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PREFACE

The PDP-8 comes to the user complete with an extensive selection of system programs and
routines making the full data processing capability of the new computer immediately available
to

each user,

eliminating many commonly experienced initial programming delays.

The programs described in these abstracts come from two sources, past programming effort on
the PDP—S computer, and present and continuing programming effort on the PDP-S.

Thus the

PDP~8 programming system takes advantage of the many man-years of program development and

field testing by PDP-S users.

Although in many cases PDP—S programs originated as PDP-5 programs, all utility and Functional
program documentation is issued in a new, recursive format introduced with the PDP-8.

Programs written by users of either the PDP—S or the PDP—8 and submitted to the users‘ library

(DECUS
USBFS

Digital Equipment Corporation Users' Society) are immediately available to PDP—8

Consequently, users of either computer can take immediate advantage of the continuing program
developments for the other.

...

ill

CONTENTS

Chapter
INTRODUCTION

.............................................

OPERATING FEATURES

ooooooooooooooooooooooooooooooooooooooo

Modes at Operation

.......................................

Transition Between Modes

Command Structure
Command

..............................

ooooooooooooooooooooooooooooooooooooooo

Repertoire

.......................................

Input Commands

......................................

Editing Commands

oooooooooooooooooooooooooooooooooooo

Output Commands

oooooooooooooooooooooooooooooooooooo

Special Characters and Functions

OPERATING PROCEDURE

Loading Sequence

...........................

.....................................

nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn

Loading The Binary Loader

..............................

Loading The Symbolic Editor With The Binary Loader
Loading A Symbolic Tape Using The Editor
Editing A Symbolic Tape
Error

Messages

.........

............

2-2

...............

2-2

oooooooooooooooooooooooooooooo

2-3
2—4

oooooooooooooooooooooo

oooooooooooooooooooooooooooooo

Append ix
SUMMARY OF SYMBOLIC EDITOR OPERATIONS

HIGH-SPEED VERSION OF SYMBOLIC EDITOR

oooooooooooooooo

aaaaaaaaaaaaaaaaaa

ILLUSTRATION
Figure

Program Listing of Addition Routine

2~I

.......

...................................

Punching The Corrected Symbolic Tape

Example OF Use

1—3

ooooooooooooooooooooooooooooo

2-6

INTRODUCTION

The PDP-8 Symbolic Editor allows the user to prepare and edit symbolic tapes
in ASCII code with the ASR-33 Teleprinter on line.

The tedious task of cor-

recting symbolic program tapes using the ASR-33 off line is thereby avoided.

Proper use of the POP-8 Symbolic Editor can substantially ease the labor and
reduce the number of passes necessary to correct symbolic program tapes.

The Editor reads a page,

section, of symbolic tape into a butter in core

storage, where it is available for examination and correction.

The page

butter occupies all of care not taken up by the Editor itself and has a capacity

When the Editor has finished reading a

of approximately 6000 characters.
page,

bell rings to signal the user to commence editing.

The user may then

call for a listing of individual (numbered) lines, in any order, and insert desired changes and corrections.
or

In addition, text may be added to the butter,

inserted between specified lines.

be deleted by a single command,

Groups of lines or individual lines may
the entire page may be erased if desired.

Upon command, the Editor will then either list or punch out the corrected lines
or

page on paper tape.

The Editor can also be used to generate a new sym—

bolic tape by typing input directly on the console keyboard.

vii

CHAPTER

OPERATING

FEATURES

8y convention, paper tape information is organized into variable sized blocks, called pages
and 533.

Pages are separated on paper tape by ASCll form teed codes,

by carriage return/line teed pairs.

and lines are separated

A page of text may contain up to 60 lines of heavily com-

mented text; it can hold up to 240 lines without comments or formatting.

cludes the terminating carriage return/line teed combination.
are

Each line at text in-

All lines in the memory butter

implicitly numbered in decimal notation starting with T. This implicit enumeration is con~

tinually updated by the Editor to take account at line insertions and deletions.

