Nuclear Data BASC-12 General Assembler assembler Software Instruction Manual

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Document

NUCLEAR DATA, INC.

Post ()ffice Box 451

Palatine, Illinois

60067

January, 1971

1M41-0001

SOFlWARE INSTRUCTION MANUAL

BASC-12 GENERAL ASSEMBLER

Printed in U. S.A.

Section Title

INTR()DUCTION. • •

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...

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Page

1-1

A. Program Summary

0 • • • • • • • • • • • • • • •

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B. Program Area • • • • • • • • • • • • • • • • • 1- 1

C. Starti ng Address. " • • • • • • • • • • • • • • • 1- 1

D. Equipment Confi guration. • • • • • • • • • • • • • 1- 1

E. Definitions • • • • • • • • • • • • • • • • • • 1-1

2 PROG,RAM DESCRIPTION

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2-1

Appendices

OPERATOR OR USER CONTROt

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3-1

OPERATIC)NAL PROCEDURE

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4-1

ERROR DIAGNOSTICS. • •

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B c

INSTRUCTIONS IN MN"EMONIC SEQUENCE • • • • • • • A-1

I NSTRUCTIONS IN OCTAL SEQUENCE • • • • • • • • • B-1

ASCII CHARACTER SET

• • • • • • • •

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C-1 iii

1. INTRODUCTION

A. PROGRAM SUMMARY

BASC-12 is a 2-Pclss Assembler (optional 3rd pass) for the ND812 Central Processor.

BASC-12 translates symbolic mnemonics (source) into machine instructions (object), executable by the Central Processor hardware. The BASC-12 Language is structured to give the programmer compl ete control over the mach ine language instructions to be executed by the processor, while allowing easily remembered and understood symbols

(letters, numbers, and special characters) to specify the desired instructions. BASC-12 is designed to run in a 4K Processor equipped with paper tape and/or magnetic tape cassette peripheralls.

B. PROGRAM ABEA

0000

8 through 5303

8 with locations 3053

8 through 41768 used as the Input Buffer. c.

STARTING ADDRESS

020°8·

D. EQUIPMENT CONFIGURATION

Minimum requirements are a 4K ND812 Central Processor equippeOd with an ASR33 Teletype

(Io~ speed punch/reader). Optional peripherals include the high speed punch or reader and/or a Magnetic: Tape Cassette Unit.

E. DEFINITIONS

1. Source

The Symbolic Program irs written by the programmer in the symbols allowed in BASC-12 language. The program source (usually punched on tape) is the input to the .Assembler which then "assembles" or "translates" it into a machine language or "binary" version of

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of the program. The Symbol ic Text Editor (ND41-0002) is usually employed to prepare a "Source" tape.

2. Binary

The output from an assembler is often referred to as the "Object Program". If the Object

Program is not produced in directly executclble form by the Assembler, it must either be assembled further, or else must be loaded and executed with a run-time monitor which interprets the object coding and performs the required operations. The output from the

BASC-12 Assembler mClY be loaded without modification as it is in absolute binary form, so that, once in core, it is executed directly by the processor without the need for a run-time monitor. To distinguish this type of object program, it will be referred to as the

Binary Output or simply "Binary". Therefore, a binary file is a one-to-one copy of core which may be loaded and executed directly.

3. Listing

This consists of a hard-copy symbolic listin!~ of the program with the octal equivalents of the assembled insf'ructions and their octal locations in memory. It represents the documentation of the program, including the actual instructions assembled, and their execution locations. The fCirmat used is:

2345 6740 SYMBOLIC LINE OF C()DING, where "2345" and "6740" are octa

I numbers representi ng a memory address and the contents of that address respectively. The balance of the line consists of a repetition of the Program

Source which was assembled to yield the m(lchine instruction "6740

•

4. Numbers

All absoluJe numbers eIre interpreted by the: BASC-12 Assembler as four-digit octal numbers. The hi~,h order digits of longer numbers will be ignored. The decimal digits

"8" and

"9" wi

II be interpreted as non-numeric ,characters.

5. Characters

A single letter, number, etc. When referred to paper tape, a character occupies one frame.

6. Symbols

A symbol consists of any collection of lette:rs, numbers, or other characters appearing anywhere on a

I ine, not in a comment, and followed by a term inator.

N()TE

Spaces ane terminators.

1-2

A legal symbol should be no more than 6 characters long and must begin with an alphabetic character. Longer symbols are allowed bU1' will be truncated to

6 characters with the excess being ignored. Thus, the symbol IISTARTS II , "STARTSAII, and "STARTSAB II will be interpreted as the same symbol by the Assembler, namely IISTARTII.

Non-Printing Characters

The following symbols are used to represent non-printing symbols:

Horizontal Tab

Vertical Tabe

Carriage Return =

Line-Feed =

These characters, although non-printing, may be typed by the user on the keyboard and may appear in a Program Source. They generally initiate some action in the printing device (such as a carriage return) or cause a special response from a program (such as a tab) •

A space is repres€!nted by the symbol II

A " even though it is a printing character in the sense that it causc~s the carriage to move one column to the right.

It is, however, often important to know how many spaces appear in a line of text, so that it is convenient to have a symbol to repr€!sent it in the documEmtation •. None of these special symbols are never printed, but are used whenever necessary to clarify the contents of a I ine of text in the examples and discussions which follows. -

8. User Entry

User entry is alwclYs underscored. All other characters are prin'ted by the program.

9. Ignored Charolcters

A character lIignored" by the BASC-12 Ass,embler is reproduced in the listing, but does not affect assembly of the program. Ignored characters will terminate a symbol, but otherwise initiate no special action. The "Space ll is an example of an ignored character. If spaces intervene between a symbol and another sp,ecial character, the assembler interprets the resulting coding os though the spaces were not present. Spaces between symbols serve only to separate the symbols.

