Combine l i n e s u s i n g
b a c k s l a s h (Q t o condense program.

System

incomplete.

INBSIC.SV,

INBCMP.SV,

System
files
such
and 1NBRTS.SV missing.

Condense or CHAIN.

Program too big.

TI)

Too much data i n program.

Too many t o t a l characters i n t h e s t r i n g literals.

I n c o r r e c t real t i m e s t a t e m e n t s .

Error i n UDEF s t a t e m e n t .

FOR loop w i t h o u t corresponding NEXT s t a t e m e n t .

Undefined s t a t e m e n t number.
(i.e.,
statement
number mentioned i n s t a t e m e n t i s n o t i n program.)

Incorrect
statement

E x t r a characters a f t e r t h e logical and of l i n e .
(e.g.,
LET A=B.D
t h e dot a f t e r t h e B s u g g e s t s
t h a t B i s t h e end of t h e l i n e and t h e character
D appears extraneous.)

missing

B- 2

array

designator

USE

APPENDIX C
RUNTIME DIAGNOSTICS

Runtime d i a g n o s t i c messages typed o u t by OS/8 BASIC a r e i n t h e form:
XX AT LINE YYYYY

where XX is t h e d i a g n o s t i c code and YYY i s t h e l i n e number a t which
Most runtime errors s t o p e x e c u t i o n of the
t h e error occurred.
program.
Those errors which do n o t s t o p t h e program a r e termed
non-fatal (NF) and are i n d i c a t e d below.
Explanation

D i a g n o s t i c Code
BO

N o more f i l e b u f f e r s a v a i l a b l e .

I n q u i r e f a i l u r e i n CHAIN.

Device n o t found.

Lookup f a i l u r e i n CHAIN.

Filename n o t found.

Attempt t o read p a s t end o f d a t a l i s t .

Device d r i v e r
failure.

N o more room

Attempt t o d i v i d e by 0.

error.

Caused

hardware

I/O

f o r drivers.
Too
d e v i c e s used i n f i l e commands.

many

different

Result is

set

zero.

when

I/O

(NF)

Logical end o f f i l e .
Usually
device runs o u t o f medium.

caused

Attempt t o e x p o n e n t i a t e a
power.

E n t e r error i n opening f i l e . Device i s read o n l y
or t h e r e i s a l r e a d y one v a r i a b l e f i l e open on t h a t
d e v i c e or f i l e n o t found.

FILE busy.

OS/8

Attempt t o close or u s e unopened f i l e .

Attempt t o f i x minus number.
Usually
n e g a t i v e s u b s c r i p t s o r f i l e numbers.

I l l e g a l f i l e number.

Attempt t o f i x number g r e a t e r t h a n 4095.
Usually
caused by n e g a t i v e s u b s c r i p t s of f i l e numbers.

negative

number

A t t e m p t t o use a f i l e a l r e a d y i n use.

error while c l o s i n g variable f i l e .
read only on f i l e closed a l r e a d y .

c-1

Device i s

caused

Only 0,l and 2 are legal.

RETURN w i t h o u t a GOSUB.

Too many n e s t e d GOSUBs.

I l l e g a l argument i n UDEF f u n c t i o n call.

I l l e g a l DEV:filename s p e c i f i c a t i o n .

Inquire
found

A t t e m p t t o t a k e log o f n e g a t i v e number o r 0.

D r i v e r error w h i l e o v e r l a y i n g .
device hardware error.

Numeric or i n p u t overflow.

I l l e g a l argument i n POS f u n c t i o n .

Attempt to read p a s t end of f i l e .

S t r i n g too long (greater t h a n 72 characters) a f t e r
concatenating.

S t r i n g too long or undefined.

Attempt t o read s t r i n g from numeric f i l e .

S t r i n g t r u n c a t i o n on i n p u t .
allowed.
(NF)

S u b s c r i p t o u t of D I M s t a t e m e n t range.

A t t e m p t t o w r i t e s t r i n g i n t o numeric f i l e .

Attempt t o read variable l e n g t h f i l e .

Attempt t o w r i t e p a s t end o f f i l e (NF).

failure

The l i m i t i s 10.

opening

file.

Device

Caused

not

SYS

(NF)

Stores m a x i m u m l e n g t h

Added Run-Time Process I / O E r r o r s
BE

Width crosses module boundary.

DISMISS

executed

while

not

user

interrupt

routine.
GE

Module i s n o t t h e correct g e n e r i c code (rype).

I n v a l i d g a i n specified for analog i n p u t .

I l l e g a l g e n e r i c code (Module n o t s u p p o r t e d ) .

D a t a i t e m o u t of v a l i d range.

Channel n o t d e f i n e d a t system g e n e r a t i o n .

c-2

I l l e g a l channel (channel n o t i n v a l i d r a n g e ) .

Zero width or width n o t wide enough.

A t t e m p t to start:

too

many

timers,

counters

contacts.

T i m e too l a r g e ( 3 8 6 4 0 0 for c l o c k or timer.

c- 3

APPENDIX D
ASCII CONVERSION TABLE

Character

6-Bit O c t a l

Decimal

Character

6 - B i t Octal

Decimal

01
02
03
04
05
06
07
10
11
12
13
14
15
16
17
20
21
22
23
24
25
26
27
30
31
32
60
61
62
63
64
65

1
2
3
4
5
6
7
8
9
10
11
12
13
14

6
7
8
9
space

66
67
70
71
40
41
42
43
44
45
46
47
50
51
52
53
54

54
55
56
57
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
58
59
60
61
62
63
0
27

C
D
E
F

H
I
J
K
L

M
N
0

Q
R
S

T
U
V

w
X

0
1
2
3
4
5

I
n

#
$
%

' (apostr. 1
(

*
+
,(comma)

15
16
17
18
19
20
21
22
23
24
25
26
48
49
50
51
52
53

/
i

1
t

D- 1

55
56
57
72
73
74
75
76
77
00
33
34
35
36
37

29
30
31

APPENDIX E
OS/8

INDUSTRIAL BASIC SYSTEM BUILD INSTRUCTIONS

OS/8 I n d u s t r i a l BASIC i s d i s t r i b u t e d on D E C t a p e .
The D E C t a p e version
of O S / 8 I n d u s t r i a l B A S I C c o n t a i n s SAVE i m a g e s ( r e a d y - t o - r u n )
f o r each
of t h e OS/8 I n d u s t r i a l B A S I C system components as w e l l as b i n a r i e s f o r
each s y s t e m c o m p o n e n t . OS/8 I n d u s t r i a l BASIC, then, i s d i s t r i b u t e d a s
t h e following f i l e s :

File
-

D i s t r i b u t e d on:

Component

.
..
.

I N B S I C BN
INBSIC. SV
INBCMP BN
INRCMP S V
INBLDR. BN
INBLDR. S V
INBRTS BN

B i n a r y for editor
E d i t o r save image
C o m p i l e r binary
C o m p i l e r save image

EAEOVR. BN

O v e r l a y f o r KE-8/E EAE
( 8 / E w i t h KE-8/E EAE)
R u n t i m e s y s t e m save
image ( f r o m INBRTS BN)

INBRTS S V

DECtape

.
function

DECtape
DECtape

overlay
S t r i n g f u n c t i o n overlay
F i l e m a n i p u l a t i o n overlay

1NBSIC.SF
I N B S I C FF
A s s e m b l i n g the OS/8

made r b i n a r y
Loader save i m a g e
R u n t i m e system b i n a r y

Ar i t h m e t i c

I N B S I C . AF

DECtape
DECtape
DECtape
DECtape
DECtape
DECtape
DECtape

DECtape
DECtape

I n d u s t r i a l B A S I C sources

I n s t r u c t i o n s f o r assembling each of t h e O S / 8 I n d u s t r i a l B A S I C sources
follow.
PAL-8
( u n d e r O S / 8 ) i s used, and t h e d e s c r i p t i o n s r e p r e s e n t
OS/8 commands.
T o a s s e m b l e OS/8 I n d u s t r i a l B A S I C , a 12K machine i s
required.
The OS/8 BASIC sources are named as follows:
NAME.MM

where NN r e p r e s e n t s t h e version number.
f i l e s are n a m e d :
Name
-

first

Component

.
.