For editing and

listing purposes, each line is referred to by its current implicit decimal number on the page.
Since the form teed code is not stored in core memory, there are no page divisions in the text

buffer; the entire contents of the butter are treated as a single page.

However, the user may

organize the contents at the text butter into several pages if he so desires.

MODES OF OPERATION
To distinguish between editing commands and the actual text to be entered in the butter, the
Editor operates either in the Command Mode or Text Mode,
made all
to

respectively.

ln the command

input typed on the ASR-33 Teleprinter will be interpreted as commands to the Editor

perform some operation, or to allow the operator to perform some operation, on the text

stored in the buffer.

In the text made, all
M

inserted into,

typed input is interpreted as text to replace, be

appended to the contents of the text butter.

Transition Between Modes

After being loaded into care memory the Editor is in the command mode; that is, the program
is waiting for a command.

The user types the desired command code and terminates it by strik—

ing the carriage return (RETURN) key.

This nonprinting character (hereafter represented by

i-l

“J“

tells the Editor to carry out the command~—to either replace, insert,

append the data. The

Editor then enters the requested text mode and responds with a line feed character (represented

byé

soon

it has processed the command and begun the operation.

After the Editor has entered the text mode, the user types the desired corrections or insertions.

When finished, he strikes the FORM key with the CTRL key depressed.

This special combination

character generates the form feed code which tells the Editor to return to the command mode.
A bell rings to indicate the transition back to the command mode.

COMMAND STRUCTURE
A command directs the Editor to perform a desired operation.

Each command consists of a single

The command letter tells the editor what to

letter, preceded by zero, one, or two arguments.

do; the arguments usually specify which numbered line or lines of text are affected. (Some argu-—
ments consst of

special characters? see below.)

Commands to the Editor must take one of the

following forms, where E represents any command letter and the symbol) represents the non—
printing character for carriage return (RETURN key);

Type of Command

Command Format

No Argument

One Argument

nEg

Perform operation "E” on the referenced

n,mEg

Perform operation "E” on lines 2 through
m, inclusive.

Two Arguments

Meaning
Perform operation "E"

line.

The arguments m and n, which refer to numbered lines in memory,

must

be positive and m must

be greater than n.

Two arguments must be separated by a comma, but no comma is allowed between the argument(s)
and the command.

Note also that in order to be executed a command must be followed by a

carriage return (g )
line feed code

When the RETURN key is depressed during operation of the Editor, the

(% ) will be automatically generated by the Editor.

COMMAND RE PERTOI RE
Commands to the Editor are grouped under three general headings:

lnput Commands
Editing Commands

Output Commands
A listing and explanation of the three types of commands is given in the following tables.

Unless

otherwise noted, the Editor returns to the command mode after completing each operation speci—
fied by a command.

The Editor will print an error message consisting of a question mark whenever the user has re-

quested nonexistent information or used an inconsistent or incorrect format in typing a command.
For example, if a command requires two arguments, and only one (or none) is provided, the

Editor will

print "?” and ignore the command as typed.

for a command that does not require one,
error

Similarly, if an argument is provided

if a nonexistent

message “?“ will be typed and the command will be

command character is typed, the

ignored.

lnput Commands
Action and Explanation

Command

EEAD a page of text from paper tape reader.
mation from the input tape until

tion) is encountered.
to

form feed (FORM/CTRL key combina-

All incoming text except the form feed is appended

the contents of the text buffer.

mains there

The Editor will read infor-

information already in the buffer re-

fPPEND the incoming text from the ASR-33 teleprinter keyboard to the
information already in the buffer (the buffer may be empty initially).

The Editor will enter the text made upon receiving this command and the
user

may then type in any number of lines of text.

The new text will be

appended to the information already in the buffer, or entered into an
empty buffer, until the form feed (FORM/CTRL) key combination is struck.

By giving the APPEND command with an empty buffer, a symbolic program
tape may effectively be generated on-line by entering the program via the

keyboard

in both of these commands, the Editor returns to the com—
mand mode after reading the form feed character.

