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2024-03-02: The wiki ran out of disk space, so things were not working. This has been resolved by adding another 5GB of quota ;-) Thanks to Tim Lindner for reporting the issues.
2020-05-17: If a page gives you an error about some revision not being found, just EDIT the page and the old page should appear in the editor. If it does, just SAVE that and the page should be restored. OS-9 Al (talk) 12:22, 17 May 2020 (CDT)
The Structure of I-Code
The 'I' in I-Code stands for Intermediate. Intermediate code is code that is a step between interpreted source statements and fully compiled machine code. Typically, intermediate code uses tokens to represent the instructions to be executed. Basic09 I-Code goes a step further by re-arranging the source code instructions in post-fix notation (also known as Reverse Polish Notation) order.
The tokens used by Basic09 are a single byte ranging from $00 to $FF. See I-Code Token List
Terms Used
| Vector | 1 Dimensional Array | |
|---|---|---|
| Table | 2 Dimensional Array | |
| Matrix | 3 Dimensional Array | |
| Variable Declaration Table (VDT) | Symbol Table | |
| Data Storage Allocation Table (DSAT) | Definition Area |
Module Format
Basic09 I-Code modules use the same module format as any other OS-9 executable module. However, I-Code modules include optional header extensions not included in other types of memory modules. They also include two very important tables specific to I-Code modules.
Modules are divided into the following sections:
Module Header
| Description | Size | Note |
|---|---|---|
| Module Header Space (Sync Bytes) | INTEGER | Value always $87CD |
| Total Procedure Block Size | INTEGER | Total size of the module, including CRC and header |
| Module Name Offset | INTEGER | Offset address in the header of the Procedure Name Beginning |
| Module Type/Language | BYTE | Value always $22; Sub-Routine/Basic09 I-Code |
| Module Attributes/Revision | BYTE | Value always $81; Re-Entrant,Re-Locatable Object/Revision=1 |
| Module Header Parity | BYTE | Last required module header entry; optional header extensions follow |
| I-Code Area Address | INTEGER | Offset address of the I-Code instructions |
| Runtime Variable Storage Size | INTEGER | Total data memory size for the module |
| Symbol Table Address | INTEGER | Offset address of the VDT |
| Description Area Address | INTEGER | Offset address of the DSAT |
| Procedure Link Storage Offset | INTEGER | Beginning of Named Subroutine Storage in Data Memory |
| First Data Statement Address | INTEGER | Offset address of the first element of the first data statement |
| First Executable Statement Address | INTEGER | Value always $0000; (Unused, Possible association: <dex> token. See 2) |
| Procedure Status | BYTE | Value always $80; (I do not know what this BYTE is used for.) |
| Procedure Name Size | BYTE | |
| Procedure Name Beginning | Procedure Name Size BYTEs | |
| Edition Number | BYTE | Always the first byte after the Module Name. This BYTE is actually the first byte of I-Code, at the I-Code Area Address location, and not part of the header. See 1 |
NOTES
1: The OS-9 Level II Manual describes the Edition byte in Chapter 6. System Command Descriptions,
under the Ident command on page 6-52,53.
The OS-9 Level I Manual Set includes this information in the OS9 Commands Manual, Chapter 6. System
Command Descriptions, Ident command, page 87.
2: the <dex> token is $3C, and is defined in the Basic09 header file:
T.DEXC rmb 1 Direct execution
There is also a Basic09 error:
48: Unimplemented routine
While I have never run into this error in any procedure I have written or decoded, it still exists. Is it possible that Basic09 originally had code that allowed its developers to insert assembly language instructions directly into the I-Code? I can see where it would have been useful, and I can see where that code would be in comments in the original source, if the authors didn't want that included in the final compile.
I-Code Area
This is where all of your instruction statements are stored in tokenized post-fix notation form. While there is no requirement to do so, it is typical to see this area terminated with a END ($39) token followed by a line termination token ($3F).
Basic09 allows you to place TYPE, DIM and PARAM statements anywhere in the source code. When Basic09 loads your source, it immediately converts the source to tokenized form. In doing so, it compiles a complete list of your program variables as it loads. It also compiles a complete list of all line references. Line references are not the numbers you place at the beginning of a line. This list is created from all GOTO ($20) and GOSUB ($22) (including ON ERROR GOTO, and ON <expr> GOTO/GOSUB), RESTORE <lref> ($31) and IF-THEN <lref> ($10-$45) statements. In addition, there are internal offset branch tokens, including invisible goto (<ivgt> $55), the line reference token ($3B), ELSE ($11), ENDWHILE ($16) and ENDLOOP ($1A).
Description Area
This is the first of the two variable-related tables in I-Code modules. In reality, this section contains the shape data for all variables more complex than a simple atomic type. The form the shape data takes is specific to the type of variable being described. The most simple form is:
offset - size (both INT-size)
Offset is the data memory location of the variable, and size is the length of the variable. This form is used, by itself, to describe non-array STRING and record variables. All other entries (except TYPE shape data) begin with these two fields, and add extra fields to describe the variable. These variables are the array variables, and include the following fields (all INT-size):
- first element size (all arrays)
- second element size (all table and matrix arrays)
- third element size (all matrix arrays)
- element length (all STRING and record arrays)
TYPE statement data is different. First, all complex data forms included in the TYPE are listed immediately before the shape data for the TYPE. In these cases, the offset is not a data memory address, but the offset within the record for that variable. The form the TYPE shape data takes is as follows:
size (INT); unknown use (INT or 2 BYTEs); first field (single BYTE); second field (INT); ... <nth> field (INT)
TYPEs within TYPEs adds a new level of complexity. Before the shape data that includes a field DIM'd as a record, the shape data for that record TYPE is defined. as well as any other complex variables defined in that TYPE occurring before its shape data.