10. Term i nators

•

The following charracters have special meaning to the Assembler and will also terminate a symbol: Comma (,), Slash

V),

Asterisk

(*),

Plus

(+),

Minus (-), Equal

(=), ,'-lumber (#),

Left Bracket ( [ ), At (@), Horizontal Tab

), Vertical Tabe (

Arrow ( t ),

Carriageo-Return ( f),

Form-Feed, Up

.;», and Dollar

($).

B lank tape, rubouts, and line-feeds are not stored in the Assemb I er buffer. Twenty-four consecutive Rubouts are interpreted as an out-of-tape condi ti on •

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Space ( a )

Comma (,)

Slash (/)

Asteri sk

(*)

Plus

(+)

Minus (-)

Equal

(=)

Selves only to terminate a symbol. Spaces are otherwi se ignored.

Indicates that the symbol preceding it (ignoring spoces) should be interpreted as a tag for that

I ocati on. The symbol is set equal to the Program

Location Counter (PLC).

A symbol may not be used as the tag for two different program locations.

Command mnemonics may not be used as tags.

The slash indicates the beginning of a comment.

All characters, including the terminators, following

""il1c; slash will be ignored by the assembler until the next carriage-return. The Number sign

(#) wi

II be flqgged as an illegal character. Comments, including the Slash, are ignored and are reproduced only in the Pass

3 Li sting.

The asterisk is an instruction to the assembler to reset the program location counter (PLC) to the vallue of the symbol (s) following the asterisk.

If the asterisk is followed by several symbols, they wiH be assembled according to the rules of assembly applying to a single location and the PLC will be set equal to the resul t. Numbers are, as usual, interpreted literally. Octal numbers larger than four digits are truncated from the high-order end.

If c::my one of the symbols appearing after the

"*" have not been previously defined, the expression will be ignored and the undefined origin (UO) dicJgnostic printed.

CClUses the symbol following the plus sign to be added to the symbol preceding the sign. An undefined symbol at the time of evaluation is ignored.

Couses the symbol following the minus sign to be sylbtracted from the symbol precedi ng the minus sign.

Co!uses the symbol preceding the sign to be set equal to the symbol or symbols following the sign.

If the symbol following the equal sign is undefined, the Assemb I er reacts di fferently dependi ng on the current pass number and the type and ki nd of symbols

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Number

(#)

Left Brack ( [ )

At Symbol::

(@)

Horizontal Tab

(~)

Vertical Tab (

Form-Feed

Up Arrow ( t ) if ) involved. The treatment of statements containing an equal sign is discussed under "equivalence

Stntements" •

Denotes an illegal character. A character other thCln blanks, line-feeds, or rubouts, and with oc1'al code less than 0240 or greater than 0337 is stored in the inputbufferasa

11#".

When this character is encountered by the Assembler dud ng processi ng of i ts buffer, the message IIIC

AT XXXX" is generated where" XXXX" represents the current value of the PLC. If the character

"#11 appears in the user1s source, it will be interpre'ted as an illegal character during assembly.

Indicates that the symbol following the"

II is to be taken as an Assembl er Directive; that is, an instruction to the assembler to interrupt pro1cessing and perform some other task indirectly related or not related to processing the source program. The secti on on Assemb I er Directives describes the various directives included in the assembler and the procedure necessary to create user directives.

Indicates an indirect address for a memory reference instruction. The "@" symbol should appear immediately after the instruction mnemonic without separating spaces (i. e. "JMP@").

Equivalent to a space. When creating the Pass 3

Listing, the assembler will generate the proper number of spaces on the teletype or other output device. The output device need not have mechanical tabb i ng ab iii ty •

Terminates a line and advances the paper to the top of the next page.

Int,erpreted by the Assembler as a vertical tab.

Automatically generates a two word I/O where the symbol foil owi ng the up arrow is taken as the second word of the I/O. The octal code 0740 is cmtomatically generated in the first location of

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Carri age Return

Dollar

($)

Period or Dot (.) the! two word i nstructi on. Th i s symbol's acti on is an exception to the one location per line rule in t'hat it gen'erates two locations for one I ine of coding. It does not, however, restrict the prclgrammer's fl exib iI i ty of control over the finol binary program since use of ( ) is optional.

The! up arrow need appear only once on a line.

Succeeding up arrows on the same line are ignored.

Symbols precedi ng the up arrow on a line are ignored.

Carriage Return

(~) terminates a line of coding.

A location is not assigned to lines containing an

(=) or

(*) or b lank lines contai n i ng no codi ng or a comment only. Extra carriage-returns in the source, though they generate extra lines in the program listing, do not affect the length of the machine language program and may be used to format the listing for better legibility. It is recommended that b lank I ines be used to separate lo~~ical blocks of the Source and to separate the constants and variables from instructions.

The Dollar

($) indicates the end of the Source.

The dollar sign will initiate termination of the current pass and so should be the last symbol in a Program Source. If a dollar sign is not read by the! Assembler before it runs out of input tape, the assembler waits for teletype input to supply the

"$", indicating the end of the pass, or any other ch()racter indicating that the input device was reloaded and the assembly should continue with the additional source. The

"$" should not be used anywhere in the body of the source except as the last line.

Is equival ent to a symbol representing the current value of the Program Location Counter (PLC).

The period or dot does not serve as a terminator and must be used in all respects I ike any other symbol.

