Digital PDFs

DIGITAL-7-10-O

January 1965

8 pages

Original

0.2MB

Document:	TTYoutputPkg
Order Number:	DIGITAL-7-10-O
Revision:
Pages:	8
Original Filename:	http://bitsavers.org/pdf/dec/pdp7/DIGITAL-7-10-O_TTYoutputPkg.pdf

OCR Text

1•

IDENTIFICATION

1.2

Oigital-7-10-0

1.3

Teietype Output Package

1.3

January 7 I 1965

FDF

LIBRARY

Digital-7-10- 0
Page 2

ABSTRACT

This package includes subroutines which allow the user to type characters on
Iine represented by 1, 3, or a string of codes. Routines are included to facil itate formating
by the user. The user must supply his own subroutine, OTV, to type out one Teletype character.
3.

REQUIREMENTS

3.3

Equ ipment
Teleprinter

USAGE

4. 1

The Teletype Output Package source tape should be assembled with the program
which refers to it, orassembledusinsa symbol punch which contains the required subroutine calls
{see Digital-7-3-S}. In either case, the operation of the routines are independent of their
position in memory. The user must supply a type-out routine, OTV, which is referred to by
the package {see be Iow} .
4.2

Ca II ing Sequence
The following call ing sequences may be used to call the Teletype output sub-

routines.
Format Routines
TCR

Type a carriage return and Iine feed.

TSP

Type a space.

TVT
Type a tab. Tab stops are located every TTAB spaces. This
value is initially 10, but may be altered by the user. The subroutine counts the number of
characters being printed on a Iine so that a TVT call will generate the proper number of spaces
for a consistant format. TCR resets the character count to

TIN
Initialize the teleprinter. Type a carriage return, line feed,
lower case, and set the character count to O. TIN should be called before any other subroutines in the package.
Character Type-out Routines
TDIGIT

Type the digit (code value from 0 to 9) in the right four bits of

the AC.

FDP

LI BRARY

Digital-7-1 0- 0
Page 3
TY1

Type the character represented by the code in the right six bits

of the AC.
TY3
Type the three characters represented by the codes in left, middle,
and right six bits of the AC, respectively.
~WA

TSR

Type the string of characters represented by the codes stored beginning in register A. A code having zeros in the leftmost five bits terminates the string.

All characters are typed by call ing the subroutine OTY, which must be defined
by the user. Two sequences are suggested, one for use with programs which use program interrupt for I/O service, and one for programs which do not.
NOTE: When using a Type 28 Teletype, TLS will type characters
represented by 5-bit codes; when using a Type 33 Teletype, TLS
will type from a-bit codes.
The following subroutine works very well with interrupt programs where buffering
is not needed:
OTY,

o
TLS

JMP! OTY

TYINT,

TCF
ISZ 0
DISMISS

When using the associated program interrupt routine, an interrupt from the
teleprinter should execute the command:
JMP TYINT
In addition, the symbol DISMIS should be defined as a JMP to the section of
the interrupt routine which restores the AC and link and dismisses the program interrupt.
The following subroutine is suggested for non interrupt programs:
OTY

o
TLS

TSF
JMP .-1
JMP I OTY

Digital-7-10-0
Page 4

DESCRIPTION

6. 1

Discussion

Th~se routines assume that the codes which represent the characters to be typed
consist of six bits. The leftmost five bits are the Baudot code for the character; the rightmost
bit indicates the case of the character (1 for upper case, 0 for lower case). This format is
generated by the PDP-7 Assember's character input operations in Teletype mode (see
Digital-7-3-S). The case of the Type 28 Teletype is automatically checked (and adjusted if
necessary) when each character is typed. A code whose leftmost five bits are 0 is not printed.

When using a PDP-7 with KSR33 teleprinter, the 5-bit Teletype codes are translated to 8- bit Type 33 codes (ASCII plus 200) before printing. Case shifts on the KSR33 are
nonexistent. References to case in this document may be ignored when using the KSR33.
WARNING

When using a Type 28 Teletype the routine keeps track of keyboard
case and assumes it knows the case at all times. However, if the
L!ser is also using the keyboard for input, he may change the case
without the routines knowing it, possibly causing hash at the next
type-out. For this reason and also for convenience, it is suggested
that the user keep track of case by using the same indicators the
package uses.
The contents of the register OCS indicates the case of the teleprinter, 33 for upper case and 378 for lower case. If this is
8
changed wnenever a case shift is typed upon input, no problems
of this type will be encountered.
10.