At the end of this table is another "3-byte" structure. However, this one is reversed, so it is <INT>-<BYTE>, and each can be viewed as separate from the other. The INT is the Total Program Variables count. This number includes all DIM'd, PARAM'd and TYPE'd variable names. Yes, TYPE REG= means REG is counted as a variable. This number also includes all variables defined by use.
The BYTE, in every module I have seen except one, holds the value $03. In the one case, it held the value $04. I no longer have the module that contained $04, and I have never understood what this byte is used for. It is the final byte before the beginning of the Symbol Table.
Symbol Table
This is the second of the two variable-related tables in I-Code modules. The first thing you will notice is that this table is almost entirely 3-byte structures, similar to the ones found in the I-Code area. The difference here is the number of different tokens for defining variables according to their atomic type, as well as STRINGs, records and arrays. Parameter variables are listed here, following the program variables, and after that comes the named subroutine (external procedure/object-code subroutine) list.
Sub-routine entries begin with the $A0 token, followed by the data memory offset of the pointer to that subroutine, and the text of the name of the subroutine (last character hi-bit set, same as the module name in the header of the module). The Procedure Link Storage Offset in the header points to the first memory location that holds the pointer to the first subroutine named in this section of the list. For all other VDT tokens, see the Symbol Table Tokens.
The offset field in the program variables and parameter variables portion of the list points to one of three places.
- In all atomic record field entries ($40-$43) the offset is the position within the record of that field. The atomic type determines the size.
- In all atomic variables ($60-$63), the offset is the data memory location of that variable, and the size is determined by the type.
- In all atomic parameter variables ($80-$83), the offset is the data memory location of that variable, and the size is four BYTEs.
- In all other variable types, the offset is relative to the beginning of the DSAT.
The data size for each parameter variable, whether atomic or not, is four BYTEs. That is the difference between one parameter's data memory address and the next one. The DSAT contains the shape data for the more complex variables, but the data memory pointer in a called procedure is a 4-byte pointer.
CRC
All OS-9 memory modules end with a 3-byte CRC. I have not seen a utility for re-calculating a module's CRC.
Instruction I-Code
In this section I will describe the various structures used in Basic09 coding, including the looping constructs, conditional statements, and the use of literals (constants).
Internal Structures
As you have seen, I-Code makes use of 3-byte structures for variable references. It uses them as well for branch references (including line references). They use the form:
token - offset
where token is any valid Basic09 branch or variable token, and offset is a INTEGER-size value. All addressing in I-Code is relative. Branch references are relative to the beginning of the I-Code area, and variable reference offsets are relative to one of the following:
- BYTE, INTEGER, REAL and BOOLEAN references (token values $80-$83): data memory offset relative to the beginning of data memory.
- STRING references (token value $84): DSAT offset relative to the beginning of the Description area.
- all other token values in the I-Code area: VDT offset relative to the beginning of the Symbol Table.
Data Memory Map
0 $15|$16 +----------------------+-----------------+--------------+--------------------+ |reserved by RunB |program variables|parameter list|named procedure list| +----------------------+-----------------+--------------+--------------------+
The first $16 (22) bytes of the data space is reserved for use by RunB. Following this are the program variables, the parameter list, and the named procedure list.
Structures
FOR/NEXT
The FOR/NEXT loop structure is the most complex in terms of I-Code. It contains the most fields of any other loop structure in Basic09.
FOR R0122= 1 TO 8 \ 13 82 07D3 53 8D 01 CB 46 07D8 8D 08 CB 55 006A 3E FOR R0122 := <bc> 1 <flt1> TO <bc> 8 <flt1> <ivgt> \
13 is the FOR token
82 is the REAL type token
07D3 is the data memory offset for a REAL variable named R0122, which occupies 5 bytes beginning at that location
53 is the = assignment operator token
8D is the <bc> (byte constant) token, and is associated to the following numeric value
01 is the value 1
CB is the <flt1> (float top of stack) token
46 is the TO token
07D8 is the data memory offset for a temporary variable used to store the following value
8D is the <bc> (byte constant) token, and is associated to the following numeric value
08 is the value 8
CB is the <flt1> (float top of stack) token
55 is the <ivgt> (invisible goto) token
006A is the module offset to branch to when the condition fails
3E is the \ instruction terminator. This character allows stacking of mutiple statements on a single line in the source code. Many times, these occur because the author included line comments, such as \REM populate array. Usually, this will be the <eol> (3F) terminator
NEXT R0122 14 02 07D3 07D8 0000 004C 3F NEXT R0122 TO STEP <ivgt> <eol>
14 is the NEXT token
02 determines REAL or INTEGER, with or without a STEP value.
00 INTEGER 01 INTEGER w/STEP 02 REAL 03 REAL w/STEP
07D3 is the data memory address for R0122
07D8 is the TO variable
0000 is the STEP variable, if included in the FOR statement. In every FOR loop that does not include a STEP value, this integer is 0
004C <ivgt> pointing to the beginning of the first instruction within the loop. Note the lack of a $55 token. This is the only condition where a <ivgt> does not have the token
3F is the <eol> (end of instruction/line) token
WHILE/ENDWHILE
WHILE NOT(EOF(#B0028)) DO 15 80 0329 BE CD 55 0DE7 48 3F WHILE B0028 EOF() NOT() <ivgt> DO <eol>
15 is the WHILE token
80 is the BYTE atomic type
0329 is the data memory address of a variable named B0028
BE is the EOF() function token
CD is the NOT() function token
55 is the <ivgt> token
0DE7 is the offset to branch to when the condition fails
48 is the DO token
3F is the <eol> token
ENDWHILE 16 0CBF 3F ENDWHILE <offset> <eol>
16 is the ENDWHILE token
0CBF is the offset address of the WHILE statement
3F is the <eol> token
REPEAT/UNTIL
LOOP/ENDLOOP
This is the most simple loop structure in Basic09. The EXITIF-THEN/ENDEXIT construct is the only way to exit this loop.