NOTE:

Editing Commands
The following commands permit deletion, alteration,
Comm and

expansion of text in the buffer.

Action and Explanation

KILL the entire page in the buffer.
and "." are set to zeros

mode

nD)

The values of special characters "/"

(See below.) The Editor remains in command

QELETE line 2.

Line 2 is removed from the text buffer.

all succeeding lines are reduced by one,

n,mD)

rEELETE lines nthrough m, inclusive.
the new line nu

operations

nl)

The numbers of

is the line count.

The line following line m becomes

The Editor remains in command mode after all DELETE

LNSERT the typed in text before line n, until a form feed (FORM/CTRL) is
encountered;

The Editor enters text mode to accept input.

The first line

typed becomes the new line :1. The numbers of all lines following the in—
sertion, as well as the line count,
inserted.

are

increased by the number of lines

To reenter the command mode, the FORM/CTRL key combination

must be depressed;

if this is not done, all subsequent commands will be

interpreted erroneouslly as text to be entered in the program

nC)

SHANGE line 31. Lineflis deleted, and the Editor enters text mode to
accept input,

The user may new type in as many lines of text as he desires
i~4

in place of the deleted line.

lfmore than one line is inserted,

lines will be automatically renumbered.

subsequent

Return to the command mode is

accomplished by depressing the FORM/CTRL key combination.

n,mC)

CHANGE lines 2 through 11, inclusive.
routine and lines

This routine calls the DELETE

2 through 93 are deleted, allowing the user to type in

any number of lines (or none at all) in their place.
must

The FORM/CTRL keys

be depressed to return the Editor to the command mode.

When lines are changed or deleted the space previously occupied is not
recovered.

Thus,

it is possible to overflow the buffer by changing

and/or

deleting lines. This possibility may be readily eliminated by logically
segmenting a program into pages of 40 or 50 lines.

Output Commands
Output commands are subdivided into list and punch commands.

List commands will cause the

printout on the ASK-33 Teleprinter of all or any part of the contents of the text buffer to permit
examination of the text.

Punch commands provide for the output of corrected text or for the

duplication of pages of an input tape.

All

punch commands halt the computer.

List or punch

commands do not affect the contents of the buffer.

List Commands

The following commands cause part or all of the contents of the text buffer to be listed on the
ASR-33 Teleprinter.

Command

Action and Explanation

LlST the entire page.

the text buffer

nL)

_l___lST line n.
a

This causes the Editor to list the entire contents of

This line will be typed out, followed by a carriage return and

line feed.

l—5

LIST lines n through m, inclusive.

n,ng

Lines n through m will be listed on the

teleprinter. The editor remains in the command mode.

Punch Commands

The following commands will punch out corrected text or duplicate pages from the input tape.
Note that all punch commands halt the computer,

allowing the user to turn on the paper tape

punch.
Command

Action and Explanation

PUNCH out the entire contents of the text buffer.

has no provisions for generating

leader/trailer code.

page 2-6, for the procedure to generate

See Operation,

leader/trailer.

BUNCH line 2.

nPg

BUNCH lines 9. through m, inclusive,

n,mP;
F)

Note that the Editor

form feed.

the paper tape punch.

The Editor punches approximately 1 inch of 200 code,

feed character and approximately 5 inches more of 200 code.

puter then halts,

form

The com—

allowing the user to turn off the paper tape punch

ing the CONTlNUE key restarts the Editor.

Press-

This command is used to

logically divide a program into pages for reediting.

The assembler will

ignore the form teed.

SPECIAL CHARACTERS AND FUNCTIONS
A number of keys have special operating functions for use by Editor control.

their associated functions are listed below.

These keys and

The first three are nonprinting; the symbols in

parentheses are used for purposes of illustration

Carriage Return (EL?
in both command and text modes,
to process

striking the carriage return key (RETURN) signals the Editor

the information just typed

in command mode, the specified operation will be
l—o

performed following this terminator.

ln text mode,

the

preceding

line of

text

will be

placed in the text butter.

Line Feed (

)

The lines on each page of text are separated by the carriage return/line teed (CR/LE) combin~
ation.

