13 *NOTE: Every effort has been made to ensure the accuracy and robustness of this
14 manual and the associated software. However, because Reboot is constantly improving
15 and updating its computer software, it is unable to guarantee
16 the accuracy of printed or duplicated material after the date of publication and
17 disclaims liability for changes, errors or omissions.*
20 *Copyright © 2011-2022, the rmac authors*
22 *All rights reserved.*
34 This document describes RMAC, a fast macro assembler for the 68000. RMAC currently
35 runs on the any POSIX compatible platform and the Atari ST. It was initially written
36 at Atari Corporation by programmers who needed a high performance assembler
37 for their work. Then, more than 20 years later, because there was still a need for
38 such an assembler and what was available wasn't up to expectations, Subqmod
39 and eventually Reboot continued work on the freely released source, adding Jaguar
40 extensions and fixing bugs. Over time the assembler has been extended by adding
41 support for Motorola's 68020/30/40/60, 68881/2, DSP56001 CPUs as well as Atari's
42 Object Processor (OP) found on the Atari Jaguar.
44 RMAC is intended to be used by programmers who write mostly in assembly language.
45 It was not originally a back-end to a C compiler, therefore it
46 has creature comfort that are usually neglected in such back-end assemblers. It
47 supports include files, macros, symbols with limited scope, some limited control
48 structures, and other features. RMAC is also blindingly fast, another feature
49 often sadly and obviously missing in today's assemblers.\ [1]_
51 RMAC is not entirely compatible with the AS68 assembler provided with
52 the original Atari ST Developer's Kit, but most changes are minor and a few minutes
53 with an editor should allow you to assemble your current source files. If you are an
54 AS68 user, before you leap into the unknown please read the section on Notes for
57 .. [1] It processes 30,000 lines a minute on a lightly loaded VAX 11/780; maybe 40,000 on a 520-ST with an SH-204 hard disk. Yet it could be sped up even more with some effort and without resorting to assembly language; C doesn't have to be slow!
63 * The distribution disk contains a file called README that you should read.
64 This file contains important nays about the contents of the distribution disk
65 and summarizes the most recent changes to the tools.
67 * Hard disk users can simply copy the executable files to their work or binary
68 directories. People with floppy disks can copy the executables to ramdisks,
69 install the assembler with the -q option, or even work right off of the floppies.
71 * You will need an editor that can produce "normal" format text files. Micro
72 Emacs will work well, as will most other commercial program editors, but not
73 most word processors (such as First Word or Microsoft Write).
75 * You will probably want to examine or get a listing of the file "ATARI.S". It
76 contains lots of definitions for the Atari ST, including BIOS variables, most
77 BIOS, XBIOS and GEMDOS traps, and line-A equates. We (or you) could
78 split the file up into pieces (a file for line-A equates, a file for hardware and
79 BIOS variables and so on), but RMAC is so fast that it doesn't matter
82 * Read the rest of the manual, especially the first two chapters on The Command Line and Using RMAC.
83 Also, `Notes for migrating from other 68000 assemblers`_ will save a lot of time and frustration in the long run.
84 The distribution disk contains example
85 programs that you can look at, assemble and modify.
90 The assembler is called "**rmac**" or "**rmac.prg**". The command line takes the form:
92 **rmac** [*switches*] [*files* ...]
94 A command line consists of any number of switches followed by the names of files
95 to assemble. A switch is specified with a dash (**-**) followed immediately by a key
96 character. Key characters are not case-sensitive, so "**-d**" is the same as "**-D**". Some
97 switches accept (or require) arguments to immediately follow the key character,
98 with no spaces in between.
100 Switch order is important. Command lines are processed from left to right in
101 one pass, and switches usually take effect when they are encountered. In general it
102 is best to specify all switches before the names of any input files.
104 If the command line is entirely empty then RMAC prints a copyright message
105 along with usage info and exit.
107 Input files are assumed to have the extension "**.s**"; if a filename has no extension
108 (i.e. no dot) then "**.s**" will be appended to it. More than one source filename may be
109 specified: the files are assembled into one object file, as if they were concatenated.