| $19 | LOOP |
|---|---|
| $1A <offset> | ENDLOOP |
<offset> is the address of the first instruction inside the loop
Conditional
IF-THEN <lref>
IF-THEN/ENDIF
IF-THEN/ELSE/ENDIF
EXITIF-THEN/ENDEXIT
Literals
Basic09 does not have named constants. Because of this, all "constants" in Basic09 are of the literal variety. If you want to use variables as constants, you may do so, but it is up to you to ensure that the variables being used as constants are not being modified. To help with this, the recommended form of variable naming is to use a lowercase 'c' as the first character of the variable name (e.g. cMyConstant or cMYCONSTANT).
| Type | Token | Value | |
|---|---|---|---|
| BYTE | $8D | numeric literal from 0 to 255/-128 to 127 | |
| INTEGER | $8E | numeric literal from -32768 to 32767 | |
| REAL | $8F | numeric literal in the range of a Basic09 REAL | |
| Hexadecimal Integer | $91 | hexadecimal value from $0000 to $FFFF | |
| BOOLEAN | $BC = TRUE | ||
| $BD = FALSE | |||
| STRING | $90 = beginning bound of string | string of text | |
| $FF = ending bound of string |
About GOTO, GOSUB and <lref> tokens
There are two types of these identified in the Basic09 header. They are identified as bound and unbound. The bound versions are the ones that occur in packed I-Code. I believe the unbound versions are used when Basic09 loads your source into the workspace and converts it to I-Code initially. I think it works something like this:
As Basic09 loads the source, it is replacing all keywords, function names and other items with tokens. As it comes across GOTO, GOSUB and <lref> identifiers (THEN <lnum>, RESTORE <lnum>, ON ERROR GOTO <lnum>, ON <expr> GOTO/GOSUB <lnums>), it searches the table it creates to hold branch references. If the line number has already been identified (existed at the beginning of a line and the address was resolved), that one is skipped and the identifier is flagged with the bound token. If that line number has not yet occurred in the source, then that identifier is flagged with the unbound token until that line number occurs at the beginning of a source statement, at which time the identifier is flagged with the bound token. Any identifiers not resolved when the source is loaded results in an error.
This is why the line number at the beginning of a line can disappear from your I-Code. Without an identifier to point to it, that reference does not exist in packed I-Code.
File Access Mode Tokens
READ+WRITE = UPDATE
| 80 | DIR | ||
|---|---|---|---|
| 01 | READ | 81 | READ+DIR |
| 02 | WRITE | 82 | WRITE+DIR |
| 03 | UPDATE | 83 | UPDATE+DIR |
| 04 | EXEC | 84 | EXEC+DIR |
| 05 | READ+EXEC | 85 | READ+EXEC+DIR |
| 06 | WRITE+EXEC | 86 | WRITE+EXEC+DIR |
| 07 | UPDATE+EXEC | 87 | UPDATE+EXEC+DIR |
I-Code Instruction Variable Tokens
I have never liked the usage of MIRROR in this instance. I have no better way to describe these tokens at this time. I referred to them as mirror tokens, because in some instances they act as a duplicate of the variable, such as in the case of a:=a+1. Both 'a' variables refer to the same variable, but in the I-Code, each has a separate token, and with the exception of 80-84 (in the instruction area) point to the VDT. 80-83 in the instruction area point to data memory addresses, and 84 points to the DSAT.
| VARIABLE | FIELD | PARAMETER | ||||
|---|---|---|---|---|---|---|
| TYPE | TOKEN | MIRROR | TOKEN | MIRROR | TOKEN | MIRROR |
| BYTE | 80 | F2 | F6 | 89 | 85 | F2 |
| INTEGER | 81 | F2 | F6 | 89 | 85 | F2 |
| REAL | 82 | F2 | F6 | 89 | 85 | F2 |
| BOOLEAN | 83 | F2 | F6 | 89 | 85 | F2 |
| STRING | 84 | F2 | F6 | 89 | 85 | F2 |
| RECORD | 85 | F2 | F6 | 89 | 85 | F2 |
| VECTOR | 85/86 | F3 | F7 | 8A | 85/86 | F3 |
| TABLE | 85/87 | F4 | F8 | 8B | 85/87 | F4 |
| MATRIX | 85/88 | F5 | F9 | 8C | 85/88 | F5 |
Symbol Table Tokens
| FIELD | VARIABLE | PARAMETER | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| TYPE | SIM | VEC | TAB | MAT | SIM | VEC | TAB | MAT | SIM | VEC | TAB | MAT |