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2. PROGRAM DESCRIPTION

When using the BASC-12 Assembler it is imperative that the user have a solid knowledge of the source language. (See Appendix A Clnd B for a bri ef Ii sti ng of these.) The source program consists of ASCII coded binary words that represent symbols, special characters and terminators written in a format acceptable by the BASC-12 Assembler. The following example illustrates the statement format which can be interpreted by the BASC-12 Assem.bler:

LABEL

READ,

()PERATION

JMP

ADDRESS

ENID

ICOMMENT

NPUT ONE CHARACTER

Fields of each instruction line are not rigidly defined. They are separated from one another by any of the terminators except the

+ and - characters. Plus

(+) and Minus

(-) are used to connect multiple symbols to form a single field. The

+ and - signs are evaluated from left to right before a field is connected with another. Parentheses are not perm i tted •

The commend field must begin with a slash (/). A comment may start anywhere on the line and o'lways continues to the end of the line. -

It is suggested, in the interest of neatness cmd legibility of final output, that the OPERATION field begin in the ninth column (first tab), that the ADDRESS begin in the fourteenth column (automatic provision for inserting an extra space after 3-letter instructions is made in the Editor), and the comment begin in the 25th column (4th tab position; one tab after most instruclrions). On lines which contain no instructions or definitions, the comment may start anywhere on the line and is generally left-justified. A line containing a comment only is left-justified in Pass 3 output of the Assembler.

A. LABEL FIELD

The label field ll1(lY consist of one symbol followed by a comma. Plus

(+) and Minus (-) signs are not permitted in the Label Field. The symbol may not have been previously defined by appeadngin an equivalence s'tcltement or by having been used as a tag. There

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may be more than one tag on a line, but eClch may consist of only one symbol and each must be followed by a comma. All tags on the same line will reference the same location in the assembled program.

An attempt to use a symbol as a tag which has already appeared in an equivalence statement, or was used as

Oi tag, will result in the duplicate tag error diagnostic IIDT AAAAAA

AT XXXX" where the location counter at the time the error was detected.

The label field does not affect the contents of the current location.

B. OPERATION AND ADDRESS FIELDS

If, after assembling an element other than () label element, the result is between

2400a

- 7737a, the next· field will be treated as the address field of a Single-Word Memory

Reference Instrucf'ion. In this case, no field, except a comment, may follow on the same line. Each symbQiI beyond the Address field of a Single-Word Memory Reference Instruction will generate the Double Address Diagnostic ,IIDT AAAAAA AT XXXX

, where "AAAAAAIJ is the symbol and IIXXXX" is the value of the location counter at the line where the double address was detected.

Since Single-Word Memory Reference Instructions are recognized by their octal coding, it is possible for the user to devise his own mnemonics for special applications. In addition, the assembler will always recogniize error conditions involving Single-Word

Memory Reference Ins1Tuctions no matter how the octal code is 'created. This parallels the fact that the processor also recognizes

~nstructions by their octal codes and errors made in the Sourc:e wi

\I be carried through to run-time.

It should be noted that the Assembler does not check for the absence of the Address field.

If a Single-Word Memory Reference is assembled into a location and no address field is provided, reference to location

OOOOa will be assembled by default.

In any case, proper assembly of a Single-Vlord Memory Reference Instruction demands that it appear in i"he first non-label field on the line. Although not essential for proper assembly, the same rule should be applied to all instructions to minimize the possibility of error and to mClke the Source

Li sti ng easi est to read.

Fields evaluated to a number less than

2400a or greater than

7377 a are combined with an inclusive logical 1I0RIt. This allows micro-programming of the Operate and I/O instructions.

C. EQUIVALENCE STATEMENT

An Equivalence Statement consists of an 1I()bject Symbol II followed by an equal sign followed by an e>~pression consisting of symbols, plus signs

(+),

(=) minus signs (-), and spaces

(to separate symbols in the absence of a plus or minus sign). The expression is assembled according to the ctlgorithm for the assembly of an instruction and the symbol appearing to the I,eft of the equal sign is set equal to the result.

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D. DEFINITION STATEMENT

A Definition Statement is the special case of an Equivalence Statement in which all of the symbols appeclring to the right of the equal sign are defined when the statement is encountered. Ultimately, it is the purpose of all Equivalence Statements to assign an octal value to the object symbol or to set the object symbol equal to another symbol which has been assigned an octal value. In other words, it is the purpose of the Assembly to change all Equivcdence Statements into Definition Statements. "RD XXXXXX AT NNNN" indicates an attempt to assign a second value to the same symbol. The error diagnostic

"DT XXXXXX AT NNNNII is generated if a symbol appearing as the object of an Equivalence Statement also appears as a Progralll Tag (Where

XXXXXX" is the symbol and

"NNNN" is the current value of the Locaf'ion Counter).

Equivalence Statements are closely related to the use of symbols as Program Tags. Use of a symbol as a Program Tag sets it equal f'o the Memory Address assigned to the instruction or constant it tags. Since a symbol may have only one octal value, any attempt to also use the symbol as the object of an Equivalence Statement will generate the error diagnostic

"RD XXXXXX AT NNNN" and the prior vCllue of the symbol will not be affected.

Similarly, any atl:empt to use a symbol two or more times as the object of an Equivalence

Statement will generate the same error message: "RD XXXXXX AT NNNN" where "XXXXXX" is the symbol andIlNl'~NN" is the current value of the .Location Counters.

The Assembly of

Definition Statement is straight-forward if all of the symbols on the right-hand side of the equ~1 sign are defined. The Assembler will assemble the righthand symbols according to the algorithm used for instruction locations and set the lefthand symbol equal to the resul t. For exampl e, the statements:

DBSKIP

JMP .+3

CSLCT == 7466 would cause "DBSKIP" to be set equal to 6003 and "CSLCT" to be set equal to 7466 in the Pass

1 symbol table. Thereafter, the octal number 6003 would be substituted for

"DBSKlp lI whenever the symbol occurred.

A statement of thc~ form:

READ

JPS INPUT is a definition (and is handled as described above) only if both "JPS

IJ and "INPUT

II were defined or used as a tClg prior to the appearance of the above statement. If "I NPUT

II is used as a tag or appears in an equival ence statement after the above statement, then assembly of the above statement must be deJerred to a later pass at which time "I NPUT" will be presumably defined. In this case, "READII will not appear in the Pass

Symbol

Table. On the second or subsequent passes, "READ" will be properly defined and listed normally in the PC)SS 3 Symbol Table. The user should be aware, however, that IIREADII

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remains undefined until it is encountered during processing of Pass 2 or 3 and will generate an Undefined Symbol error diagnostic during Pass 2 or 3 if used prior to the appearance of the statement which defines "INPUT".