When a line is terminated by striking the RETURN key, the Editor program will auto—

matically generate the line feed code.

Line feeds will be ignored on input, but are automatically

regenerated after each carriage return on output.

Back Arrow (<--—-—- )

The back arrow (<—-———~) is used for error recoveries in both text and command modes.
in text mode,

When used

(<--——-) cancels the entire line. The user continues typing on the same line.

When

typing commands, (<——-—-) cancels the line as it was written and the Editor then generates a carriage return/line feed (CR/LE) combination.

Rubaut (R0) and Leader/Trailer Code (200)

When read from paper tape, rubouts,

ignored

leader/trailer code (200), and blank tape are completely

Tabulation (———>l ) and Switch Register Bit l Option
When the TAB key is struck in combination with the CTRL key, the Editor produces a tabulation.
TAB

(—bl ) generates up to ten spaces to the next tab stop

keyboard or the paper tape reader.

input from either the ASR-33

On output, the tab spaces are generated or suppressed in

accordance with the setting of switch register (SR) bit position i:

it SR bit l is in the down (0) position, spaces will be generated in place of tabs.

it SR bit l is in the up (1) position, tabs will be generated.

The Editor cannot replace spaces with tabs until a tab has been inputted.

l—7

Form Feed (FORWCTRL Combination)

The form feed is generated by depressing the FORM/CTRL key combination.
to

lt directs the Editor

leave the text mode of operation and return to the command mode.

Slash (/)

The slash symbol (/) stands for the numerical (decimal) value of the last line of the current page
stored in the text butter.

mand

/ngill

cause

It may also be used as part of an argument.

For example, the com—-

the last line in the text buffer to be listed.

Period ()

The period

symbol (.) stands for the numerical value of the line currently being processed. The

period may be used as part of an argument.
user

Far example, the command

l5, .C) will allow the

change line l5 to the current line by deleting the old data and replacing it with data

entered via the ASR~33 keyboard.

After a delete command (D) has been executed, the period symbol stands for the number of the
line preceding the first deleted line.

For example, it lines l5 to 23 of the current page have

been deleted by giving the command

"l5,23D3", the period will equal line 14 after execution

of the command

Equal Sign (z)
When the equal sign is typed in the command mode, the Editor will print out the decimal value
of the argument that precedes it, followed by a carriage return.

The symbol may be used to

determine the number of lines of text in the butter (indicated by "/") or the value of the cur—
rent

line (indicated by

".“).

For example,

/=59 indicates that there are 59 lines in the text buffer (i .e., the decimal value of the last
line is 59).
and

.227 indicates that the current line is numbered "27".

and

/—6:53

Minus Sign (-)

Arithmetic subfrocf:

This may be used to combine symbols in orgumenfs.

/—o, /l.gwill list the losr seven lines of the text buffer.
Space (L4)
Arithmefic addition:

This may also be used as is the minus (~).

Fer example;

.-l, .L..._Jl L) will lisf the line preceding the current line, the current line ifseli,

following the curren’r line.

and rhe line

CHAPTER

OPERAHNG

PROCEDURE

This chapter describes the sequence of operations necessary to load, edit, and punch out a
corrected symbolic program tape, and gives examples of the

use

of the Editor.

After the Editor has been loaded, it may be used to read into the text buffer a page of the sym—

bolic program to be corrected.

When the page has been read in and a form feed code has been

encountered, the Editor strikes a bell to signal the user that the Editor is in the command mode.
Corrections and additions may then be either typed in from the ASR~33 Teleprinter keyboard or
inserted from paper tape via the reader.
to

permit insertions, deletions, or changes.

appended to the end of a section.
deleted upon a single command.

Text may be inserted between specified lines or

Individual lines, groups of lines,

begins.

entire page may be

Finally, the corrected lines, groups of lines,

the entire page may be listed and/or punched.

core

or an

To ensure that a tape is correct, desired portions or an entire

page may be prelisted before punching
or

Individually numbered lines may be listed in any order

The original text remains available in the

buffer in case further corrections are necessary

The following paragraphs give the detailed procedure for loading the Editor and a symbolic tape,

making required corrections, and punching the corrected symbolic tape.