| BYTE | 40 | 48 | 50 | 58 | 60 | 68 | 70 | 78 | 80 | 88 | 90 | 98 |
| INTEGER | 41 | 49 | 51 | 59 | 61 | 69 | 71 | 79 | 81 | 89 | 91 | 99 |
| REAL | 42 | 4A | 52 | 5A | 62 | 6A | 72 | 7A | 82 | 8A | 92 | 9A |
| BOOLEAN | 43 | 4B | 53 | 5B | 63 | 6B | 73 | 7B | 83 | 8B | 93 | 9B |
| STRING | 44 | 4C | 54 | 5C | 64 | 6C | 74 | 7C | 84 | 8C | 94 | 9C |
| RECORD | 45 | 4D | 55 | 5D | 65 | 6D | 75 | 7D | 85 | 8D | 95 | 9D |
Keyword Tokens
| 04 | DATA | 05 | STOP | 06 | BYE | 39 | END | ||
|---|---|---|---|---|---|---|---|---|---|
| 07 | TRON | 08 | TROFF | 09 | PAUSE | 0A | DEG | 0B | RAD |
| 0C | RETURN | 0D | LET | 0F | POKE | ||||
| 10 | IF | 11 | ELSE | 12 | ENDIF | ||||
| 13 | FOR | 14 | NEXT | 15 | WHILE | 16 | ENDWHILE | ||
| 17 | REPEAT | 18 | UNTIL | 19 | LOOP | 1A | ENDLOOP | ||
| 1B | EXITIF | 1C | ENDEXIT | ||||||
| 1D | ON | 1E | ERROR | 20 | GOTO | 22 | GOSUB | ||
| 23 | RUN | 24 | KILL | 25 | INPUT | 26 | |||
| 27 | CHD | 28 | CHX | ||||||
| 29 | CREATE | 2A | OPEN | 2B | SEEK | 2C | READ | 2D | WRITE |
| 2E | GET | 2F | PUT | 30 | CLOSE | 32 | DELETE | 31 | RESTORE |
| 33 | CHAIN | 34 | SHELL | 35 | BASE 0 | 36 | BASE 1 |
Secondary Keyword Tokens
| 45 | THEN | 46 | TO | 47 | STEP | 48 | DO | 49 | USING |
|---|
Punctuation Tokens
| 4B | , | 4C | : | 4D | ( | 4E | ) | 51 | ; |
|---|
String Length Value Tokens
| 4F | [ | 50 | ] |
|---|
Assignment Operator Tokens
| 52 | := | 53 | = |
|---|
File Mode and Path Operator Tokens
| 4A | : | 54 | # |
|---|
Internal Tokens
| 0E | <cva> | 3B | <blr> | 3C | <dex> | 3E | \ | 3F | <eol> | 55 | <ivgt> |
|---|---|---|---|---|---|---|---|---|---|---|---|
| C8 | <fix1> | C9 | <fix2> | CA | <fix3> | CB | <flt1> | CC | <flt2> |
Numeric Function Tokens
| 97 | ERR() | 98 | MOD() | 99 | MOD() | 9A | RND() | ||
|---|---|---|---|---|---|---|---|---|---|
| 9B | PI | 9D | SGN() | 9E | SGN() | 9F | SIN() | ||
| A0 | COS() | A1 | TAN() | A2 | ASN() | A3 | ACS() | A4 | ATN() |
| A5 | EXP() | A6 | ABS() | A7 | ABS() | A8 | LOG() | A9 | LOG10() |
| AA | SQRT() | AB | SQR() | AC | INT() | AD | INT() | AE | FIX() |
| AF | FIX() | B0 | FLOAT() | B1 | FLOAT() | B2 | SQ() | B3 | SQ() |
Screen/Print Function Tokens
| 96 | POS() | C7 | TAB() |
|---|
File and Other Function Tokens
| 92 | ADDR() | 93 | <addr> | 94 | SIZE() | 95 | <size> |
|---|---|---|---|---|---|---|---|
| BE | EOF() | B4 | PEEK() |
String Function Tokens
| 9C | SUBSTR() | BF | TRIM$() | C0 | MID$() | C1 | LEFT$() | C2 | RIGHT$() |
|---|
String-to-Number Function Tokens
| B6 | VAL() | B7 | LEN() | B8 | ASC() |
|---|
Number-to-String Function Tokens
| C3 | CHR$() | C4 | STR$() | C5 | STR$() | C6 | DATE$ |
|---|
Logical Operator Tokens
| B5 | LNOT() | B9 | LAND() | BA | LOR() | BB | LXOR() |
|---|
Boolean Function Tokens
| CD | NOT() | CE | - | CF | - | D0 | AND | D1 | OR | D2 | XOR |
|---|
Comparison Operator Tokens
| D3 | > | D4 | > | D5 | > | ||
|---|---|---|---|---|---|---|---|
| D6 | < | D7 | < | D8 | < | ||
| D9 | <> | DA | <> | DB | <> | DC | <> |
| DD | = | DE | = | DF | = | E0 | = |
| E1 | >= | E2 | >= | E3 | >= | ||
| E4 | <= | E5 | <= | E6 | <= |
Math Operator Tokens
| E7 | + | E8 | + | E9 | + |
|---|---|---|---|---|---|
| EA | - | EB | - | ||
| EC | * | ED | * | ||
| EE | / | EF | / | ||
| F0 | ^ | F1 | ** |
I-Code Token List
| Token | Name | Used In | Description |
|---|---|---|---|
| 00 | GLOBAL | Reserved | Global Variable |
| 01 | PARAM | Editor | |
| 01 | READ | I-Code | File Mode |
| 02 | TYPE | Editor | |
| 02 | WRITE | I-Code | File Mode |
| 03 | DIM | Editor | |
| 03 | UPDATE | I-Code | File Mode |
| 04 | DATA | I-Code/Editor | |
| 04 | EXEC | I-Code | File Mode |
| 05 | STOP | I-Code/Editor | |
| 05 | READ+EXEC | I-Code | File Mode |
| 06 | BYE | I-Code/Editor | |
| 06 | WRITE+EXEC | I-Code | File Mode |
| 07 | TRON | I-Code/Editor | |
| 07 | UPDATE+EXEC | I-Code | File Mode |
| 08 | TROFF | I-Code/Editor | |
| 09 | PAUSE | I-Code/Editor | |
| 0A | DEG | I-Code/Editor | |
| 0B | RAD | I-Code/Editor | |
| 0C | RETURN | I-Code/Editor | |