INBSIC. 01
INBCMP 0 1
INBLDR. 0 1
INBRTS 0 1

For t h e

E d i t o r Source
C o m p i l e r Source

Loader Source
R u n t i m e System Source

To assemble t h e e d i t o r :
.R PAL8
*DEV:INBSIC.BN

DEV:INBSIC.Ol

E-1

release,

the

To assemble t h e compiler:

.R PAL8
*DEV :INBCMP BN< DEV :INBCMF' 0 1

The runtime system s o u r c e is c o n d i t i o n a l i z e d f o r PDP-8/E
with
Assembly
instructions
f o r each o f t h e supported
c o n f i g u r a t i o n s follow.

EAE.

To assemble f o r PDP-8E w i t h o u t EAE:
.R PAL8
*DEV: INBRTS.BN<DEV:INBRTS.

Ol/K

T o assemble t h e run-time system o v e r l a y f o r PDP-8E,
PDP-8F o r
PDP-8/M
w i t h KE-8/E
EAE o p t i o n , p r e p a r e a f i l e c a l l e d EAE.PA

t h a t looks as follows:
EAE-1
PDP8E=1
PAUSE

Then :
.R PAL8
*DEV:EAEOVR. BN-DEV:EAE. PA, DEV: INBRTS

01 / ~

Making SAVE Images from Binary F i l e s :
T o create SAVE images of each o f t h e OS/8 I n d u s t r i a l
perform t h e f o l l o w i n g OS/8 commands.

BASIC

binaries,

For t h e editor:

R ABSLDR
*DEV:BASIC. BN$
SAVI3 SYS :BASIC; 3011

For t h e compiler:

.R ABSLDR
*DEV:BCOMP.BN$
.SAVE SYS :BCOMP; 7000
3.

For t h e l o a d e r :
.R ABSLDR
*DEV: INBLDR. BN$
SAVE SYS $ BLOAD: 7 6 05

For t h e runtime system:
.R ABSLDR
*DEV:INBRTS.BN$

(ifyou have no KE-8/E

E-2

EAE o p t i o n )

*DEV:INBRTS.BN,DEV:EAEOVR.BN$
( i f you have PDP-8/E, PDP-8M or
PDP-8F with KE-8/E EAE)
.SAVE SYS INBRTS 0-7577, 10000-11377; 7605
.SAVE SYS 1NBSIC.AF

3400-4577

.SAVE SYS 1NBSIC.SF

12000-13177

.SAVE SYS INBSIC-FF 13400-14577
NOTE
All BASIC system files must
t h e systems d e v i c e ( S Y S : ) .
5.

reside

A t t h i s p o i n t , I n d u s t r i a l BASIC i s ready t o run.

E-3

APPENDIX F

INDUSTRIAL BASIC SYSTEM GENERATION
Each
f u n c t i o n a l I / O module (analog i n p u t , analog o u t p u t , d i g i t a l
i n p u t , d i g i t a l o u t p u t ) o p e r a t e s on a continuous range of l o g i c a l
addresses.
The mapping between t h e l o g i c a l
address
and
the
corresponding p h y s i c a l address of t h e UDC module and subchannel i s
performed w i t h i n t h e system, based on t a b l e s which d e f i n e t h e UDC
c o n f i g u r a t i o n and which t h e u s e r g e n e r a t e s d u r i n g "SYSTEM GENERATION".
System g e n e r a t i o n i s t h e process o f s e t t i n g t h e f u n c t i o n a l module
t a b l e s f o r analog i n p u t , analog o u t p u t , d i g i t a l i n p u t , d i g i t a l o u t p u t ,
s p e c i f i n g t h e base of t h e contact modules, and t h e base of c o u n t e r
modules.
The f i r s t s t e p i s t o determine t h e c l a s s i f i c a t i o n of each p h y s i c a l
channel. The c l a s s i f i c a t i o n yroups are c o n t a c t s (W742) counter(W7341,
analog i n p u t (ADUO1) , analog o u t p u t (BA633) d i g i t a l i n p u t (W740) and
d i g i t a l output.
Once t h e channels are c l a s s i f i e d t h e I / O t a b l e i n
INBRTS may be generated.
The following i s a sample system g e n e r a t i o n
of t h i s set o f modules.

Slot
-

Module

Class
-

BW7 42
BW742
BW740
BW740
BM6 84
BM686
BM6 86
BW734
mu01

contact
contact
d i g i t a l input
d i g i t a l input
d i g i t a l output
d i g i t a l output
d i g i t a l output
counter
analog i n p u t

The t w o i n t e r r u p t i n g module t y p e s ( c o n t a c t s and c o u n t e r s ) r e q u i r e o n l y
t h e base address of t h e i n i t i a l contiguous p h y s i c a l channel o f each
module type.
The t w o module t y p e s do n o t have t o be a d j a c e n t t o each
o t h e r , b u t each module ( c o n t a c t s and c o u n t e r s ) MUST be i n contiguous
channe 1s.
Logical channels s t a r t a t t h e h i g h o r d e r b i t (or subchannel zero) of
t h e f i r s t p h y s i c a l channel of a given t y p e of f u n c t i o n a l I / O module
and c o n t i n u e s e q u e n t i a l l y i n t h e o r d e r t h e p h y s i c a l channels are
s p e c i f i e d i n t h e f u n c t i o n a l I / O table.
I f channels 5 , 7 , 9 are d i g i t a l i n p u t and t h e t a b l e e n t r i e s are i n t h a t
o r d e r , l o g i c a l channels 1 through 1 2 a r e on p h y s i c a l channel 5, w h i l e
25 through 36 would be on p h y s i c a l channel 9 (Note
t h e b r e a k s are
dependent on t h e number o f I/O p o i n t s or subchannels p e r module).

The tables are most simply a l t e r e d via OS/8 ODT;
a d d r e s s should be converted t o octal addresses.

F- 1

the

UDC

physical

The table addresses are:

DIGITAL INPUT

- 10600

DIGITAL OUTPUT

- 10610

ANALOG INPUT

- 10620

ANALOG OUTPUT

- 10630

- 7310
COUNTER - 7276

CONTACT

The sample system table would be altered as follows:
.GET SYS INBRTS

ODT

10600/7777

0203 (CR)

10610/7777
10611/7777

0405 (LF)
0677 (CR)

106201/7777

1077 (CR)

7276/7777

0007 (CR)

7310/0000

0 (CR)

.SAVE

SYS INBRTS

Notice that addresses are entered in octal numbers and if an odd
number of addresses exists the last entry is terminated by 77. A line
feed gives the next entry in the current table. The table generation
is terminated via CTRL/C and the SAVE command. The table may be
altered to reflect alteration in hardware configurations; the sequence
of channel entries determines the mapping into logical channels.