LOADING SEQUENCE
Before editing can begin, the Symbolic Editor program must be loaded into care with the

Binary

Loader (Digital~—8-2-—U~Rim), and the symbolic program tape to be corrected must be read into

the core text buffer.

The loading of the symbolic tape is performed by the Editor itself under

keyboard control.

Loading The Binary Loader
The Binary Loader is loaded into core by the Read-“In Mode (RIM) Loader.
is initially placed into core memory by PDP-8 console keys and

The RIM Loader itself

switches, as is explained in

Digital—8ml—U. When this has been done, the RIM Loader is used to load the Binary Loader
into care by means of the following procedure:
1

Put the

Binary Loader tape in reader.

Set the SWlTCH REGiSTER (SR) to 7756, the starting address of the RIM

Loader.

Press the LOAD ADDRESS key and then the START key.

Turn on the reader and wait until the tape is completely read in.

the reader stops, the

When

Binary Loader is in memory.

Loading The Symbolic Editor With The Binary Loader
To load the Symbolic Editor with the
set

Binary Loader, place the Editor program tape in the reader,

the SR to 7777 (the starting address of the BlN Loader), press the LOAD ADDRESS key and

then the START key,and turn on the tape reader.
memory

When the reader stops, the Editor is in core

It the ACCUMULATOR (AC) does not contain zero when the reader halts, a checksum discrepancy
exists which indicates that the Editor tape has been read in incorrectly.

Load the tape again

by repeating the procedure described above.
To start the Editor program

the START key.
are

initially set the SR to l76, press the LOAD ADDRESS key and then

The loading of the symbolic tape to be edited and all subsequent operations

performed through the use of the Editor by giving appropriate commands from the Teletype

keyboard

Loading A Symbolic Tape Using The Editor
1

Place the symbolic tape of the program to be corrected in the paper tape

reader.

2—2

At the ASK—33 keyboard, type the read command foliowed by a carriage

return

(i .e., type ”R)“).

Turn on the reader.

The symbolic tape will be

read automatically into the text buffer.

The Editor will continue reading the tape until either the text buffer

in core is almost full

(full capacity is approximately 150 lines) or the form

fe___§_d code is encountered at the end of the tape.

it the tape contains no

form feed code, strike the FORM/CTRL key combination after the tape has

been read in.

Upon recognizing the form feed character, the Editor enters

the command mode and rings a bell to indicate that it is ready for the first
command

CAUTION

If the form feed code is encountered before the symbolic tape has

completely read in (as indicated by the ringing of the bell), turn
off the paper tape reader. Otherwise, characters on tape will be
interpreted as commands to the Editor. The section of tape read in
up to the form feed code should then be edited first before pro-

ceeding with the remainder of the tape.

EDITING A SYMBOLIC TAPE

The actual editing procedure depends, of course,

particular user‘s requirements.

eral procedure is illustrated in the example that follows.

For input,

The gen—

editing, and output com-

mands that may be given to the Editor, refer to the detailed explanation of the Command Structure,

Command Repertoire and Special Characters and Functions under Operating Features (see pages
i~2 through l~9)or see the corresponding summaries of commands and special characters in the

Observe also the following operating notes and precautions:

appendix.
i

Terminate each command to the Editor by striking the RETURN (carriage

return) key. This directs the Editor to execute the command
2.

After a command to insert,

change, or append text to the symbolic pro-

gram has been executed, the Editor remains in the text made until the operator

hits the FORM/CTRL key combination on the teletypewriter.

This combina—

tion generates the form feed code character, which tells the Editor to return
to

the command mode.

if a great deal of text is added during the course of editing, the text

buffer may overflow (full capacity is approximately 150 lines).

the Editor rings the bell and returns to the command mode.

If this occurs,

Text entered

after the buffer is full is ignored, and the contents of the buffer are not distu rbed

The Editor may be stopped at any time by pressing the STOP key; to con-

tinue press the CONTINUE key.