| 0D | LET | I-Code/Editor | |
| 0E | <cva> | I-Code/Editor | Complex Variable Assignment |
| 0F | POKE | I-Code/Editor | |
| 10 | IF | I-Code/Editor | |
| 11 | ELSE | I-Code/Editor | |
| 12 | ENDIF | I-Code/Editor | |
| 13 | FOR | I-Code/Editor | |
| 14 | NEXT | I-Code/Editor | |
| 15 | WHILE | I-Code/Editor | |
| 16 | ENDWHILE | I-Code/Editor | |
| 17 | REPEAT | I-Code/Editor | |
| 18 | UNTIL | I-Code/Editor | |
| 19 | LOOP | I-Code/Editor | |
| 1A | ENDLOOP | I-Code/Editor | |
| 1B | EXITIF | I-Code/Editor | |
| 1C | ENDEXIT | I-Code/Editor | |
| 1D | ON | I-Code/Editor | |
| 1E | ERROR | I-Code/Editor | |
| 1F | GOTO | Editor | Unbound |
| 20 | GOTO | I-Code/Editor | Bound |
| 21 | GOSUB | Editor | Unbound |
| 22 | GOSUB | I-Code/Editor | Bound |
| 23 | RUN | I-Code/Editor | |
| 24 | KILL | I-Code/Editor | |
| 25 | INPUT | I-Code/Editor | |
| 26 | I-Code/Editor | ? Becomes PRINT in the Editor | |
| 27 | CHD | I-Code/Editor | |
| 28 | CHX | I-Code/Editor | |
| 29 | CREATE | I-Code/Editor | |
| 2A | OPEN | I-Code/Editor | |
| 2B | SEEK | I-Code/Editor | |
| 2C | READ | I-Code/Editor | |
| 2D | WRITE | I-Code/Editor | |
| 2E | GET | I-Code/Editor | |
| 2F | PUT | I-Code/Editor | |
| 30 | CLOSE | I-Code/Editor | |
| 31 | RESTORE | I-Code/Editor | |
| 32 | DELETE | I-Code/Editor | |
| 33 | CHAIN | I-Code/Editor | |
| 34 | SHELL | I-Code/Editor | |
| 35 | BASE0 | I-Code/Editor | |
| 36 | BASE1 | I-Code/Editor | |
| 37 | REM | Editor | ! Becomes REM in the Editor |
| 38 | (* | Editor | |
| 39 | END | I-Code/Editor | |
| 3A | <ulrf> | Editor | Unbound Line Reference |
| 3B | <blrf> | I-Code/Editor | Bound Line Reference |
| 3C | <dex> | I-Code/Editor | Direct Execution (Unimplemented) |
| 3D | PROCEDURE | Editor | Procedure start |
| 3D | <erl> | Editor/Debug | Error Line |
| 3E | \ | I-Code/Editor | End-of-Instruction, Continue Line |
| 3F | <eol> | I-Code/Editor | End-of-Instruction and Line |
| 40 | BYTE | Editor | |
| 40 | fbyte | I-Code/Editor | VDT Entry, Field Byte Variable |
| 41 | INTEGER | Editor | |
| 41 | finteger | I-Code/Editor | VDT Entry, Field Integer Variable |
| 42 | REAL | Editor | |
| 42 | freal | I-Code/Editor | VDT Entry, Field Real Variable |
| 43 | BOOLEAN | Editor | |
| 43 | fboolean | I-Code/Editor | VDT Entry, Field Boolean Variable |
| 44 | STRING | Editor | |
| 44 | fstring | I-Code/Editor | VDT Entry, Field String Variable |
| 45 | THEN | I-Code/Editor | |
| 45 | frecord | I-Code/Editor | VDT Entry, Field Record Variable |
| 46 | TO | I-Code/Editor | |
| 47 | STEP | I-Code/Editor | |
| 48 | DO | I-Code/Editor | |
| 48 | fvectorb | I-Code/Editor | VDT Entry, Field 1 Dimensional Byte Array |
| 49 | USING | I-Code/Editor | |
| 49 | fvectori | I-Code/Editor | VDT Entry, Field 1 Dimensional Integer Array |
| 4A | : | I-Code/Editor | File Mode Operator |
| 4A | fvectorr | I-Code/Editor | VDT Entry, Field 1 Dimensional Real Array |
| 4B | , | I-Code/Editor | Comma Separator |
| 4B | fvectorl | I-Code/Editor | VDT Entry, Field 1 Dimensional Boolean Array |
| 4C | : | I-Code/Editor | Colon |
| 4C | fvectors | I-Code/Editor | VDT Entry, Field 1 Dimensional String Array |
| 4D | ( | I-Code/Editor | Left Parenthesis |
| 4D | fvectoru | I-Code/Editor | VDT Entry, Field 1 Dimensional Record Array |
| 4E | ) | I-Code/Editor | Right Parenthesis |
| 4F | [ | I-Code/Editor | Left Bracket |
| 50 | ] | I-Code/Editor | Right Bracket |
| 50 | ftableb | I-Code/Editor | VDT Entry, Field 2 Dimensional Byte Array |
| 51 | ; | I-Code/Editor | Semi-colon |
| 51 | ftablei | I-Code/Editor | VDT Entry, Field 2 Dimensional Integer Array |
| 52 | := | I-Code/Editor | AssignmentOperator |
| 52 | ftabler | I-Code/Editor | VDT Entry, Field 2 Dimensional Real Array |
| 53 | = | I-Code/Editor | AssignmentOperator |
| 53 | ftablel | I-Code/Editor | VDT Entry, Field 2 Dimensional Boolean Array |
| 54 | # | I-Code/Editor | Channel (Path) Number Operator |
| 54 | ftables | I-Code/Editor | VDT Entry, Field 2 Dimensional String Array |