F- 2

APPENDIX G
O P T I M I Z I N G SYSTEM PERFORMANCE

There are s e v e r a l s t e p s t h e OS/8 I n d u s t r i a l BASIC u s e r can t a k e t o
speed up BASIC e x e c u t i o n and compilation t i m e s , t h u s speeding up OS/8
I n d u s t r i a l BASIC throughput rates. This appendix c o n t a i n s s u g g e s t i o n s
f o r improving system performance.

Bypassing t h e E d i t o r

The OS/8 I n d u s t r i a l BASIC compiler is c o n s t r u c t e d such t h a t i t w i l l
a c c e p t any source f i l e f o r i n p u t .
Thus, i t i s p o s s i b l e t o e x e c u t e an
a l r e a d y e x i s t i n g BASIC program d i r e c t l y , s a v i n g t h e overhead o f an OLD
and RUN command t o t h e e d i t o r . The format i s as follows:
.R INBCMP

*DEV:FILE.BA
I f OS/8 I n d u s t r i a l BASIC i s used i n t h i s f a s h i o n , it
OS/8
Monitor on completion, r a t h e r than t h e OS/8

returns

t o the
I n d u s t r i a l BASIC

editor.
Normal Usaqe

F a s t e r Equivalent

.R INBSIC
NEW OR OLD--FILE

*FILE

.R INBCMP

READY
RU”H
READY

I n g e n e r a l , use R INBSIC when:
a.
b.

C r e a t i n g new programs or modifying o l d programs
Debugging o l d programs

U s e R INBCMP:
a. To run e x i s t i n g programs
b.
I n BATCH stream t o run BASIC programs

Source f i l e s f o r u s e by INBCMP must conform t o t h e following r u l e s :

There should be no blank l i n e s .

Statements must be i n t h e
executed.

L i n e numbers are r e q u i r e d o n l y f o r s t a t e m e n t s t h a t are
r e f e r e n c e d i n IF, GOSUB, and GOT0 s t a t e m e n t s .
In other
words, i f t h e o n l y way a s t a t e m e n t may be reached i s f o r t h e
preceding s t a t e m e n t t o be executed, it does n o t r e q u i r e a
l i n e number.
I n t h e following example, t h e r e are
no
unnecessary l i n e numbers.

order

G-1

which

the

are

FOR I=1 TO 1 0
I F 1 1 2 THEN 400
PRINT I
GO TO 410
400 PRINT "TWO"
410 NEXT I
END

N o t e t h a t t h e s o u r c e f i l e can be created i n one of t w o ways: it may be
created i n t h e normal f a s h i o n w i t h t h e OS/8 I n d u s t r i a l BASIC e d i t o r

and saved ( i n which case a l l l i n e s w i l l c o n t a i n l i n e numbers), or i t
may be p r e p a r e d u s i n g any o f t h e o t h e r O S / 8 e d i t o r s (EDIT, TECO).
In
t h i s second case, t h e u s e r can t a k e advantage o f t h e e x t r a f e a t u r e s
supported by t h e s e s o p h i s t i c a t e d e d i t o r s o v e r t h e O S / 8 I n d u s t r i a l
BASIC e d i t o r .
2.

Placement of BASIC Overlays on SYS

For DECtape system u s e r s , t h e
improved by t w o simple s t e p s :
a.

the

U s e a DECtape d r i v e o t h e r t h a n DTA0 f o r DSK:

statement).
b.

performance

system

(via the
TD8E system may o n l y use d r i v e s 0 and 1.

can

ASSIGN

Place t h e OS/8 I n d u s t r i a l BASIC system f i l e s as close t o g e t h e r
on t h e SYS t a p e as p o s s i b l e .
The b e s t approach i s t o make a
"BASIC t a p e " c o n t a i n i n g o n l y t h e OS/8 system, P I P , and t h e
BASIC system image f i l e s .

Both a c t i o n s have t h e e f f e c t o f speeding up O S / 8 BASIC by t h e simple
r e d u c t i o n o f t h e t a p e motion r e q u i r e d f o r o v e r l a y i n g and compiling.
3.

Placement o f Function C a l l s Within BASIC Programs

M o s t o f t h e OS/8 BASIC f u n c t i o n s and f i l e o p e r a t i o n s reside i n one o f
t h e t h r e e system o v e r l a y s .
S i n c e t h e system o v e r l a y d r i v e r reads i n
an o v e r l a y o n l y i f t h e f u n c t i o n d e s i r e d i s n o t p r e s e n t i n t h e
c u r r e n t l y r e s i d e n t o v e r l a y , o v e r l a y i n g overhead c a n be reduced by t h e
simple mechanism of p l a c i n g c a l l s t o f u n c t i o n s t h a t reside i n t h e same
o v e r l a y as close as p o s s i b l e i n t h e BASIC program.
For example:

10 INPUT A$
20 Z$= SEG$(A$,1,6)
30 FILEN #1: Z$
40 I N P U T A$
50 Z$= SEG$(A$,1,6)
60 FILEN #2:Z$
The above BASIC program u s e s t h e f i r s t six c h a r a c t e r s of a s t r i n g
typed by t h e u s e r as a f i l e name t o open a BASIC f i l e .
It uses t h e
SEG$ f u n c t i o n , a F i l e command, t h e SEG$ f u n c t i o n , and t h e F i l e command
again.
Since SEG$ and FILE are i n d i f f e r e n t o v e r l a y s , t h e o v e r l a y e r
w i l l be used f o u r t i m e s .
A f a s t e r way t o accomplish t h e same
o p e r a t i o n s follows :
1 0 INPUT A$,B$
20 Z$=SEG$ (A$, 1,6)

30 X$=SEG$ (B$,1,6)
40 FILEN #1: Z$

G-2

50 FILEN #2: X$
The above only overlays t w i c e , saving considerable time i n t h e program
execution. The functions are grouped i n the overlays a s f o l l o w s :

Overlay 1 (1NBSIC.AF) : SIN,COS,ATN,LOG,EXP,RND,SQR,SGN,POWER(A
Overlay 2 (1NBSIC.SF) : ASC,CMR$,DAT$,LEN,POS,SEG$,STR$,VAL
Overlay 3 (1NBSIC.FF): CLOSE, FILE, FILEN, FILEV,FILEVN

G- 3

APPENDIX H
RUN-TIME
SYMBOL TABLE

/Q!3/8

INDUSTRIAL BASIC RUNTIME

b3U7
3S75
A6SVAL 2363
ACH
0045
ACL
08146
4CLO
0046
A C S A V E 6744
ACSR
6072
A C S R P T 4704
ACX
0044
AC0
8Q40
004s
AC1
AC2
0@42
A O C A L C 0636
ADFC
0705
ADFW
4747
AIROR
0043
AJT
6712
ALl
5057
ALlK
3774
AblP
6240
ALSPP 5140
ALlPT 4705
ALlPTR 5642
AMODE 2310
ANOLST 3 4 S i
ANOPTR 3406
ANITBL 0 6 2 0
ANOTBL 0630
ANOUT 0656
AN1
3775
AN2
3776
APQB0l 237Y
bRGET 6200
C R G E T K 55693
ARGETL 5444
ARGETP 6127
ARGPLK 4312
ARGPLL 3511
AHGPQL 4220
4 R G P R E 03a4
ARGPRL 1415
ARGSET 0 0 7 1
A R I T H A 6373