If it is desired to restart the Editor without

disturbing the butter, place octal address 177 in the SR and press the LOAD
ADDRESS and the START keys.

restart,

If it is desirable to clear the buffer and then

place octai address T76 in the SR and press the START key.

Error Messages

The proper rules for giving commands containing from zero to two arguments must be observed

during editing,

explained under Operating

Features (page

If commands

1—2).

are

given in an incorrect format, or if arguments are either missing or extraneous, the Editor will

respond with an error message by typing out a question mark.

legitimately take from zero to two arguments.

Notice that some commands can

in general, if an argument is either missing or

extraneous, the Editor types out “?” and ignores the command.
ment is encountered or

the error message

Similarly, if a negative argu-

illegitmate command again is typed, the Editor again responds Wit-l1

PUNCHiNG THE CORRECTED SYMBOLIC TAPE

The procedure for punching out the corrected symbolic tape depends to some extent on the user's

requirements. The general sequence of steps is given below:
give the output command to punch out either iine n of the

As desired,

text

(nPR), lines 3 through ff} (n,mP)), the entire text (PA),
2-4

form feeds

(F)).

After the carriage return

() ) following the punch command

has been

received, the computer will halt. Turn on the punch.

NOTE:

The Editor has no provisions for generating leader/trailer

If leader/trailer code is to be punched, switch the ASR~33
Teleprinter to LOCAL (off—line), generate as much leader/trailer

code.

(code 200) as needed, and then switch the teleprinter back to LINE
(on—line). To produce the code 200 leader, simultaneously press
and hold the CTRL and SHIFT keys with the left hand; press and
hold the REPT key; press and release the@ key. When the required
amount of leader has been punched, release all keys.
To produce
the 377 code, simultaneously press and hold both the REPT and
RUB OUT keys until

sufficient amount of leader has been punched.

After the Editor has finished the punch operation,
trailer code may be generated in the some way.
3.

Ieader/

Press the CONTINUE key at the console to start punching.

If a tabulation has been produced by giving the TAB (———>l ) command, the
tab spaces will automatically be generated on output.
to

be suppressed during punchout,

position
4.

set

If the tab spaces are

SR bit I at the console to the up (l)

After a tape has been punched,

further commands.

turn

off the punch before typing any

If this is not done, the control codes typed in will be

punched on the symbolic tape.
5.

Punching the symbolic program does not delete it from memory. The page

remains in the text buffer in core until the KILL command
erase

it.

As the tape is punched,

(K)) is given to

listing of the actual tape is simultan-

eously printed. Thus, last minute errors may be spotted and corrected by
further editing.

If this is necessary, the affected lines

the buffer by use of the Editor.

may be recalled from

If there are no errors, the correct listing of

the symbolic tape is immediately available.

If it is desired to read another

tape into the buffer, the user must first delete the entire page at text

Remember that the recommended [page length,
is 60 lines or less.

“(d)“

delimited by the form feed,

However, the Editor will accept more text if necessary.
2~5

EXAMPLE OF USE

The following detailed example of the editing of a page of text is intended to familarize the
user

with the basic operations of the Symbolic Editor.

Where details of the loading sequence

and operating procedures are not shown, it is assumed that the user has followed the correct

procedures previously explained.
This example concerns a program for adding up numbers stored in locations 200
of the computer, with the answer to be stored in location
tion 600.

through 207 8

4l08. The program is to start in loca-

The program listing is shown in Figure l.

/ADD

NUMBERS

*600

BEGN:

HLT

ZTO

START

THE

/THE

FIVE

PROGRAM.