PROGRAM

10.4

Program Listing

PDP-7 BTA

/TELETYPE OUTPUT PACKAGE 8-13-63
XIT=rAC-JMS TTAB~10
/TYPE 1 CHARACTER FROM AC BITS 12-17

PDP

LIBRARY

TYJ;:.JMS.

Digital-7-10-0
Page 5

DAC TY~SVAC
RAR
JMS TYlA
XIT TY1
TYEXIT
/TYPE 1 CHARACTER (5 BIT),
TY1A,
0
DAC T~EMY
AND (37
SNA
JMP TY2
703301
SKP
JMP TYlE

L:rnK JNDICATES

CASE

LAC OCL

SZL

LAC OCU
SAD OCS
JMP • 3
JMSOTY
DAC OCS
LAC TEMY

TY2,

JMSOTY
ISZ T.:,BC

LAC TEMY
JMP I TYlA

/TYPE 3 CHARACTERS FROM AC 0-5, 6-11,12-17 RESPECTIVELY
TY3::JMS •

DAC TYSVAC
JMS RIE
JMS TYIA
JMSRIE

JMS TY1A

JMS RIE
JMS TYlA

XIT TY3
TYEXIT
/TELETYPE OUTPACKAGE PAGE 2
/TYPE A CARRIAGE RETURN, AND LINE FEED
TCR=JMS •

DAC TYSVAC
703301
SKP
JMP TCRA
LAW 2
JMS OTY
PDP

LIBRARY,

Digital-7-10-0
Page 6

LAW 10
JMSOTY
DZMTBC
XIT TCR
TYEXIT
/TYPE A SPACE
TSP=JMS •

DAC TYSVAC
LAW 4
703301
SKP
LAW 240

JMSOTY'
ISZ TBC
XIT TSP
TYEXIT
/TYPE A TABULATION
TYT=JMS •

DAC TYSVAC
LAC TBC
ADD {I

(-TTAB
SMA
JMP .-2
TAD (-1
DAC TEMYI
LAC TYSVAC
TSP
ISZ TEMY1
JMP .-2
XIT TYT
TYEXIT
TAD

/TELETYPE OUTPUT PACKAGE - PAGE 3
/TYPEWRITER INITIALIZE
Trn=JMS •

DAC TYSVAC
LAC OCL
DAC OCS
703301
SKP

JMP • 3
TLS

L:BRARV

Digital-7-10-G>
Page 7

JMS OTY

LAC TYSVAC
TCR
JMP I TIN-JMS
ITYPE THE DIGIT IN THE AC
TDIGIT=JMS •

DAC TEMY1
AND (17
ADD (LAC NCT
DAC • 1
XX

TIl
LACTEMY1
JMP TDIGIT-JMS
ITYPE A STRIN G OF CHARACTERS
TSR~JMS

•

o
DAC T~EMY1
LAC I TEMY1

TY3

AND (76
ISZ TEMY1.
SZA
JMP TSR-t-2-JMS
LAC TENYl
JMP I 'rSR-JMS
/EXIT AFTER RES TORIN G AC AND LINK
TYEXIT JMP •
DAC TEMY
RAL
LAC TYSVAC
JMP I TEMY
/TELETYPE OUTPUT PACKAGE - PAGE 4
/ROTATE LEFT 6
RI.6,
0
RTL
RTL
RTL
JMP I RL6
/TABLE OF DIGITS
NeT,
33
73
63
/eASE STORAGE

oeu,
oeL,

ocs,

25
7

37
0

lEND OF TELETYPE OUTPUT PACKAGE
PDF

LIBRARY

/PDP-4/7 ADDENDUM
TYlB,
ADD (LAC BTATAB-l
DAC • 1
XX

DigitQI-7-1 D-CD
Page 8

SZL
TY ID,
TYIC,

TCRA,

JMP TYIC
JMS OTY
JMP TY2-1
JMS RID
RTL
RTL

JMPTYlD
LAW 215
JMS OT'!

LAW 212 .
JMP TCR-JMS 10

BTATAB,

START

265324

/5,T
215215
271317
240240
243310
254316
256315
212212
251314
264322
246307
270311
260320
272303
273326
263305
242332
244304
277302
211323
266331
241306
257330
255301
262327
2473.12
377377
267325
261321
250313
377377

/CARRIAGE RETURN

/9,0
/SPACE
/x,H
/, ,N

/. ,M
/LINE FEED
/),L

/4,R
/+,G
/8,1
/O,p

/:,C

/" V

/3,E
/$,Z

/"D

/?,B
/BELL,S
/6,y

/f,F
//,X
/-,A
/2,W
/~,J

/FIGURES

/7,U

/l,Q

/{,K
/LETTERS

FDP

LIBRARY