A
ABSV

ARJYP

4RRAYI
ARSTRT
ARTRAP
ASC

07@7

06B0

0022

4366
3487
ASeNOE 3243
ASCOLK 3457
ASCON 3667
ASCQUP 1260
ATABOF 0 4 1 0
ATABOL 1162

ATAN
4200
A T A N A l 4438
ATANA2 4436
ATANA3 4444
ATANB0 4425
A T A N B l 4433
ATANBi! 4 4 4 1
ATANB3 4447
A999
2507
BAUCHN 0855
EIADGC PI844
BAS
6627
B C G E T 3035
BCGETL 2776
BCPUT a745
BCPUTL 3034
BE
0047
BENO
5572
BKHERE 7347
B L I N I T 3352
tlLREAO 3 3 3 4
BMAP
Q(836
BO
4210
B R T S B 1216
8 S H F T 0427
B S T R T 5547
BSWL
0144
BSMP
6361
BUFASS 4222
BUFCHK 2706
UUFCHL (4147
Ul
4216
82
4211
CA0
4506
CAF
66817
CbLFFP 7243
CALL8E 63046
CALLF0 7 2 2 1
CALLOW 0 0 6 1
CBLK
3672
CC16
4414
cc3
4316
cc4
4315
CDFXNL OS34
CDF10 c1820
COFPS Bli125
COFPSL 0115
CDFPSU 0206
COFXX 2140
CDF0
0216
COFklB0 4 3 4 1
CDF10 6307
CDF20 4565
COIN
3623
CFETCH 1322

PALBnV7

9/20/73

C H A I N 3600
CHAR
0053
CHARNO 6677
CWAR3P 21146
CHAR3U 3064
CHK63 6604
CHKB4 6613
CHR
3400
CHRNOL 0 1 5 1
C I
3624
CL
3640
CLEANP 4243
CLENG 3442
CLF
3570
CLN
08130
C L O C K 7000
CLOS€ 34Q3
CLOSEB 3445
CLOSER 3405
CLPY
1115
CLPYl
1122
CLSTAG 3544
CMMA
6434
CM210 6674
CNOBMK 2765
CIUOBML 5 5 7 3
CNOEMP 3104
CbQCLL 0146
CNOCLR 3016
C k T B A S 7276
CNTCBP 6666
CNTCBS 7310
C N T C O M 1254
ChfCST 1331
CNTCT 1106
C N T C T I 7122
CNTERI 1110
CNTFNC 0527
CNTFUC 7170
C N T I N 1314
ChTLC 7215
CNTOUT 1277
C N T R C T 1107
ChTSW
1077
ChTSWi! 1104
CCJMBNE 2766
COMLOP 2527
COMMA 2512
COMMAS 2551
COMMON 0200
COYONP 0 0 4 1
C O M X I T 0475
C O N T A C 1327
CONTXT 7125
cos
4053

PAGE 148-1
COUNCK 1363
COUNTR 1236
CPLOOP 3233
CR
6432
CREAD 3665
CRETN 3456
CRFUNC 0765
CRLF
0153
CRLFR 2346
CRAEP 1360
CSFN
2001
C S M O V E 4Q51
CSTA
4070
C S T A C 4071
C l l N L 7400
C13
4531
4320
c20
C2000 6 6 7 0
e2400 6 6 7 1
c3
4070
c4
4047
C770
6676
C7760 6675
DA
2302
DADP
0060
D A T A B A 3675
D A T C O M 3613
OAT€
3600
D A T T A B 4525
DAY
3742
OAYTBL 4564
OBAO
6115
O B A D l 5534
OBAOlP 6 1 7 s
DCNT
5139
DCNTP 4726
DCOS
7520
OCOSP 6665
DE
3366
DECNV 5 2 1 3
DECON 5 2 1 4
DECONV 5207
D E C O N l 5335
DEVCAL 0 1 2 4
DEVNAL 4317
D E V N A l 4030
OEVNAZ 4 0 3 1
DGTYP 5 0 7 6
OGTYPP 4725
D I G O U T 0400
OIGl
4125
D I G l A 3571
DIG2
4126
DIG3
4127
0164
4130

/OS/8

INDUSTRIAL B A S I C R U N T I M E

DIG5
9131
D I S I N 3630
Q I S M I S 0141
D I S P C H 7523
D I V B Y 0217
D I V I O 012s
DLCDF 2303
D C C D F L 1164
DLPTR 0Cl16
OLREAP 2275
DLRELK 7554
OLSTOP 0027
O C S T R T 0030
DNA1
3621
DNA2
3622
DNUMBR 53@5
DO
4045
R O A O D 6023
DONA
6027
DONE
3765
OONEF 5 9 6 6
BOlrlHK 6 4 6 6
OR
1867
D R l r R G l 0547
RRARG2 05SB
ORARG3 0 5 5 1
ORCALL 8532
DRERR 3365
DRERRP 0555
D R I V R L 4046
D R I V R N 4200
QS
441 1
O S W I T 0052
DT1
5101
DV
6355
OVLPl 5711
OVLl
5514
DVOPS 6315
DVOPSP 5533
D V O P l 6336
OVOP2 5 5 3 5
m m p w 6333
DVOVR 5777
O V T R A P 3514
DV 1
5765
OV2
5755
DV24
5795
DV24P 5532
D V Z Y P T 5136
EAE
0IQQ0
EATONE 6 4 1 4

EBC
EBLK
EDBLK
EDON

2730
3737
3746
S2h0

tF
3367
kFRTAL 4261
EFLG
8056
ELQP
7053
EM
3615
EMDQNE 3606
EMOQNL 3570
EMESS 41113
EMLOOP 3545
EN
4274
ENTLQK 4262
ENTNO 0162
ENTRYN 4032
ENVAL 3516
EOFSEL 0143
E O F S E T 2236
EOSPA 6677
ERROIS 1457
ERRET 4050
ERROR 01!6
ERRORR 4002
ESHFT 0435
W R A4134
E S T R N G 4112
ETA8
4137
ETABA 4135
ETLOP 4033
EXP
0044
EXPA0 4422
EX PA^ 4417
E X P B 1 4414
EXPON 3477
EXPONK 3630
E X P O N ~4120
EXPP
0040
E20P10 1307
FACCLR 0362
FACR
6031
FACREL 0133
FACHES 2370
F A C S A L 0132
FACSAV 3 3 6 1
FAUOL 4860
FAoDLK 3473
FAQDLL 5312
FAODM 4360
F A O ~ 6004
F A T A L 6771
FATCCHK 4040
FB
4012
FBITGT 6547
F R I T S 0117
FC
3443
FCLR
8137
FCNT
527s

FD
5527
FOOQN 5742
FBDONP 5 5 3 1
FOIVL 4062
FDIVM 4 3 6 1
F O I V l L 4067
F D I V l M 9362
FDVPT 5 3 1 1
FDl
5504
FDlP
5721
FERRLP 4 0 1 1
0037
FF
FFAOO 6 0 0 0
FFADP 4733
F F A T N 4200
FFCOS 4053
FFOIV 5722
F F O I V l 5412
FFDP
5446
FFDVP 4734
FFOl
5726
FFEXP 4120
FFE%PL 3625
FFGET 6 2 4 1
FFIN
5200
FFINLK 3476
F F I N l 5232
FFIX
4500
FFLOAT 4533
FFLOG 4263
FFLOGL 3626
FFMPP 4735
FFMPY 5600
FFMT
4613
FFNEG 6135
FFNEGA 5410
FFNEGK 5502
FFNEGP 5303
FFNEGR 5773
FFNGP 4736
FFNOR 6215
FFNORR 6236
FFORMT 1302
FFOUT 4600
FFPUT 6256
FFPUTP 0135
FFSIN 4000
FFSQ
6347
FFSUB 6117
F F S U S l 5400
FGETL 0134
FGETM 0134
FI
2273
FIDLE 0 1 2 3
FIDVP 3 6 3 1