CLA
TAD
DCA
'TAD

DCA

"CONTINUE"

HIT

INSTRUCTIONS

CONSOLE

ROUTINE

THE

INITIALIZE

M10

/CLEAR THE ACCUMULATOR
/LOAD AC WITH THE NUMBER

COUNTR
TWOHUN
POINTR

/PUT INTO COUNTER
/LOAD AC WITH FIRST ADDRESS
/PUT IT INTO POINTER

"10

/THE

BEGN:

SEVEN

INSTRUCTIONS

/THE NEXT
M10:
TWOHUN;
ANSWER

THREE
~10

/THE NEXT
COUNTR»
POINTR:

TWO
O
0

THE

ARE

PROGRAM

ITSFLF

/ADD NEXT NUMBER
/INDEX POINTFR

TAD I POINTR
132 POINTR
ISZ COUNTR
JMP BEGN
DCA I ANSWER
HLT~
JMP BEGN+1

IS IT
lINDEX COUNTER:
/NO3 CONTINUE ADDING
/YESB
STORE ANSWER

/HALT

REGISTERS

CONTAIN

200

THE CONSTANTS
/NEGATIVE TALLY NUMBER
FIRST ADDRESg IN BLFFER

410

REGISTERS

ARE

RESERVED

FOR

VARIABLES

Figure l

ZERO?

Program Listing of Addition Routine

Let us assume that we have attempted to assemble this program using the PDP-8 Symbolic As—

sembler (PAL Ill).

On PASSl,

BEGN

'AT

0506

ADDRES

0616

ANSWER

0612

UA
BUFFER
AT
0620
COUNTR

0616

BEEN

‘

however, the Assembler typed the following:

0600

FIRST

0616

M10
POINTR

0615
0621

TWOHUN

0616

The message DT GEGN AT 0606
to

signifies that the programmer has mistakenly used identical tags
An inspection at the program

specify two different addresses.

the tag “BEGN” has,

HLT,

indeed, been duplicated.

listing (Figure 1) shows that

It appears in line 3 of the

then in line l4, starting with ”BEGN, TAD l POlNTR."

listing as "BEGN,

(Since the line numbers are

implicit only, they are not shown in the example; they may be obtained by counting from the
top down in Figure l .) To correct the situation, the Symbolic Editor was read in with the Binary

Loader,
was

explained under Loading Sequence in this chapter. The symbolic tape to be corrected

then loaded through the Editor by means of the READ

were

given:

(R) ) command. A

series of commands

(the lines typed by the Editor have been underlined for clarity).
R

14L

BFGN;

TAD

POINTR

/AfiD

NLNBER

14C
ADDR:

TAD

POINTR

/ADD

NLMBER

JMP

BEGN

/NO:

CfiNTINUE

JMP

ADDR

/NQ}

CONTINUE

17L
ADDING

17C
13:18L
/THE NEXT
ADDR’

INSTRUCTIONS
POINTR
POINTR
COUNTRH
ADDR

SEVEN
TAD
ISZ
132

JMP

(DOA

answee_q

ARE

THE
/ADD

PROGRAM
NEXT

/INDEX

ITSigF

NUMBER

pOTNTER

COUNTER;
/N03 CONTINUE
STORE
/YES;
/INDEX

ANSWER

25L

QNSWER

410

25C

ANSWER,
24L

410

TweHUN,
2 4C
TWOHUN:

200

FIRST ADDRESS

200

/FIRST

9—1».

BUFFER

ADDRESS

BUFFER

M10,

~1n

IWQHUN,

260

ggswee,

A19

/NEGATIVF TngLY NUMBER
/FIRST ADDRESS IN BurBEB

Having made the desired corrections, the programmer finally asks the Editor to punch out the
entire text on tape by giving the punch

(Pd ) command, but still withholds

(Kg ), pending final corrections. As the tape is punched out,

a new

the KlLL command

program

listing is simul—

taneously printed out and the entire text is preserved in the buffer.
/ADD

NUMBFRS

#600
BEGN,

HLT

/TO

THE

START

PROGRAM.