111 RMAC normally produces object code in "**file.o**" if "**file.s**" is the first
112 input filename. If the first input file is a special character device, the output name
113 is noname.o. The **-o** switch (see below) can be used change the output file name.
116 =================== ===========
118 =================== ===========
119 -dname\ *[=value]* Define symbol, with optional value.
120 -e\ *[file[.err]]* Direct error messages to the specified file.
121 -fa ALCYON output object file format (implied when **-ps** is enabled).
122 -fb BSD COFF output object file format.
123 -fe ELF output object file format.
124 -fr Absolute address. Source code is required to have one .org statement.
125 -fx Atari 800 com/exe/xex output object file format.
126 -g Generate source level debug info. Requires BSD COFF object file format.
127 -i\ *path* Set include-file directory search path.
128 -l\ *[file[prn]]* Construct and direct assembly listing to the specified file.
129 -l\ *\*[filename]* Create an output listing file without pagination.
130 -m\ *cpu* Switch CPU type
150 `tom - Jaguar GPU JRISC`
152 `jerry - Jaguar DSP JRISC`
154 -o\ *file[.o]* Direct object code output to the specified file.
155 +/~oall Turn all optimisations on/off
156 +o\ *0-30*/*p* Enable specific optimisation
157 ~o\ *0-30*/*p* Disable specific optimisation
159 `0: Absolute long adddresses to word`
161 `1: move.l #x,Dn/An to moveq`
163 `2: Word branches to short`
165 `3: Outer displacement 0(An) to (An)`
169 `5: 68020+ Absolute long base/outer displacement to word`
171 `6: Convert null short branches to NOP`
173 `7: Convert clr.l Dn to moveq #0,Dn`
175 `8: Convert adda.w/l #x,Dy to addq.w/l #x,Dy`
177 `9: Convert adda.w/l #x,Dy to lea x(Dy),Dy`
179 `10: 56001 Use short format for immediate values if possible`
181 `11: 56001 Auto convert short addressing mode to long (default: on)`
183 `30: Enforce PC relative (alternative name: op)`
185 -p Produce an executable (**.prg**) output file.
186 -ps Produce an executable (**.prg**) output file with symbols.
187 -px Produce an executable (**.prg**) output file with extended symbols.
188 -q Make RMAC resident in memory (Atari ST only).
189 -r *size* automatically pad the size of each
190 segment in the output file until the size is an integral multiple of the
191 specified boundary. Size is a letter that specifies the desired boundary.
193 `-rw Word (2 bytes, default alignment)`
197 `-rp Phrase (8 bytes)`
199 `-rd Double Phrase (16 bytes)`
201 `-rq Quad Phrase (32 bytes)`
202 -s Warn about unoptimized long branches and applied optimisations.
203 -u Force referenced and undefined symbols global.
204 -v Verbose mode (print running dialogue).
205 -x Turn on debugging mode.
206 -yn Set listing page size to n lines.
207 -4 Use C style operator precedence.
208 file\ *[s]* Assemble the specified file.
209 =================== ===========
211 The switches are described below. A summary of all the switches is given in
215 The **-d** switch permits symbols to be defined on the command line. The name
216 of the symbol to be defined immediately follows the switch (no spaces). The
217 symbol name may optionally be followed by an equals sign (=) and a decimal
218 number. If no value is specified the symbol's value is zero. The symbol at-
219 tributes are "defined, not referenced, and absolute". This switch is most useful
220 for enabling conditionally-assembled debugging code on the command line; for
225 -dDEBUG -dLoopCount=999 -dDebugLevel=55
228 The -e switch causes RMAC to send error messages to a file, instead of the
229 console. If a filename immediately follows the switch character, error messages
230 are written to the specified file. If no filename is specified, a file is created with
231 the default extension "**.err**" and with the root name taken from the first input
232 file name (e.g. error messages are written to "**file.err**" if "**file**" or "**file.s**" is
233 the first input file name). If no errors are encountered, then no error listing
234 file is created. Beware! If an assembly produces no errors, any error file from
235 a previous assembly is not removed.