If "INPUT" is not defined anywhere in the program, the error diagnostic "UE XXXXXX

YYYYYY

AT NNNN'I (Undefined Equivalence) will be generated during Pass 2 and 3 where II XXXXXX" is the I eft-hand symbol (lnd

"yyyyyY" is the undefi ned ri ght-hand symbol. The diaSlnosti'c wi II be generated os many times as an undefined right-hand symbol appears. In any case, "READ" will remain undefined and will appear in the

Pass 3 Symbol Tab I e as

READ

One special circumstance arises if a symbol appears in both a Pass 1 Redefinition or

Duplicate Tag error and a Pass 2 or 3 Undefined Equivalence error. For example suppose the following coding were assembl ed:

READ

JPS RD

*0200

READ, 0

Note that "RDII is never defined and that "READ IJ equival ence statement and as a program ta~J. appears as the left-hand portion of an

During Pass 1, th.e error diagnosti c:

DT READ AT 0200 would be generated and "READ" would not be listed in the Pass 1 Symbol Table.

During Pass 2 or

~~, the error di agnosti c:

U E REA D R D AT 01 00 would be generated but "READ" would remain undefined only until the "READ, 0" statement was encountered. Inasmuch as "READ" is still undefined, the assembler will define it as a tag (giving it the value "0200") and it would appear in the Pass 3 Symbol

Table as

READ

0200

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A statement of the form:

READ

INPUT

'GT

JPS RD will cause the foillowing entries in the Pass 1 Symbol Table (assuming "RD" is undefined when the above statement appears):

GET =

INPUT =GET

READ

INPUT

During Pass 2 or 3, "GET" will be defined, and be listed i-n the Symbol Table with the appropriate octal number to replace the double asterisk. In any case, "READ" and "INPUT" will be treated by the assembler exactly as though the symbol "GET" were being used.

If "G ET" is never defi ned, "READ" and "I NPUT" will also remain undefined.

Finally, there may be only one complex expression or previously defined symbol on a line and it must be terminated with a carriage-return. Thus, the following statement is illegal:

READ

JPS RD

JPS INPUT

No error diagnostic will be immediately produced, but "RD" will be listed in the Pass 1

Symbol Table as HRD" will be listed in the Pass 1 Symbol Table as "RD

**" and any subsequent attempts to define it or use it as, a tag will generate the Redefinition or Duplicate

Tag error messages.

During Pass 2 or

3:, the Undefined Equivalence message will be produced and then "RD" will be defined with a somewhat arbitrary value. Additional error diagnostics may be produced depending on the current value of the Location Counter and the current definition status of the rest of thc~ symbols on the line.

Coding of the foillowing forms:

READ, 0

INPUT

READ

GET

FIND are also illegal and will generate the Redefinition error message.

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3. OPERATOR OR USER CONTROL

The BASC-12 General Assembler is a 2 Pass Assembler that examines the source program and creates a table of symbol address on Pass

1, outputs the assembled binary translation of the source program on Pass 2. An optional third pass is possible during which a symbolic listing (in ASCII Code) is created. Passes

2 and

3 are combined on BASC-12 for DISC systems. Switch Register settings specify which pass the assembler is to undertake and what input and output devices are to be utilized., The following is a detailed description of the Switch Reg i st€~r bit assi gnments:

Bits

0 and 1 indicbte which Pass the assembler is to undertake. Pass

0 is illegal

Pass 1

Pass 2

Pass 3

Bit 0 o

Bit

1 o

Bit 2 is unassigned.

Bit 3 set to

Ill"

CCluses the assemb I er to generate the symbol tab I e at the end of Pass 1.

Bit 4 is unassigned.

Bit 5 set to "1" suppresses page formatting.

Bits 6 and 7 select the input device.

Low Speed ReOider (TTy)

High Speed Reader

None

Cassette

Bit 6 o o

Bit 7 o

1 o

3-1

Bits 8 and 9 select the output device for PCISS 1 and 3. When the non-existent output device is selected, the symbolic listing is destroyed but the error messages are printed.

This is of value to a user assembling a rough program and anticipating many errors.

Low Speed Punch (TTy)

High Speed Punch

Non-existent Device

Non-exi stent Devi ce

Bit 8 o o

Bit o

1 o

Bits 10 and 11 select the output device for Pass 2. When the non-existent output device is selected, the binary is destroyed but the error messages are printed.

Low Speed Punch (TTY)

High Speed Punch

Non-exi si'ent Devi ce

Bit 10 o o

Bit 11 o

1 o

An important "control" the user must not overlook, is the understanding of Instruction Codes, formatting acceptable to the assembler, terminators, directives and special characters.

This knowledge ccm be attained by reading the REFERENCE MANUAL, the DEFINITIONS and PROGRAM DESCRIPTION Sections of this manual.

3-2

4. OPERATIONAL PROCEDURE

1) Load the BASC-12 General Assembler program tape with the

Binary Loader (Refer to the Binary Loader ND41-003 for a detai led description) •

2) Set the Switch Register to 02008 and depress LOAD AR.

Turn on all input and output devices that are intended for use during this assembly.

4) Place i-he paper tape or the cassette storing a source program in the appropriate input device.

Set the pass number (Bits 0 and

11), input device (Bits

6 and

7), pass 2 output device (Bits 10 and 11), and pass 1 and 3 output device (Bits 8 and 9) into the Switch Register. Refer to the

OPERATOR or USER CONTROL Section for a detailed description of this operation.

Depress START.

The source program will now be read and the assembled binary or symbolic translation written Cln the specified device.