HIT

”CONTINUE"

CONSOLE

/THE

NEXT FIVE
CLA
TAD
DCA
TAD

DCA

INSTRUCTIONS INITIALIZE THF ROUTINE
ICLFAR THF ACCUMULATOR
M10
/LOAD AC WITH THE NUMBER ~10
COUNTR IPUT INTO COUNTFR
TWOHUN /LOAD AC WITH FIRST ADDRESS
POINTR /PUT IT INTO POINTER

lTHE NEXT
ADDR:

/THE
M102

TWOHLUN
ANSWER:
ITHF

COUNTR:
POINTR;

SEVEN INSTRUCTIONS
TAD I POINTR
ISZ POINTR
ISZ COUNTR
JMP ADDR
DCA I ANSWER
HLT
JMP BFGN+1
THRFF
~10
200
410

TWO
O
0

REGISTFRS

REGISTERS

ARE

THE PROGRAM ITSELF
/ADD NEXT NUMBER
llNDEX POINTER
IS IT
IINDEX COUNTER»
/N03 CONTINUE»
STORE ANSWER
lYES;
IHALT

‘

ZERO?

CONTAIN THF CONSTANTS
INFGATIVF TALLY NMwBFR
/FIRST ADDRESS IN BUFFFR

ARE

RESFRVFD

{fit}

The PASSl result of assembling this program is:

2-8

FOR

VARIABLFS

RWN

ABCMPTDNEOIOWDSGUOIO 670516
T. R

NH TU RN.

APPENDIX

SUMMARY

SYMBOLIC

EDITOR

OPERATIONS

SpeciaI Key Functions
carriage return (RETURN key)

CompIete specified action.

form feed (FORM/CTRL

Leave text mode.

key combination)

back arrow (4.”)

Text mode:

canceIs entire Iine.

Command mode:

canceIs Iine as

written; Editor generates carriage

return/Iine teed (CR/LF) combinafion.

tabuIation (TAB/CTRL

combination)

input generates up to ten tab

spaces to next tab stop.

Tabula-

tion may be suppressed on output

by placing SR bit I to up (I) position.

Editor Command Summary

Command
R

No. of Arguments

Function

Read incoming text from reader and

append to text buffer.
Append incoming text from teIeprinter.
KiII page of text in text buffer.
nD

DeIete Iine n of text.

n,mD

DeIete Iines n through m, inclusive.
AI-I

Insert text before line n.

Change line 2 of text.

Change lines a through E, inclusive.

List entire page of text.

List (print) line

n,mL

List lines

Punch the entire contents of the buffer.

Punch line .9. of text in buffer.

Punch lines 2 through

Punch form feed code.

_r_i_ of text.

2 through Ln, inclusive.

E, inclusive.

Special Arguments
Meaning

Argument
Slash (/)

Decimal value of last line of current page

Period (.)

Decimal value of current line being processed

Equal sign (=)

When typed in command mode, decimal value of argument

preceding it will be printed out.

For example,

/=58 indicates that last line is 58; and .=24 indicates
that current line is 24.

Al -2

APPENDIX

VERSION

HIGHeSPEED

SYMBOLIC

EDITOR

There are several differences in the Editor command structure when using the high—speed version.

These arise because of the independence of the keyboard/high—speed reader and teleprinter/

high—speed punch

Command summary (only those commands which are different are listed):

Read a page of text from the high—speed reader and put into the
core

text

The Editor will ring the bell and return to the

buffer.

command mode when either
I

form feed character was read (signifying end of

the logical page)

P)
nP)
n,mP)

the tape ran off the end (did not have a form feed)

the buffer has overflowed

Punch onto the high—speed punch.

Does not halt the computer.

The Editor returns to the command mode when done.

The text

in the buffer is unchanged.

Punch

leader/trailer code (blank) on the high-«speed punch

Editor remains in the command mode.

Punch some blank tape,

highuspeed punch

nN)

form feed, and some blank tape on the

The Editor remains in the command mode.

Punch and read in pages of text.

This is equivalent to

F)
K
R

repeated n times

The Editor returns to the command mode when done

A24

This is equivalent to 4.11

alt mode

It examines the next line.

This is equivalent to

.-1L)

‘

It examines the previous line.

A2—2

«1’

Z... W"

dflEflflEfl

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Parsippany, N. J.
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-

534

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U.S.A.

20-8/65