| 55 | <ivgt> | I-Code/Editor | Invisible GOTO (used in many statements) |
| 55 | <ivgt> | I-Code/Editor | Invisible GOTO (special case in ON var GOTO/GOSUB statements) |
| 55 | ftableu | I-Code/Editor | VDT Entry, Field 2 Dimensional Record Array |
| 56 | Unused | ||
| 57 | Unused | ||
| 58 | fmatrixb | I-Code/Editor | VDT Entry, Field 3 Dimensional Byte Array |
| 59 | fmatrixi | I-Code/Editor | VDT Entry, Field 3 Dimensional Integer Array |
| 5A | fmatrixr | I-Code/Editor | VDT Entry, Field 3 Dimensional Real Array |
| 5B | fmatrixl | I-Code/Editor | VDT Entry, Field 3 Dimensional Boolean Array |
| 5C | fmatrixs | I-Code/Editor | VDT Entry, Field 3 Dimensional String Array |
| 5D | fmatrixu | I-Code/Editor | VDT Entry, Field 3 Dimensional Record Array |
| 5E | Unused | ||
| 5F | Unused | ||
| 60 | byte | I-Code/Editor | VDT Entry, Byte Variable |
| 61 | integer | I-Code/Editor | VDT Entry, Integer Variable |
| 62 | real | I-Code/Editor | VDT Entry, Real Variable |
| 63 | boolean | I-Code/Editor | VDT Entry, Boolean Variable |
| 64 | string | I-Code/Editor | VDT Entry,StringVariable |
| 65 | record | I-Code/Editor | VDT Entry, Record Variable |
| 66 | Unused | ||
| 67 | Unused | ||
| 68 | vectorb | I-Code/Editor | VDT Entry, 1 Dimensional Byte Array |
| 69 | vectori | I-Code/Editor | VDT Entry, 1 Dimensional Integer Array |
| 6A | vectorr | I-Code/Editor | VDT Entry, 1 Dimensional Real Array |
| 6B | vectorl | I-Code/Editor | VDT Entry, 1 Dimensional Boolean Array |
| 6C | vectors | I-Code/Editor | VDT Entry, 1 Dimensional String Array |
| 6D | vectoru | I-Code/Editor | VDT Entry, 1 Dimensional Record Array |
| 6E | Unused | ||
| 6F | Unused | ||
| 70 | tableb | I-Code/Editor | VDT Entry, 2 Dimensional Byte Array |
| 71 | tablei | I-Code/Editor | VDT Entry, 2 Dimensional Integer Array |
| 72 | tabler | I-Code/Editor | VDT Entry, 2 Dimensional Real Array |
| 73 | tablel | I-Code/Editor | VDT Entry, 2 Dimensional Boolean Array |
| 74 | tables | I-Code/Editor | VDT Entry, 2 Dimensional String Array |
| 75 | tableu | I-Code/Editor | VDT Entry, 2 Dimensional Record Array |
| 76 | Unused | ||
| 77 | Unused | ||
| 78 | matrixb | I-Code/Editor | VDT Entry, 3 Dimensional Byte Array |
| 79 | matrixi | I-Code/Editor | VDT Entry, 3 Dimensional Integer Array |
| 7A | matrixr | I-Code/Editor | VDT Entry, 3 Dimensional Real Array |
| 7B | matrixl | I-Code/Editor | VDT Entry, 3 Dimensional Boolean Array |
| 7C | matrixs | I-Code/Editor | VDT Entry, 3 Dimensional String Array |
| 7D | matrixu | I-Code/Editor | VDT Entry, 3 Dimensional Record Array |
| 7E | Unused | ||
| 7F | Unused | ||
| 80 | byte | I-Code/Editor | Instruction, Simple Byte Variable |
| 80 | pbyte | I-Code/Editor | VDT Entry, Parameter Byte Variable |
| 80 | DIR | I-Code | File Mode |
| 81 | integer | I-Code/Editor | Instruction, Simple Integer Variable |
| 81 | pinteger | I-Code/Editor | VDT Entry, Parameter Integer Variable |
| 81 | READ+DIR | I-Code | File Mode |
| 82 | real | I-Code/Editor | Instruction, Simple Real Variable |
| 82 | preal | I-Code/Editor | VDT Entry, Parameter Real Variable |
| 82 | WRITE+DIR | I-Code | File Mode |
| 83 | boolean | I-Code/Editor | Instruction, Simple Boolean Variable |
| 83 | pboolean | I-Code/Editor | VDT Entry, Parameter Boolean Variable |
| 83 | UPDATE+DIR | I-Code | File Mode |
| 84 | string | I-Code/Editor | Instruction, Simple String Variable |
| 84 | pstring | I-Code/Editor | VDT Entry, Parameter String Variable |
| 84 | EXEC+DIR | I-Code | File Mode |
| 85 | record/p | I-Code/Editor | Instruction,Record, Parameter (Simple/Record) Variable |
| 85 | vector/p | I-Code/Editor | Instruction, 1 Dimensional Array, Parameter 1 Dimensional Array Variable |
| 85 | table/p | I-Code/Editor | Instruction, 2 Dimensional Array, Parameter 2 Dimensional Array Variable |
| 85 | matrix/p | I-Code/Editor | Instruction, 3 Dimensional Array, Parameter 3 Dimensional Array Variable |
| 85 | precord | I-Code/Editor | VDT Entry, Parameter Record Variable |