NC>TE

The storage buffer of BASC-12 General Assembler is 1024 characters long, exclluding line feeds, blank tape and rub-outs. If a source program i

So contained on paper tape and exceeds the

I im its of the

. storage buffer, it wi

II be necessary to rei oad the sou rce program for each pass of the assemb

I er (return to Step 4 and

5 above and depress

CONTINUE in place of START in Step

6).

4-1

The Magnetic Tape Cassette Unit incorporates circuitry which automatically rewinds the cassette at the end of tape, allowing the assembler to reload the source program via software control.

4-2

5. ERROR DIAGNOSTICS

The error messages generated by the BASC-12 Assembler refer to syntactic errors appearing in the source. A syntactic error will cause a zero to be assembled for the statement in which the error occurs. (This is equivalent to a STOP instruction and will cause the processor to STOP on encountering the incorrectly written instruction when the object program is execut,ed). Numbers in parentheses indicate the pass during which the error diagnostic may occur.

A. IC AT NNNN (ILLEGAL CHARACTER) (1,2,3)

An illegal character was detected during input. The character will appear in the Pass 3

Symbolic Text as

"#".

The illegal character (or

11#") is counted as a blank during assembly.

Illegal character messages'are not counted among the syntactical errors which follow.

B. RD XXXXXX AT NNNN (REDEFINITION) (1)

The symbol" XXXXXX" was encountered as the left-hand portion of an Equivalence

Statement for the second time or was previously used as a program tag. The Equivalence is ignored.

C. DT XXXXXX AT (\INNN (DUPLICATE TAG) (1)

A symbol IIXXXXXX" followed by a comma was encountered and had already been used as a program tag or as the left-hand portion of an equivalence statement. The symbol and comma are ignored.

D. UO XXXXXX AT NNNN (UNDEFINED ORIGIN) (1,2,3)

The symbol" XXXXXX

II was used in a statement preceeded by a

"*" without having been previously defined. An origin specification may consists of any complex expression, but all of the symbols used in the expression must be defined in order for the assembler to reset its Program Location Counter (PLC) to the proper value. It is not possibl e to defer the definition of c:m origin since it is required for Pass 1 as well 'as 2 and 3.

5-1

E. US XXXXXX AT NNNN (UNDEFINED SYMBOL) (2,3)

The symbol

XXXXXX Il was used in the program without ever having appeared in a legal

Equivalence statement or having been used as a program tag. The symbol will also appear in the Pass 3 Symbol Table followed by the double asterisk

(**)0

The symbol is ignored.

F. IR MMMM XXXXXX AT NNNN (ILLEGAL REFERENCE) (2,3)

The Symbol IIXXXXXX Il (with a definition of IIMMMMII) was used as the address of a

Single-Word Memory Reference Instruction and the difference between the Program

Location Counter (PLC) and IIMMMMIl is greater than 6310(778) placing IIXXXXXX Il out of range of the Single-Word MRI. This diagnostic is also produced if the address of an

IJANDF

II instructk)n is less than the PLC (Reverse Reference), if the absolute octal portion of a literal instruction is greater than 778, negative or zero or if any Single-Word instruction attempts to reference itself (MMMM=NNNN=(LC)).

G. DA XXXXXX AT NNNN (DOUBLE ADDRESS) (2,3)

The address of a Single-Word Instruction may consist of only one symbol not connected by plus or minus sign:5. For example, the statE~ment:

JPS A+B is legal; JPS A B is not and wi

II generate the error message II DA B AT NNNN II. The second and succeeding symbols are ignored.

H. UE YYYYYY XXXXXX AT NNNN (UNDEFINED

EQUIVALE~CE)

(2,3)

The symbol II XXXXXX Il appears in the right-hand portion of an Equivalence Statement attempti ng to defi ne YYYYYY and XXXXXX is undefined. lIyyyyyylI wi

II not be defi ned, regardless of the_status of other symbols in the right-hand portion of the Equivalence

Statement. The diagnostic is generated for every undefi ned symbol whi ch appears in the right-hand portion of the statement.

I. UN XXXXXX AT NNNN (UNDEFINED DIRECTIVE) (1,2,3)

An Assembler Directive was encountered which is not defined at all, or is a user defined directive which appears in the program before the appearance of the IIENABLEII Directive.

It is ignored.

J. ST OV XXXXXX AT NNNN (SYMBOL TABLE OVER-FLOW) (1,2,3)

No room could be found in the Symbol Table for the symbol IIXXXXXXII. The current pass is automaticodly terminated. The Symbol Table may be extended by

128 symbols with use of the II EXT EN D II di rective. Th i

S,r however, ri sks destructi on of the Binary

Loader. If the IIEXTENDII directive has altready been used in the source, it will be necessary to alter the program to use fewer symbols.

5-2

K. SYMBOL TABLE DIAGNOSTICS·

Except for the double asterisk, no diagnostics are produced in either symbol table. The double asterisk is used to flag "Undefined Symbols", which, after pass 3, consists of all those symbols for which no definition could be assembled. The message liSE MMMM" which appears on the first line of the Symbol Table (Pass

1 or 3) indicates the first Memory

Address not used for Symbol Table storage. Programs previously loaded into memory which use no locations less than MMMM are ther€~fore not impaired in any way. The number also allows the user to determine how much room is left for additional symbols. (Each symbol requires 4 memory locations for storoge). Maximum Capacity of the symbol table is as follows:

Normal Length (Endi ng at

67768)

355 10

Extended Length (Endi ng at

77768) ::: 48310

These include the Permanent Symbol Table, which contains

8910 symbols. The message itER XXXX" is generated as the last line of the Symbol Table where "XXXX

II is the octal number of syntactical errors occurring in the program during the current Pass. This message appears only ot the end of Pass

1 or Pass 3. Illegal characters do not affect this count.

Finally, it should be noted that the Assembl er does not check for the absence of the

Address element. If a Single-Word Memory Reference is assembled into a location and no address element is provided, reference to location

00008 will be assembled by default.