FIG02

5241
FILEFA 6375
F I L E 1 6714
FILE2 6731
FILSTR 3 3 1 1
FILSTU 4306
FISUBL 4372
FXXDNE 4525
FXXL
4066
F I X L P 4515
FJOCI 0400
FLDW
0057
PLEN
4273
FLING 5142
FLINK 4722
FLN
3637
FLOAT 0562
FLOAT6 3420
FLQATL 3645
FLQATM 4356
FLOOK 4236
FLUSH 6425
FM
1624
FMPVL 3572
FMPYLK 4 0 6 1
FMPYLL 5310
FMPYLY 3627
FMPYM 4357
FN
2005
FNAP
3441
FNDMCY 0317
F N E G I 1226
FNEGL 0140
FNLP
6334
FNOM
4271
FNORL 0 1 3 6
FNORP 6176
FO
1637
FOTYPE 2355
FOUTl 4625
FOUT2 4634
FOUT3 4674
POUT4 4667
FPPARG 7246
FPPPNT 0035
FPPTMl 1164
FPPTMZ 1 1 6 1
FPPTM3 1156
FPPTM4 1153
FPPTMS 1150
FPPWRK 7 2 5 1
FPUTL 0135
FPUTLL 0720
FPUTM 0135
FRACT 48)71

/OS/8

INOUSTRIAL

FRANDP 2 3 4 1
F R O O T 3646
FSORL 4065
FSQRM 4365
FSTOP 370pJ
FSTOPI 05S7
FSTOPN 0 5 5 6
FSTOPP 0560
FSTOPl 0 1 6 1
FSUBL 4064
FSUBLL 3573
FSUBM 4363
FSUBlL 4@63
FSUBlM 4364
F S W I T C 2050
F T C O M 2424
FTiFLG 4 5 3 1
FTRPRT 4S0S
FtYb
3015
FTYPE 4555
FTYPL 0150
FTYPSE 3462
FUBXXX 1406
F U D X X l 1416
FURXX2 1405
FUJUMP 1523
F U N C l I 1467
FUNCZI 1466
FUNC3I 1 5 3 5
FUNC41 1550
FUNCSI 1465
F1116 0 0 1 6
F I X 1 7 0017
FlSAV 0020
FlSAV2 0 0 2 1
F l S A V 3 0022
FlTMPl 0023
FlTMP2 0024
FlTMP3 0025
FlTMP4 0026
G A I N S 0353
GC
7274
GCHR
5322
GCSE
1153
G C S € 1 1157
GCcl3
7307
GD
5025
GE
0045
GENERR 8853
GETCH 3225
GETCHG 3 5 0 1
GETCHL 01U2
GETE
5250
GKNT
5003
GON
3761

B A S I C RUNfIME
GOSUB

0415
GOTSPT 1036
GR
0470
GS
0417
GSP
0447
G S P O T 0003
G S T C K 2314
GTFLG 42B0
GTlFLG 4263
WAhlGlld 7565
HGhCLK 7115
HGHTME 7 1 1 3
HOOKL, 3776
HdRO
0045
HORDP 0 0 3 6
I A
1464
IC
0056
IDbE
2270
IF
4424

a070
3534
ILOOP Q 2 1 2
ILOOPF 0 2 3 4
ILOOPL 8 1 1 3
ILOOP2 0214
XN
4033
INALQG 0277
INBFP BIB07
XNITFN 6427
INPHK 6521
I N P f C L 3477
XNPUT 5347
INSAV
0065
I N S A V P 06134
INSC
3413
INT
3400
I N T E R 5 1141
XNTL
0114
I N f P C 0035
I N T P O S 3420
I N T R E T 6764
IOTA6 2 @ 3 1
IQUT
5360
ISZAC2 6310
I S Z F G T 5275
IS2BIG 0065
I V
Om60
I V G A I N 0@67
Z l L N L 7410
JEOFI 0450
J F A I L 0413
JFOR
2034
JMPFIL 1446
JMP1
0245
J M P I S A 0734

IGS

J M P I S N 4012
J M P 1 2 0744
JMP13 1205
JMP16
1604
JMPUSR 1557
JMS1
0244
JWSIU
1417
JMS15 1 4 3 2
JMS17 1540
JMSSI 0303
JMSTAO 1531
JNEG
3466
JSL
2627
JUSNEG 3464
KC
3751
KC240 1140
KEX
3547
KFOl
5447
KKK240 3573
KKMl0 3704
KKMl2 5775
KK12
5313
KK13
4333
K42000 4067
KK40
3265
KK7
4730
KK7600 1253
KL7600 3744
KM€
5306
KWl2
5135
KM13
5776
K M 1 4 4 5134
KM15
3754
KM20
4932
KM22
3777
UM4
0004
KM40
0105
UP7
4732
KNT
4737
KNTP
5154
KSKP
4110
KSKP2 4000
KUPARO 3750
UYBRD 7201
K0
4412
KO001 3464
K0a07C 3703
K O O 1 O 0073
K0014 0074
K0037 0740
K0Q37C 3677
K0Q57 3 7 0 1
K0077 0075
K0l0lrl 81676
K0200 06377

K0210 3205
K0300 4057
K0340 0 1 0 0
K0377 0 1 0 1
K1400 4313
Kl6
4721
K20
3266
K200
0077
K2000 4314
K215
0054
K232
3461
K240
3204
K26B
4056
42700 3 7 0 0
K300
6711
K4207K 4350
K5700 3702
K6
4740
K6000 3 7 7 2
K6213K 4 3 5 1
K6222 4572
K6223 4510
473
4564
K7400 0 1 Q 2
K7477 0 1 0 4
K7506 5 3 4 6
K7554 0 4 3 6
K7577K 43S2
K7600 0437
K7607K 3677
K7700 0 1 0 3
K7760 3662
K7773K 4353
L A S T B 3325
LDH
0131
LOHC
2075
LOYCDL 4504
LOHOF 2647
L D H I N I 2676
LOHINL 0127
LDHL
2646
LDHPR 4 5 0 1
LOHPST 2133
LDHPSW 4502
LDHR
2705
LDHSST 0157
LDHSWT 2704
LEN
3414
LEV
5477
LF
6452

LINEHI 0046

L I N E 1 1113
L I N E 1 1 1127
LINELO 0067
LK7607 3745

/OS/8 INDUSTRIAL B A S I C RUNTIME
LM
LMAKE

6360
4@60
LMAKEL 3566
LNE
0524
LNEFUC 7167
LNKSVE 6747
LNSET 1075
LN2
447 1
LNZOV2 4411
LOADOF 3163
LOG
4263
L O G C l 4455
LOGC3 4460
LOCCS 4463
LOGt?€ 44B6
LOQP
5052
LOP01 3 7 2 2
LOP02 3746
LQPl
6875
LOP2
be37
LORD
8046
LllRRP 0037
LOWCLK 7116
LOWTME 7114
LPY
1026
LROl
7361
LRESET 2165
LRSCOM 2 6 5 5
L S U B l I 1404
L S U B Z I 1Y13
LSlI
1401
LS2I
14BB
LTRPRT 4302
L7466 3676
L7600K 4355
L7605K 3664
L7Q0SP 4356
L7607
1527
C7620 3 6 6 1
L 7 6 2 1 3663
47642 US71
L7644 3660
L 7 7 2 1 4573
L7727 4574
L7746 0354
MAKE0 4052
M A S K I 0031
MASKL 3427
MATCHL 1126
MCC
3747
MCDFl

6667

MCNTLC 7220
MCOCQN 4400
MCRMAL 3456
MCSPE 44B1

M C T H L Z 3103
YONE
3226
MDONE 5627
MQSET 5450
MDSETK 5774
MDSETP 5445
MRV
s31i17
MD 1
5452
MDlP
5443
MFATAL 4136
M I N U S 5363