| 85 | READ+EXEC+DIR | I-Code | File Mode |
| 86 | vector/p | I-Code/Editor | Instruction, 1 Dimensional Array |
| 86 | WRITE+EXEC+DIR | I-Code | File Mode |
| 87 | table/p | I-Code/Editor | Instruction, 2 Dimensional Array |
| 87 | UPDATE+EXEC+DIR | I-Code | File Mode |
| 88 | matrix/p | I-Code/Editor | Instruction, 3 Dimensional Array |
| 88 | pvectorb | I-Code/Editor | VDT Entry, Parameter 1 Dimensional Byte Array |
| 89 | varm | I-Code/Editor | Instruction, Simple/Record Variable Mirror |
| 89 | pvectori | I-Code/Editor | VDT Entry, Parameter 1 Dimensional Integer Array |
| 8A | fvectorm | I-Code/Editor | VDT Entry, Field 1 Dimensional Array Mirror |
| 8A | pvectorr | I-Code/Editor | VDT Entry, Parameter 1 Dimensional Real Array |
| 8B | ftablem | I-Code/Editor | VDT Entry, Field 2 Dimensional Array Mirror |
| 8B | pvectorl | I-Code/Editor | VDT Entry, Parameter 1 Dimensional Boolean Array |
| 8C | fmatrixm | I-Code/Editor | VDT Entry, Field 3 Dimensional Array Mirror |
| 8C | pvectors | I-Code/Editor | VDT Entry, Parameter 1 Dimensional String Array |
| 8D | <bc> | I-Code/Editor | BYTE Constant (Literal) |
| 8D | pvectoru | I-Code/Editor | VDT Entry, Parameter 1 Dimensional Record Array |
| 8E | <ic> | I-Code/Editor | INTEGER Constant (Literal) |
| 8F | <rc> | I-Code/Editor | REAL Constant (Literal) |
| 90 | " | I-Code/Editor | STRING Constant (Literal) - Beginning |
| 90 | ptableb | I-Code/Editor | VDT Entry, Parameter 2 Dimensional Byte Array |
| 91 | $ | I-Code/Editor | Hexadecimal Constant (Literal) |
| 91 | ptablei | I-Code/Editor | VDT Entry, Parameter 2 Dimensional Integer Array |
| 92 | ADDR() | I-Code/Editor | |
| 92 | ptabler | I-Code/Editor | VDT Entry, Parameter 2 Dimensional Real Array |
| 93 | <addr> | I-Code/Editor | Second Byte of ADDR() |
| 93 | ptablel | I-Code/Editor | VDT Entry, Parameter 2 Dimensional Boolean Array |
| 94 | SIZE() | I-Code/Editor | |
| 94 | ptables | I-Code/Editor | VDT Entry, Parameter 2 Dimensional String Array |
| 95 | <size> | I-Code/Editor | Second Byte of SIZE() |
| 95 | ptableu | I-Code/Editor | VDT Entry, Parameter 2 Dimensional Record Array |
| 96 | POS() | I-Code/Editor | |
| 97 | ERR() | I-Code/Editor | |
| 98 | MOD() | I-Code/Editor | Byte/Integer |
| 98 | pmatrixb | I-Code/Editor | VDT Entry, Parameter 3 Dimensional Byte Array |
| 99 | MOD() | I-Code/Editor | Real |
| 99 | pmatrixi | I-Code/Editor | VDT Entry, Parameter 3 Dimensional Integer Array |
| 9A | RND() | I-Code/Editor | |
| 9A | pmatrixr | I-Code/Editor | VDT Entry, Parameter 3 Dimensional Real Array |
| 9B | PI | I-Code/Editor | |
| 9B | pmatrixl | I-Code/Editor | VDT Entry, Parameter 3 Dimensional Boolean Array |
| 9C | SUBSTR() | I-Code/Editor | |
| 9C | pmatrixs | I-Code/Editor | VDT Entry, Parameter 3 Dimensional String Array |
| 9D | SGN() | I-Code/Editor | |
| 9D | pmatrixu | I-Code/Editor | VDT Entry, Parameter 3 Dimensional Record Array |
| 9E | SGN() | I-Code/Editor | |
| 9F | SIN() | I-Code/Editor | |
| A0 | COS() | I-Code/Editor | |
| A0 | <subr> | I-Code/Editor | Named Subroutine |
| A1 | TAN() | I-Code/Editor | |
| A2 | ASN() | I-Code/Editor | |
| A3 | ACS() | I-Code/Editor | |
| A4 | ATN() | I-Code/Editor | |
| A5 | EXP() | I-Code/Editor | |
| A6 | ABS() | I-Code/Editor | |
| A7 | ABS() | I-Code/Editor | |
| A8 | LOG() | I-Code/Editor | |
| A9 | LOG10() | I-Code/Editor | |
| AA | SQRT() | I-Code/Editor | |
| AB | SQR() | I-Code/Editor | Becomes SQRT() in the Code |
| AC | INT() | I-Code/Editor | Byte/Integer |
| AD | INT() | I-Code/Editor | Real |
| AE | FIX() | I-Code/Editor | Byte/Integer |
| AF | FIX() | I-Code/Editor | Real |
| B0 | FLOAT() | I-Code/Editor | Byte/Integer |
| B1 | FLOAT() | I-Code/Editor | Real |
| B2 | SQ() | I-Code/Editor | Byte/Integer |
| B3 | SQ() | I-Code/Editor | Real |
| B4 | PEEK() | I-Code/Editor | |
| B5 | LNOT() | I-Code/Editor | LogicalNOT |
| B6 | VAL() | I-Code/Editor | |
| B7 | LEN() | I-Code/Editor | |
| B8 | ASC() | I-Code/Editor | |
| B9 | LAND() | I-Code/Editor | Logical AND |