In any case, propierassembly of a Single-Word Memory Reference Instruction demands that the instruction appears in the first non,-Iabel element on the line. Although not essential for proper assembly, the same rulE~ should be applied to all instructions to minimize the possibility of error and to make the Source Listing easiest to read.

Elements evaluated to a number less than

24008 or greater than

73778 are combined with an inclusive 10gic.aIIOR". This allows micro-programming of the Operate and I/O

Instructions.

5-3

APPENDIX A

INSTRUCTION MNEMONICS IN

ALPHABETICAL ORDER

OCTAl

CHSR

CLR

CLR J

CLR K

CLR JK

CLR 0

CMP

CMPJ

CMPK

CMP JK

CMPO

CRDT

CSBT

CSET

CSFM

ADDL

ADJ

ADR J

ADR K

ADSJ

ADS K

AJK J

AJK K

AJK JK

ANDF

ANDJ

AND K

ANDJK

ANDL

CCLF

CHSF

1200

1300

21XX

0141

0101

0121

1410

1510

1610

1710

1450

1420

1520

1620

1720

1460

0144

0130

0110

0104

22XX

4400

1122

1222

1124

1224

1120

1220

1320

20XX

1100

DESCRIPTION

Add Literal to J

Add to J

J ·to J

K to K

J to J

K to K

K to J

K to K

K to J, K

AND wi th J, ForwGrd

AND J, K into J

AND J, K into K

AND K, J into K, J

AN D Uteral with J

C I ear all Cassette FI ags (TWIO)

High Speed Forward to EOT (TWIO)

High Speed Reverse to BOT (TWIO)

Clear Flag Register

Clear J

Clear K

Clear J, K

Clear Overflow Register

Compl ement Flag Regi ster

Complement J

Complement K

Complement J, K

Complement Overflow Register

Read Cassette Tape to J (TWIO)

Skip if Cassette at BOT (TWIO)

Skip if Cassette at EOT (TWIO)

Skip if Cassette Read Fi I e Mark (TWIO)

A-l

TIMING

1 cy

2 cy

1 cy

2 cy

1 cy

J.1S

1 cy

J.1S

OP OCT .AIL

- - -

CSLCT 1

7601

CSLCT2

7602

CSLCT3 7604

CSNE

0122

CSPF

0102

CSRR

CSTR

0142

0124

0152

CSWR

CWFM

CWRT

DIV

0151

0154

1001

DSZ

3000

EXJR

1103

EXJKRS

1303

EXKS

HIF

HIR

HIS

HLP

HRF

HOP

1203

7421

7422

7424

7433

7423

7431

HOS

INC

INC K

7434

1504

1604

·INC JK

1704

IOFF

1003

IONA

1005

IONB

IONH

1006

1004

IONL

ISZ

JMP

JPS

LDJ

1007

3400

6000

6400

5000

7721

LDJK

LDREG

LJIPB

LJ KFRS

LJST

LJSW

LKFJ

LJFR

LKFS

LRFJ

7720

7722

1302

1011

1010

1204

1102

1202

1101

DESCRIPTION

Place Cassette 1 On-Li ne

Place Cassette 2 On-Line

Place Cassette 3 O'n-Line

Skip if No- Error Cassette (TWIO)

Space Cassette Forward to Fi I e Mark (TWIO)

Skip if Cassette Read Ready (TWIO)

Skip if On-Line Cossette Ready (TWIO)

Skip if Cassette Write Ready (TWIO)

Cassette Write File Mark (TWIO)

Cassette Write Transfer (TWIO)

Divide J and K by R

Decrement Memory and Skip

Exchange J and R

Exchange J

K with

Exchange K and S

H S Reader Fetch

CLR Flag; Read HS Buffer

Skip if H S Reader Reader

H S Punch Load and Punch

H S Reader Read-Fetch

HS Punch On

Skip if HS Punch Ready

Increment

Increment K

Increment

Disable all Interrupt Levels

Enab I e Interrupt L1evel s H

& A

Enable Interrupt Levels H & B

Enable Interrupt Level H Only·

Enable All Interrupt Levels

Increment Memory and Skip

Unconditional Jump

Jump Subroutine

Load J

Load JPS Reg to J/INT reg to

Load JPS Reg From

INT reg to K

Set JPS and INT Status Bits

Load J

K from R/' S

Load J from Status Regi ster

Load J from Switches

Load K from J

Load J from R

Load K from S

Load R from J

·A-2

TIMING

1 cy

5 JJs

11 JJs

2 cy

1 cy

2 cy

1 cy

2 cy

1 cy

3 JJs

3 JJS

3 JJs

1 cy

OP OCT ,L~L

- - -

LRSFJK

LSFK·

1301

1201

MPY

1000

NADR J

1132

NADR K 1232

NADSJ

1134

NADS K

1234

NAJK J 1130

NAJK K 1230

NAJK JK

1330

NEG J

1524

NEG K

1624

NEG JK

1724

NSBR J 1133

NSBR K

1233

NSBS J

1135

NSBS K 1235

NSJK J

1131

NSJK K 1231

PIOF

1600

PION

RFOV

1500

1002

ROTC> J

1160

ROTD K

1260 .