238 The **-g** switch causes RMAC to generate source-level debug symbols using the
239 stabs format. When linked with a compatible linker such as RLN, these symbols
240 can be used by source-level debuggers such as rdbjag, wdb, or gdb to step
241 through assembly code line-by-line with all the additional context of labels,
242 macros, constants, register equates, etc. available in the original assembly
243 listings rather than relying on the simple disassembly or raw machine code
244 available when stepping through instruction-by-instruction. This option only
245 works with the BSD COFF object file format, as the others do not use the
246 a.out-style symbol tables required by stabs, and RMAC does not currently
247 support placing stabs debug symbols in their own dedicated section in ELF
251 The **-i** switch allows automatic directory searching for include files. A list of
252 semi-colon seperated directory search paths may be mentioned immediately
253 following the switch (with no spaces anywhere). For example:
257 -im:;c:include;c:include\sys
259 will cause the assembler to search the current directory of device **M**, and the
260 directories include and include\sys on drive **C**. If *-i* is not specified, and the
261 enviroment variable "**RMACPATH**" exists, its value is used in the same manner.
262 For example, users of the Mark Williams shell could put the following line in
263 their profile script to achieve the same result as the **-i** example above:
267 setenv RMACPATH="m:;c:include;c:include\sys"
269 The -l switch causes RMAC to generate an assembly listing file. If a file-
270 name immediately follows the switch character, the listing is written to the
271 specified file. If no filename is specified, then a listing file is created with the
272 default extension "**.prn**" and with the root name taken from the first input file
273 name (e.g. the listing is written to "**file.prn**" if "**file**" or "**file.s**" is the first
276 The -o switch causes RMAC to write object code on the specified file. No
277 default extension is applied to the filename. For historical reasons the filename
278 can also be seperated from the switch with a space (e.g. "**-o file**").
283 The **-p** and **-ps** switches cause RMAC to produce an Atari ST executable
284 file with the default extension of "**.prg**". If there are any external references
285 at the end of the assembly, an error message is emitted and no executable file
286 is generated. The **-p** switch does not write symbols to the executable file. The
287 **-ps** switch includes symbols (Alcyon format) in the executable file.
289 The **-q** switch is aimed primarily at users of floppy-disk-only systems. It causes
290 RMAC to install itself in memory, like a RAMdisk. Then the program
291 **m.prg** (which is very short - less than a sector) can be used instead of
292 **mac.prg**, which can take ten or twelve seconds to load. (**NOTE** not available
293 for now, might be re-implemented in the future).
295 The **-s** switch causes RMAC to generate a list of unoptimized forward
296 branches as warning messages. This is used to point out branches that could
297 have been short (e.g. "bra" could be "bra.s").
299 The **-u** switch takes effect at the end of the assembly. It forces all referenced
300 and undefined symbols to be global, exactly as if they had been made global
301 with a **.extern** or **.globl** directive. This can be used if you have a lot of
302 external symbols, and you don't feel like declaring them all external.
304 The **-v** switch turns on a "verbose" mode in which RMAC prints out (for
305 example) the names of the files it is currently processing. Verbose mode is
306 automatically entered when RMAC prompts for input with a star.
308 The **-y** switch, followed immediately by a decimal number (with no intervening
309 space), sets the number of lines in a page. RMAC will produce *N* lines
310 before emitting a form-feed. If *N* is missing or less than 10 an error message is
313 Use C style order of precedence in expressions. See `Order of Evaluation`_ for more
319 Let's assemble and link some example programs. These programs are included
320 on the distribution disk in the "**EXAMPLES**" directory - you should copy them to
321 your work area before continuing. In the following examples we adopt the conven-
322 tions that the shell prompt is a percent sign (%) and that your input (the stuff you
323 type) is presented in **bold face**.
325 If you have been reading carefully, you know that RMAC can generate
326 an executable file without linking. This is useful for making small, stand alone
327 programs that don't require externals or library routines. For example, the following
335 could be replaced by the single command:
341 since you don't need the linker for stand-alone object files.
343 Successive source files named in the command line are are concatenated, as in
344 this example, which assembles three files into a single executable, as if they were
349 % rmac -p bugs shift images
351 Of course you can get the same effect by using the **.include** directive, but sometimes
352 it is convenient to do the concatenation from the command line.