MIhUSP 3460
MINUS3 0355
MIN4
4354
MKbl
2727
MML
4501
MMM4
4415
MM260 3572
MNXTE 7112
M N I T E P 3757
MNTHCK 3760
MOOEBK 0064
MODESM B063
MONTH 3755
MPLP
5653
M P L P l 5654
MPLPZ 5666
MPY
2244
MPVLNK 0 1 2 1
MPlEL 5 7 0 1
MP12LP 2 2 5 1
MP24
5643
M1
4727
MlR
3470
M13
453B
MI4
@la6
M215
0055
M240
5361
M6
4413
N A M E G 4416
NAMEGL 4050
NCG
4450
NCGS
4464
NCHK
4113
NCHKL 4262
NEMCDF 6 3 0 1
NEWTAG 7330
NEXRCK 4260
NEXREC 3275
NEYREL 0152
NFL4G
412@
NFLGST 4111
NGT
4257
NHNDLE 4103
NHNDLL 4261

PALB-VJ

9/20/73

3724
NOCZ
3420
NOP1
6111
NOP2
6053
NORMLP 6225
NOTE
4743
NULLS7 4370
NUM
4113
N X T A R G 7233
N1
4403
NlA
4542
N2
4404
N3
4U05
N3A
4402
4406
NS4
4407
N6
4410
N6A
4543
N7666 3 6 1 1
O A C H R 6455
OADB
6157
OPDDP 5 1 4 1
O A T A D I 1526
OCDF
2136
OE
1512
OLP
7015
ONE
3474
OhlEHAF 4466
ONERET 4472
ONE1
4475
OPENAF 4001
OPENAV 4000
OPEhlNF 4004
OPENNV Y003
OPERII
1200
OPH
0050
OPL
0051
OPNEG 6146
OPNEGP 5502
OPSR
6034
OPX
0047
O T R A P A 4532
OUT
5144
OUTDG 5150
OUT'OGP 4720
OVADD 1 5 1 1
OVDNE
1516
OVERLA 3400
OVML
0343
OVRLAY 1530
00
6354
PA
4415
P A C K C H 2735
PACKL 0145
PATCHF 5364
NOCTC

PAGE 148n4
PATCHP 0155
PDNE
3216
PDP
5001
PHYCHN 0027
PINFO 0 3 5 6
PIOV2 4403
PLUS
5362
PNT
1763
POLYNL 4304
POLYSN 4026
POS
44QQ
P O S I T N 4500
POSSET 4424
P O V T A B 0357
POWER 3472
PR
5016
PROCP 4776
PRDCPP 5143
PRES7 3542
PRNTX 5160
PRNTXP 4723
P R N T X l 5164
P R Z R O 5172
PRZROP 4724
PS
5023
PSFLAG 0 0 3 1
PSSTRT 0026
PSWAP
1230
PSWAP;! 4 3 2 1
PSWP2P 4544
PSlL
0360
PSZL
0361
PTR
7061
PTRBMP 2156
PTR1
0033
PUSKP 0 4 1 1
PUTCH 5247
PUTCHL 0112
PWFECH 0200
PWFECL 0120
PWRFLD 7574
PWRJMP 0107
PWRNAM 3552
PWRUP 011@
PZR
5015
PlCDF 1240
P l C D F l 1245
P l S W A P 0256
P2CDF 1243
P2CDFL 4566
P 2 C O F l 1247
P2CDLl 4567
P2SWAL 3743
P200
5211
QUAD2 4017

/OS/8

XNDUSTRIAL B A S I C R U N T I M E

QUA03

4022

QUAD4

4a24
0042

QW
R D I G I N 0453
ROIGOU US01
R O I T B C 0600
R D L I S T 7545
ROOTRL Id640
R f
3Cal0
READFL 300Q
R E A D F W 3145
R E A 0 1 3105
READ17 0735
RELUSR 4 2 6 1
REPOWR 7555
R E S D L S 2552
R E S T 1 1650
R E S T O R 2555
RETMOL 3674
RETMOO 3521
R E T R N I 0456
RETRNO 3S71
R E T R N l 3610
RET@
35h5
R I G H T L 2665
RIGHTS 2633
R I P T R 2455
RND
4544
RQ
6437
RONLY
3307
RQ6
0251
RSEEO 23U5
RSEEDC 4563
RTN2
5371
R T Z R O 5620
RWONC 3305
SAC
0316
SACCMK 2122
SACEM 2216
SACL
3421
SACPTR 0111
SACUBC 2106
SA#
0733
S A F I N D 1745
SARRAY 0 7 2 2
SASTHT 0 0 2 4

2232

SCALDF 0314
SCALOL 1145
$CASE
0241
SCDF
1735
SCOMP 2051
SCBNTU 4462
SCQNl 22881
S C S T R T BIB21

SOIS
B273
SDQTBL 41610
SE
4706
SEG
427 1
SEGCML 4373
S E G C O M 2222
S€P
5157
SEPl
0256
SETF
2044
SETTTY 6532
SETUP
1343
SEI
4707
SFN
2@@0
S F N L P 2023
SG
0054
SGN
3632
SHfTNO Of412
SHLFT 5635
S I G N F 5300
SIN
4000
SINAl
4367
S I h i A 3 4372
S I N A S 4375
SINA7 440B
SI“
0521
$LOAD 3146
SLOOP 3713
SLOVER 2 5 4 1
S L R C O M 261U
SMODE 0 2 6 6
SNGQ
2117
S N E Q l 2116
SPFUNC l b @ B
S P l N N R 0017
SWHPS 4452
SR
3127
SRCLP 4445
SREAR 2416
SRESET 0 3 7 0
S R F I N 2447
S R L I S T 24BQ
SRLQOP 2 4 1 1
SSAO
4555
wasp 0510
SSLP
3156
SSMODE 2307
SSTEX 0 5 2 3
S S T O R E 41U73
ST
2444
STAENT 0465
START8 4272
START3 1 1 4 1
S T A R T 4 66062
STATE 0551
St8
3636

PPL8*V7

9/20/43

STCGTJ 3500
STCOM
STCU0C
STDF
STOFL
STFILK
STFINO

1676
2124
1677
1163
0741
1664
S T F I N K 4503
S T F I N L 0302
STH
0130
STHDF 2603
STHDKK 0374
S T H I N I 2636
S T H I N L 0126
STHL
2600
STHR
2645
S T H R S T 016Q
STHSWT 2644
STOPEM 1107
STOP1 4051
STOR
6750
STPCNT 12U6
STPTMR 1161
STR
3422
STRCNT 0071
STRLEN 01132
S T R M A X 0070
STRNGA 6374
STRPTW 0072
S T S L P 3U40
STSTRT 0023
SU
0623
SUB0
6125
SU60P 5 4 1 1
SUCJMP 0 4 2 6
SUPFUB 6400
sw
3256
SWCCP 2477
SWITCC 0 0 4 2
SWITl 0 0 5 4
SWIT2 0055
SWRITE 2460
s1
0033
S l P R A Y 6527
s2
0834
SZPRAY 6530
TAB
1753
TABLE 0226
TADTAB 1 5 3 2
T A G I T 0750
TAGITP 0352
T 8 L D Y P 3767
TBLSCN 0 2 3 3
TCLFLG 6 7 6 0
TDFIXL 4347