ROTD JK 1360

SBJ

SBR J

4000

1123

SBR K

SBS J

SBS K

SET

SET J

SET K

SET JK

SET 0

SFTZ J

1223

1125

1225

1430

1530

1630

1730

1470

1140

SFTZ K 1240

SFTZ JK 1340

SIN J

1506

SIN K'

SIN JK

SIP J

1606

1706

1502

SIP K

SIP JK

1602

1702

DESCRIPTION

Load R, S from J, K

Load S from K

Multiply J by K

-(R + J)' to J

-(R + K) to K

-(S + J) to J

-(S+ K) to K

-(J + K ) to J

-(J + K) to K

-(J + K) to J, K

Negate J

Negate K

Negate J, K

J-R to J

K-R to K

J-S to J

K-S to K

K-J to J

K-J to K

Powerfai I system off

Powerfai I system on

Read Flag and Overflow Bits from J

Rotate J Left N

Rotate K Left N

Rotate J, K Left N

Subtract J

R-J to J

R-K to K

S-J to J

S-K to K

Set Flag Register

Set J to -1

Set K to -1

Set J, K to -1

Set Overflow Register

Shift J Left N

Shift K Left N

Shift J, K Left N

Skip if J Negative

Skip if K

NegativE~

Skip if J, K Negative

Skip if J Positive

Skip if K Positive

Skip if J, K Positive

A-3

TIMING

1 cy

10. 75

'1 cy

1 cy

1 cy +

1 cy

2 cy

1 cy

1 cy +

1 cy

1 cy lcy

1 cy

1 cy l-'s

OP DESCRIPTION

SIZ

SIZ J

1405

1505

SIZ K

SIZ JK

SIZ

SJK J

1605

1705

1445

1121

SJK K

SKIP

SKPL

TWSMK

TWSTJ

1221

6002

1440

SMJ

SNZ

SNZ J

SNZ K

SIZ'JK

2400

1401

1501

1601

1701

1441

SNZ

STJ

STOP

SUBL

TCP

5400

OOXX

23XX

7413

7401

TIF

TIR

TIS

7402

7404

7411

TOC

TOP

'TOS

TWADJ

7412

7414

0400

TWADK 0450

TWDSZ

0300

TWISZ

TWJMP

TWJPS

0340

0600

0640

TWLDJ

TWLDK

TWSBJ

TWSBK

TWSMJ

0500

0510

0400

0410

0240

0250

TWSTK

XCT

0540

0550

7000

Skip if Flag Zero

Skip if J

Skip if K

Skip if J, K

Skip if Overflow Register

J-K to J

J-K to K

Unconditional Skip (Jump)

Skip if Power Low

Skip if Memory Not Equal J

Skip if Flag One

Skip if J Not Equcd Zero

Skip if KNot EquClI Zero

Skip if

J, K Not Equal Zero

Skip if Overflow Register

One

Store J

Stop Execution

Subtract

Li tera I from J

Clear TTY Flag, Print-Punch

TTY Keyboard-ReCider Fetch

TTY Load Keyboard into J

Skip if TTY Keyboard Ready

TTY Clear Flag

TTY Clear flag; Print-Punch

TTY Skip if Printer-Punch Ready

Two Word Add J

Two Word Add K

Two Word Decrement Memory and Skip

Two Word Increment Memory and Skip

Two Word Uncondi'tional Jump

Two Word Jump Subroutine

Two Word Load J

Two Word Load K

Two Word Subtraci" J

Two Word Subtraci" K

Two Work Skip if J\t\emory Not Equal J

Two Work Skip if ,J\t\emory Not Equal K

Two VYord Store J

Two Word Store K

Execute Displaced Instruction

II@II t::ldds one cycle to any memory reference instruction.

TIMING

1 cy

2 cy

1 cy

3 cy

2 cy

3 cy

3 J.lS

3 J.ls

3 J.lS

3 J.ls

3 J.lS

3 J.ls

3 cy

APPENDIX B

INSTRUCTIONS IN OCTAL

SEQUENCE

OCTAL

OOXX

0101

0102

0104

0110

0121

0122

0124

0130

0141

0142

0144

0151

0152 .

0154

0240

0250

0300

0340

0400

0410

0440

0450

0500

0510

0540

0550

0600

0640

1000

CSWR

CWRT

TWSMJ

TWSfv\K

TWDSZ

TWISZ

TWSBJ

TWSBK

TWADJ

TWADK

TWLDJ

TWLDK

TWSTJ

TWSTK

TWJ!v1P

TWJPS

MPY

STOP

CHSF

CSPF

CSFM

CSET

CHSR

CSNE

CSTR

CSBT

CCLF

CSRR

CRDT

CWFN\

SYMB,OL

DESCRIPTION

Stop Execution

Cassette High-Speed Forward EOT (TWIO)

Cassette Space Forward to File Mark (TWIO)

Cassette Skip on File Mark (TWIO)

Cassette Skip if EC)T (TWIO)

Cassette High-Speed Reverse BOT (TWIO)

Cassette Skip No-Error (TWI 0).

Cassette Skip if On-Line Tape Ready (TWIO)

Cassette Skip if BC)T (TWIO)

Cassette Clear All Flags (TWIO)

Cassette Skip if Read Ready (TWIO)

Cass ette Read to J (TWIO)

Cassette Write File Mark (TWIO)

Cassette Skip if Write Ready (TWIO)

Cassette Write Transfer (TWIO)