| BA | LOR() | I-Code/Editor | Logical OR |
| BB | LXOR() | I-Code/Editor | Logical XOR |
| BC | TRUE | I-Code/Editor | |
| BD | FALSE | I-Code/Editor | |
| BE | EOF() | I-Code/Editor | |
| BF | TRIM$() | I-Code/Editor | |
| C0 | MID$() | I-Code/Editor | |
| C1 | LEFT$() | I-Code/Editor | |
| C2 | RIGHT$() | I-Code/Editor | |
| C3 | CHR$() | I-Code/Editor | |
| C4 | STR$() | I-Code/Editor | Byte/Integer |
| C5 | STR$() | I-Code/Editor | Real |
| C6 | DATE$ | I-Code/Editor | |
| C7 | TAB | I-Code/Editor | |
| C8 | <ritc> | I-Code/Editor | Real->Byte/Integer Type Conversion |
| C8 | <fix1> | I-Code/Editor | Fix Top of Stack |
| C9 | <fix2> | I-Code/Editor | Fix Second on Stack |
| CA | <fix3> | I-Code/Editor | Fix Third on Stack |
| CB | <irtc> | I-Code/Editor | Byte/Integer->Real Type Conversion |
| CB | <flt1> | I-Code/Editor | Float Top of Stack |
| CC | <flt2> | I-Code/Editor | Float Second on Stack |
| CD | NOT() | I-Code/Editor | |
| CE | - | I-Code/Editor | (Monadic) Negate Byte/Integer |
| CF | - | I-Code/Editor | (Monadic) Negate Real |
| D0 | AND | I-Code/Editor | |
| D1 | OR | I-Code/Editor | |
| D2 | XOR | I-Code/Editor | |
| D3 | > | I-Code/Editor | Byte/Integer Comparison Operator |
| D4 | > | I-Code/Editor | Real Comparison Operator |
| D5 | > | I-Code/Editor | String Comparison Operator |
| D6 | < | I-Code/Editor | Byte/Integer Comparison Operator |
| D7 | < | I-Code/Editor | Real Comparison Operator |
| D8 | < | I-Code/Editor | String Comparison Operator |
| D9 | <> | I-Code/Editor | Byte/Integer Comparison Operator >< is converted to <> in the code |
| DA | <> | I-Code/Editor | Real Comparison Operator >< is converted to <> in the code |
| DB | <> | I-Code/Editor | String Comparison Operator >< is converted to <> in the code |
| DC | <> | I-Code/Editor | Boolean Comparison Operator >< is converted to <> in the code |
| DD | = | I-Code/Editor | Byte/Integer Comparison Operator |
| DE | = | I-Code/Editor | Real Comparison Operator |
| DF | = | I-Code/Editor | String Comparison Operator |
| E0 | = | I-Code/Editor | Boolean Comparison Operator |
| E1 | >= | I-Code/Editor | Byte/Integer Greater/Equal Operator |
| E2 | >= | I-Code/Editor | Real Greater/Equal Operator |
| E3 | >= | I-Code/Editor | String Greater/Equal Operator |
| E4 | <= | I-Code/Editor | Byte/Integer Less/Equal Operator |
| E5 | <= | I-Code/Editor | Real Less/Equal Operator |
| E6 | <= | I-Code/Editor | String Less/Equal Operator |
| E7 | + | I-Code/Editor | Byte/Integer Add Operator |
| E8 | + | I-Code/Editor | Real Add Operator |
| E9 | + | I-Code/Editor | String Concantenate Operator |
| EA | - | I-Code/Editor | Byte/Integer Subtract Operator (Dyadic) |
| EB | - | I-Code/Editor | Real Subtract Operator (Dyadic) |
| EC | * | I-Code/Editor | Byte/Integer Multiply Operator |
| ED | * | I-Code/Editor | Real Multiply Operator |
| EE | / | I-Code/Editor | Byte/Integer Divide Operator |
| EF | / | I-Code/Editor | Real Divide Operator |
| F0 | ^ | I-Code/Editor | Exponent Operator |
| F1 | ** | I-Code/Editor | Exponent Operator |
| F2 | varm/p | I-Code/Editor | Instruction, Simple/Record, Parameter Variable Mirror |
| F3 | vectorm/p | I-Code/Editor | Instruction, 1 Dimensional Array, Parameter 1 Dimensional Array Mirror |
| F4 | tablem/p | I-Code/Editor | Instruction, 2 Dimensional Array, Parameter 2 Dimensional Array Mirror |
| F5 | matrixm/p | I-Code/Editor | Instruction, 3 Dimensional Array, Parameter 3 Dimensional Array Mirror |
| F6 | field | I-Code/Editor | Instruction, Field Variable |
| F7 | UPDATE | Editor | File Mode |
| F7 | fvector | I-Code/Editor | Instruction, Field 1 Dimensional Array |
| F8 | EXEC | Editor | File Mode |
| F8 | ftable | I-Code/Editor | Instruction, Field 2 Dimensional Array |
| F9 | DIR | Editor | File Mode |
| F9 | fmatrix | I-Code/Editor | Instruction, Field 3 Dimensional Array |
| FA | Unused | ||
| FB | Unused | ||
| FC | Unused | ||
| FD | Unused | ||
| FE | Unused | ||
| FF | " | I-Code/Editor | STRING Constant (Literal) - Terminator |