PAGE 1 4 8 r S

101
0476
TOOPfl 1 5 0 3
TDOFF2 0 5 4 3
TOONE 3553
TDSRCH 7 1 4 1
TO8Pl 6 6 7 2
TD8PZ 6673
TE
0066
TEMP1 0 0 4 0
TEMP10 0 0 6 1
TEMP11 0 0 6 2
TEMP17 3 0 2 3
TEMP18 3 0 1 6
TEMP2 0 0 0 6
TEMP21 2636
TEMP24 0 5 2 5
TEMP3 0 0 4 2
TEMP4 0 0 4 3
TEMP5 0047
TEMP6 00S0
TEMP7 0 8 5 1
TEN
5317
TICKS 0364
TIME
0677
T I M E R 1000
TIMEX
1105

T I M I N T 7117
1109
7121
0043
6353
7060
7055
7011
T M R T M l 7056
TMRTM2 7057
TM3
5155
TM3Pf 5304
TO
0064
TOOBIG 0256
TOBMNY 0063
TOUT
3272
T O V P I 4160
T O Z B I G 0042
TP
5314
T P R I N T 3524
TP1
5319
TRACE 3 7 7 0
TRHOOK / 1 3 4
TRPRET 1 0 6 5
TRREST 3775
TRYCLS 3 5 2 6
TSMET 7052
T S T T T Y 1042
T T C H C T 1032
TZNeNT
TINCNZ
TM
TMPY
TMRCNT
TMREND
TMRSCN

/OS/8

INDUSTRIAL B A S I C

TTESf2 4QQl
TTFULP 10@3
TTGET 3 1 4 1
T T G E T P 1031
T T M O R E lF855
T T P U T P 1030
TTYBUF 6600
T T V C H K 1Q3U
T T Y C H X 3565
TTYENO 6677
TTYF
6712
T T Y I N B 6600
T T Y S I Z 1033
T T Y T C F 1053
TTYUSR 4111
Tin
7063
TlHR
7073
T1L
7062
T l L N H 7103
T l L N C 71B2
TlLR
7072
T2H
7065
12HR
7075
TZL
7064
T2LNH 71@5
T2LNL 7104
TZLR
7Q74
13H
7067
73HR
7077
T3L
7066
T 3 L N H 7107
T3LNL 7106
T3LR
787b
TYH
78171
TUHR
71Q1
TUL
7070
T4LNH 7111
TULNL 71112
f4LR
7180
UDCBAO 0850
UPCHNL 01@7
UDCI
7254
URCM3 6664
UOCTAG 7257
U R C T M l 7362
UDCTM2 7363
UDCWRK 7366
UDDI
6365
UDEI
6364
UOCA
6363
UDLB
6367

UDSC
UQSF
UDSS
UNPACK
UNSFXX
UNSLP

RUNTIME

PAL8mV7

9/20/73

6353

)IDRITE
XFLOAT
XIT
XLCOM
XPUT
XPUTCH
XR0
XRl
XR2
XR3
XR4
XRS
XXllS
XX212
xx4
X7607
YEAR

4522
4505
0456
4514
0122
1000
0010
QQll
0012
0013
0014
0015
2340
2313
2312
1235
3756
1513

5361

6351

3u47
1615
1642
UNSOUT 1646
UP
0134
UPDATE 37415
UPDAY1 3715
UPDAYZ 3720
UPLVL 6SU2
USE
2562
USECON 0005
USELOG 3613
USELOL 3 5 6 7
USH
0077
USHCAL 4072
USHCP 3470
USHERR 6763
USRREL 4183
USRRP 3 4 7 1
U123C 3056
VAL
346h
VALCNT 3422
VALGET 3502
VALLK 0154
VALUE 0057
VR
3063
WOONE
3245
WE
3032
WHO
7535
W I D T H 0534
WQHDr4 0163
W Q R D l 0172
WORD10 8165
W O R D 1 1 0166
WQR012 8147
UDPD13 @ I 7 0
W O R D 1 4 0171
WORD2 El173
#OR03 8174
wQR04 0175
WORDS 0176
wQRR6 El177
WORD7 0164
MRaLK
3342
W R e L K K 3463
WROA
3112
W R I T E 1 3200
W R l T F L 3023

UDLS

6357

WRJTFW 6225

UORA
UDRD
UDRS

6356
6366
6355

W0YTR 3466
WQPTRA 3465
X O G E T 45@6

ZAPION
ZCNT
ZNP
ZMINY
ZR
ZRCONT
ZRQFF
ZRORET
Z2tZ

3773
6341
4334
1342
1352
1334
4470
7357

PAGE 148-6

INDEX

Absolute value function ABS (X),
6-5
ABSVAL subroutine, 11-18
Alphanumeric information, 7-1
Analog input (ANI) function, 8-5
Analog output (ANO) function, 8-5
Angle brackets ( < > I , 7-3
Arctan function - ATN(X1 , 6-7
ARGPRE subroutine, 11-14
Arguments passed to user function,
11-8
Arithmetic, 2-1
exponentiation, 2-5
functions, 6-2
numbers, 2-1
operations, 2-2
overlay, 11-26
parentheses, 2-3
priority of operations, 2-3
relational operators, 2-4
variables, 2-2
Array location, 11-20
Arrays, 5-3
Array symbol table, 11-7
ASC function, 7-5
ASCII conversion table, D-1
ASCII files, 10-1
ASR-33 Teletype, 1-3
Assembling the sources, E-1
Assembly language functions, 11-1
example , 11-27
Assembiy language/INBRTS interface,
11/23
Assignment statement, 3-4

Constants, 7-1
CONTACT statement, 8-3
Control commands, 1-7, 9-1, A-5
Control statements, 3-13
Conventions for alphanumeric
strings, 7-1
Conversion
ASCII/decimal number, 7-5
string/number, 7-6
Core layout, INBRTS, 11-2
Core usage, Field 1, 11-18
Correcting the program, 1-4, 9-1
Cosine function -COS (X), 6-6
Count (CNT) function, 8-7
Counter input (CN1) function, 8-6
Counter output (CNO) function, 8-6
COUNTER statement, 8-2
CTRL/ characters, 1-2
Data formats, 11-4
DATA list, in core, 11-6
DATA statement, 3-11
DAT$ function, 7-7
Debugging function
TRC(X) , 6-9
Decimal formats, 2-1
DECwriter, 1-2
Definition of OS/8 Industrial
BASIC, 1-1
DEF statement, 6-8
Deletion
of character, 1-3, 9-1
of line, 9-1
of statement, 1-4
Delimiters, 10-4
Device driver space, INBRTS, 11-22
Devices, resident, 10-1
Diagnostics,
compile time, B-1
run time, C-1
Dimension (DIM) statement, 5-2
Dimensioning strings, 7-1
DISMISS statement, 8-3
DLREAD subroutine, 11-17
Documentation conventions, 1-2

Backslash ( \ ) , 3-3
BSW subroutine, 11-17
Buffer space, 11-22
BYE command, 9-8
Carriage return ( 3 , 1-2
Chaining, 10-1
CHAIN statement, 10-6
Character deletion, 1-3, 9-1
Characters
ASCII, D-1
format control, 3-7
CHR$ function, 7-5
Clock (CLK) function, 8-4
CLOSE# statement, 10-5
Commands, 1-6
control, 1-7, 9-1, A-5
edit, 1-7, 9-1
Comments, 3-3
Compiler , 1-6
Compile time diagnostics, B-1
Concatenation of strings, 7-4
Considerations in assembly, 11-25

Editing commands, 1-7, 9-1
Editor, 1-6
End-of-file detection, 10-6
END statement, 3-4
Entering new program, 1-3
Equals (=) sign usage, 2-2
in IF-THEN statement, 7-3
Errors, typing, 1-3, 1-41 9-1
E-type notation, 2-1
Example program,