Two Word Skip if i\~emory

Not Equal J

Two Word Skip if i\~emory

Not Equal K

Two Word Decrement and Skip

Two Word Increment and Skip

Two Word Subtract J

Two Word Subtract K

Two Word Add J

Two Word Add K

Two Word Load J

Two Word Load K

Two Word Store J

Two Word Store K

Two Word Unconditional Jump

Two Word Jump Subroutine

Multiply J by K

1~-1

TIMING

1 cy

3 cy

2 cy

10.75~s

OCTAL

1202

1203

1204

1220

1221

1222

1223

1224

1225

1230

1231

1232

1233

1234

1235

1130

1131

1132

1133

1134

1135

1140

1160

1200

1201

1001

1002

1003

1004

1005

1006

1007

1010

1011

1100

1101

1102

1103

1120

1121

1122

1123

1124

1125

SYMB<)L

DESCRIPTION

DIV

RFOV

IOFF

IONH

IONA,

IONB

IONL

LJSW

LJST

ANDJ

LRFJ

LJFR

Divide J and K by R

Read Flag, Overflow from J

Disable All Interrupt Levels

Enable Level H On Iy

Enable Interrupt Levels H

Enable Interrupt Levels H & B

Enable All Interrup'r Levels

Load J from Swi tches

Load J from Status Register

And J, K into J

Load R from J

Load J from R

EXJR

AJK J

SJK J

ADR

Exchange J and R

K to J

J - K to J

J to J

SBR J

ADSJ

ROTD J

R ... J to J

J to J

SBS J

S - J to J

NAJKJ -(J

K) to

NSJK J

NADR J

NSBR J

NADSJ

NSBS J

SFTZ

K - J to J

-(R

J) to J

J - R to J

-(5

J) to J

J - S to J

Shift J Left N

Rotate J Left N

AND K

LSFK

LKFS

EXKS

LKFJ

AJK K

SJK K

ADR K

SBR K

ADS K

SBS K

NAJK K

AND J, K into K

Load S from K

Load K from S

Exchange K and S

Load K from J

K to K

J - K to K

K to K

R - K to K

K to K

S - K to K

-(J

K) to K

NSJK K K - J to K

MADR L -(R

K) to K

NSBR K K - R to K

NADSK -(S

K) to K

NSBS K K - S to K

1~-2

TIMING

1 cy

11 tJs

1 cy

,1 cy

1 cy

OCTAL

1401

1405

1410

1420

1430

1440

1441

1445

1450

1460

1470

1500

1501 .

1240

1260

1300

1301

1302

1303

1320

1330

1340

1360

1502

.1504

1505

1506

1510

1520

1610

1620

1624

1630

1701

1702

1704

1524

1530

1600

1601

1602

1604

1605

1606

DESCRIPTION

SFTZ K

Shift K Left N

ROTD K Rotate K Left N

ANDJI<

AND J, K into K,-'

LRSFJK Load R, S from J, K

LJ KFRS Load J, K from R, S

EXJKRS Exchange J, K wi th R, S

AJ K .J K

K to J, K

NAJK JK -(J

K) to J, K

SFTZ JK Shift J, K Left N

ROTC> JK Rotate J, K Left N

SNZ Skip if Flag Register One

SIZ

CLR

CMP

SET

SKPL

Skip if Flag Register Zero

Clear Flag Register

Compl ement Flag Regi ster

Set Flag Register to One

Skip on Power Low

SNZ 0

SIZ c)

CLR ()

Skip if Overflow Register One

Skip if Overflow Register Zero

Clear Overflow Register

CMPO Complement Overflow Register

SET C)

Set Overflow Register to One

PION Powerfai I System

()n

SNZ

SIP J

INC

SIZ J

SIN JI

Skip if J Not Equal Zero

Skip if J Positive

Increment J

Skip if J

Skip if J Negative

CLR .J

CMPJ

NEG J

SET J

PIOF

SNZ K

SIP K

INC K

SIZ K

SIN K

CLR K

Clear J

Complement J

Negate J

Set J to

-1

Powerfai I System

()ff

Skip if KNot Equo:1 Zero

Skip if K Positive

Increment K

Skip if K

Negativ~

Clear K

CMPK

NEG K

SET I<

Complement K

Negate K

Set K to

-1

SNZ JK Skip if J, K Not Equal Zero

SIP JK

Skip if J, K Positive

INC .JK Increment

B-3

TIMING

1 cy

.1 cy

1 cy

OCTAL

7422

7431

7432

7433

7434

·7601

7602

7604

7720

7721

7722

6400

7000

7401

7402

7404

7411

7412

7413

7414

7421

1705

1706

1710

1720

1724

1730

20XX

21XX

22XX

23XX

2400

3000

3400

4000

4400

5000

5400

6000

6002

SYMBOL

- - -

DESCRIPTION

SIZ JK

SIN JK

Skip if J, K

Skip if J, K Negative

CLR .JK

Clear J, K

CMP JK

Complement J, K

NEG JK Negate J, K

Set J, K to -1

SET JIK

ANDF

ANDL.

AD.DL.

SUBL

SMJ

DSZ

AND with J, Forword

AND J Literal

ADD J Literal

SUB TRACT J Li tera

Skip if J not Equal Memory

Decrement Memory and Skip

Increment Memory and Skip

ISZ

SBJ

ADJ

Subtract from J

Add to J

TOC

TOP

TCP

TOS

HIF

HIR

HOP

HOL

HLP

LDJ

STJ

JMP

SKIP

JPS

XCT

TIF

TIR

TIS

Load J

Store J

Unconditional Jump

Unconditional Skip

Jump Subroutine

Execute

Di splaced Instruction

TTY Keyboard-Reader Fetch r(Y Keyboard Into J

TTY Skip if KeyboClrd Ready

TTY Clear Flag

TTY Clear Flag, Print-Punch

TTY C lear Flag, Print-Punch

TTY Skip if Printer-Punch Reader

H S Reader - Fetch

H S Reader - CLR Flag, Read Buffer

H S Punch - Punch On

:HS Punch - CLR Flag, Load Buffer

H S Punch - Load and Punch

HOS

CSLClrl

H S Punch - Skip if punch ready

Cassette - Unit 1 C)n-Line

CSLCT2

Cassette - Unit 2 C)n-Line

CSLCT3

Cassette - Unit 3 ()n-Line

LDREC;

LDJK

Load JPS Reg from J, INT Reg from K

Load JPS Reg to J, INT Reg to K

LJIPB Set JP S and I NT Sl'atus Bits

"@" odds one cycle to any memory reference instruction.

TIMING

1 cy

2 cy

1 cy

1 +n

1 cy

2 cy

1 cy

B-4

APPENDIX C

ASCII CHARACTER SET

CHARACTER

X y

ASCII CODE

301

302

~303

304

305

306

307

310

311

312 '

322

323

324

325

326

327

330

331

332

313

314

315

316

317

320

321

CHARACTER

+

Space

Tab

Line Feed

Form Feed

Carriage Return

Rubout

!C-l

ASCII CODE

270

271

244

252

253

254

255

256

257

273

260

261

262

263

264

265

266

267

275

240

211

212

214

215

377

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