1-5, 3-1

assembly language function, 11-27
control program, 8-7
Exclamation mark ( 1 ) usage, 3-5
x-1

Executing the program, 1-4
Exponential format, 2-1
Exponential function - EXP(X),
Exponentiation, 2-5
Extended I/O functions, 8-3

Interrupting program execution, 1-4
Interrupt skip chain, 11-28
I/O table, INBRTS, 11-22

6-7

Keyboard monitor,

FAC
see Floating point accumulator
Features of OS/8 Industrial BASIC,
1-1

File formats, INBRTS, 11-21
File overlay, 11-26
FILE# statement, 10-2
Files, 10-1
Fixed length files, 10-1
Floating point accumulator (FAC),
11-10
Floating Point Package, 11-10
Floating point routines, 11-11
FNA(X) function, 6-8
FOR statement, 4-1
Format control characters, 3-7
Functions, 6-1, A-6
arithmetic, 6-2
debugging, 6-9
extended input/output, 8-3
industrial, A-7
input/output, 3-5
transcendental, 6-6
user-defined, 6-8

1-3

Leaving the computer, 1-5
LEN function, 7-4
LET statement, 3-4, 7-3
Line deletion, 9-1
Line (LNE) function, 8-6
Line numbers resequenced, 9-2
Linking into the interrupt skip
chain, 11-28
LIST command, 9-5
LISTNH command, 9-5
Lists, 5-1
Loader, 1-6
Loading OS/8 Industrial BASIC, 1-2
Logarithm function, 6-7
LOOPS, 4-1
nesting, 4-2
Mainline mode, 1-8
Matrices, 5-1
Messages, diagnostic, B-1, C - 1
MPY subroutine, 11-17
Multiple statements, 3-3
Multiply routine, 12-by-11 binary,
11-17

Generation of system, F-1
GOSUB statement, 6-11
GOT0 statement, 3-13
Hardware requirements, 1-1
Hints for assembly, 11-25
IF END# statement, 10-6
IF-GOT0 statement, 3-14
IF-THEN statement, 3-14, 7-3
INBRTS/assembly language interface,
11-23
INBRTS
core layout, 11-2
file formats, 11-21
input/output, 11-21
Input of string data, 7-1
Input/output statements and
functions, 3-5
INPUT statement, 3-5, 3-8
INPUT# statement, 10-4
Inserting statement, 1-4
Interfacing assembly language to
INBRTS, 11-23
Interfacing Field 1 and Field 0,
11-19
Integer formats, 2-1
Integer function - INT(X). 6-5

NAME command, 9-7
Names of files, 10-1
Natural Logarithm function - LOG(X),
6-7
Nested loops, 4-2
Nested subroutines, 6-12
NEW command, 9-6
NEXT statement, 4-1
Numbers
arithmetic, 2-1
printing format for, 3-8
resequenced line, 9-2
statement, 3-2
Numeric files, 10-1
OLD command,

9-6

Operations
arithmetic, 2-2
relational, 2-4
Overlays, 1-6, 11-26
INBRTS, 11-3
Page 0 usage, 11-27
Parentheses usage, 2-3
Passing arguments to the user
function, 11-8

x-2

PNT function, 3-10
POS function, 7-6
Power fail - restart, 8-9
PRINT statement, 3-6
PRINT# statement, 10-3
PRINT statement used with INPUT
statement, 3-8
Print zones, 3-7
Priority of arithmetic operations,2-3
Program
correction, 1-4, 9-1
entry, 1-3
example, 1-5, 3-1, 8-7 11-27
execution, 1-4
interruption, 1-4
loading and running, 1-2
subroutine, 11-15
termination statements, 3-4
Question mark (?) usage, 3-5
in string data, 7-2
RANDOMIZE statement, 6-4
Random number function - RND(X) , 6-2
Read digital input (RDI) function,
8-5
Read digital output (RDO) function,
8-5
READ statement, 3-11
Real time operations, 8-1
example, 807
extended functions, 8-3
power fail restart, 809
statements, 8-1
UPIR identification functions, 8-6
Relational operators, 2-4
in IF-THEN statement, 7-3
REMARK statement, 3-3
RESEQ program, 9-2
Resident devices, 10-1
Restart after power fail, 8-9
RESTORE statement, 3-12
RESTORE # statement, 10-5
RETURN statement, 6-11
Routines
floating point, 11-14
unusable by Assembly Language
functions, 11-25
RUBOUT, 1-3, 9-1
RUN and RUNNH commands, 9-8
Running OS/8 Industrial BASIC, 1-2
Runtime diagnostics, C-1
Runtime system, 11-2
Runtime system overlays, 1-6

SAC
see String Accumulator
SAVE command, 9-7
Scalar table,

SHIFT/ characters, 1-2
SHIFT/L, 3-3
SHIFT/O, 1-3, 9-1
Sign function - SGN(X) , 6-4
Sine function - SIN(X) , 6-6
Spaces, blank, 1-2
Spaces
in programs, 3-2
in statements, 2-4
Square root function - SQR(X), 6-6
Statement deletion or insertion,l-4
Statement numbers, 3-2
Statements, 1-6, 3-1
control, 3-13
elementary OS/8 BASIC, A-1
file, 10-1, A-4
input/output, 3-5
program termination, 3-4
real time, 8-1
State (STA) function, 8-7
STFIND subroutine, 11-16
Stop execution, 1-4
STOP statement, 3-4
STR$ function, 7-6
String accumulator (SAC), 11-7
String array table, 11-9
String concatenation, 7-4
String handling functions, 7-4
String overlay, 11-26
Strings, 7-1, 11-5
String symbol table, 11-8
String to number conversion, 7-6
String variable or array,
locating a, 11-16
Subroutines, 6-1
GOSUB statement, 6-11
INBRTS, 11-11
nesting, 6-12
RETURN statement, 6-11
Subscripted variables, 5-1
Symbols used in manual, 1-2
Symbol tables, H-1
INBRTS, 11-4, 11-7
System build instructions, E-1
System components, 11-1
System generation, F-1
System performance, G-1
TAB function, 3-10
Tables, data, 5-1
Teletypes, 1-2
Terminal I/O, 11-21
Terminals, 1-2
Termination of program, 3-4
TIMER statement, 8-1
Transcendental functions, 6-6
TRC (X) debugging function, 6-9
Typing errors, 1-3, 1-4, 9-1

11-7, 11-14

UDEF function call, 6-8
Underlining, 1-2
UNSFIX subroutine, 11-16

SCRATCH command, 9-5
SEG$ function, 7-7
Send digital output (SDO) function,
8-5

x-3

Unusable r o u t i n e s , 11-25
UPIR
see U s e r Process I n t e r r u p t
Service Routine
USE s t a t e m e n t ,
6-8, 11-20
User p r o c e s s i n t e r r u p t mode, 1-8
U s e r Process I n t e r r u p t Service
Routine ( U P I R ) , 8-1
i d e n t i f i c a t i o n f u n c t i o n s , 8-6
Using OS/8
11-27

VAL f u n c t i o n , 7-6
Variable l e n g t h f i l e s ,

10-1

Variables, 2-2, 7-1
s t o r a g e o f , 11-4
s u b s c r i p t e d , 5-1
XPUTCH s u b r o u t i n e ,

11-15

Zero s u b s c r i p t , 5-2
Zeroes, s u p p r e s s i o n o f l e a d i n g /
t r a i l i n g , 2-1

x-4

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OS/8 Industrial BASIC
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