354 Here we have an unbelievably complex command line:
358 % rmac -lzorf -y95 -o tmp -ehack -Ddebug=123 -ps example
360 This produces a listing on the file called "**zorf.prn**" with 95 lines per page, writes
361 the executable code (with symbols) to a file called "**tmp.prg**", writes an error listing
362 to the file "**hack.err**", specifies an include-file path that includes the current
363 directory on the drive "**M:**," defines the symbol "**debug**" to have the value 123, and
364 assembles the file "**example.s**". (Take a deep breath - you got all that?)
366 One last thing. If there are any assembly errors, RMAC will terminate
367 with an exit code of 1. If the assembly succeeds (no errors, although there may be
368 warnings) the exit code will be 0. This is primarily for use with "make" utilities.
370 Things You Should Be Aware Of
371 '''''''''''''''''''''''''''''
372 RMAC is a one pass assembler. This means that it gets all of its work done by
373 reading each source file exactly once and then "back-patching" to fix up forward
374 references. This one-pass nature is usually transparent to the programmer, with
375 the following important exceptions:
377 * In listings, the object code for forward references is not shown. Instead, lower-
378 case "xx"s are displayed for each undefined byte, as in the following example:
382 60xx 1: bra.s.2 ;forward branch
383 xxxxxxxx dc.l .2 ;forward reference
384 60FE .2: bra.s.2 ;backward reference
386 * Forward branches (including **BSR**\s) are never optimized to their short forms.
387 To get a short forward branch it is necessary to explicitly use the ".s" suffix in
389 * Error messages may appear at the end of the assembly, referring to earlier source
390 lines that contained undefined symbols.
391 * All object code generated must fit in memory. Running out of memory is a
392 fatal error that you must deal with by splitting up your source files, re-sizing
393 or eliminating memory-using programs such as ramdisks and desk accessories,
398 RMAC does not optimize forward branches for you, but it will tell you about
399 them if you use the -s (short branch) option:
404 "example.s", line 20: warning: unoptimized short branch
406 With the -e option you can redirect the error output to a file, and determine by
407 hand (or editor macros) which forward branches are safe to explicitly declare short.
409 `Notes for migrating from other 68000 assemblers`_
410 ''''''''''''''''''''''''''''''''''''''''''''''''''
411 RMAC is not entirely compatible with the other popular assemblers
412 like Devpac or vasm. This section
413 outlines the major differences. In practice, we have found that very few changes are
414 necessary to make other assemblers' source code assemble.
416 * A semicolon (;) must be used to introduce a comment,
417 except that a star (*)
418 may be used in the first column. AS68 treated anything following the operand
419 field, preceeded by whitespace, as a comment. (RMAC treats a star that
420 is not in column 1 as a multiplication operator).
421 * Labels require colons (even labels that begin in column 1).
423 * Conditional assembly directives are called **if**, **else** and **endif**.
424 Devpac and vasm call these
425 **ifne**, **ifeq** (etc.), and **endc**.
426 * The tilde (~) character is an operator, and back-quote (`) is an illegal character.
427 AS68 permitted the tilde and back-quote characters in symbols.
428 * There are no equivalents to org or section directives apart from .text, .data, .bss.
429 The **.xdef** and **.xref** directives are not implemented,
430 but **.globl** makes these unnecessary anyway.
432 * The location counter cannot be manipulated with a statement of the form:
438 Exceptions to this rule are when outputting a binary using the **-fr** switch,
439 6502 mode, and Jaguar GPU/DSP.
440 * Back-slashes in strings are "electric" characters that are used to escape C-like
441 character codes. Watch out for GEMDOS path names in ASCII constants -
442 you will have to convert them to double-backslashes.
443 * Expression evaluation is done left-to-right without operator precedence. Use parentheses to
444 force the expression evaluation as you wish. Alternatively, use the **-4** switch to switch
445 to C style precedence. For more information refer to `Order of Evaluation`_.
446 * Mark your segments across files.
447 Branching to a code segment that could be identified as BSS will cause a "Error: cannot initialize non-storage (BSS) section"
448 * In 68020+ mode **Zan** and **Zri** (register suppression) is not supported.
449 * rs.b/rs.w/rs.l/rscount/rsreset can be simulated in rmac using **.abs**.
450 For example the following source:
460 size_so_far equ rscount
472 size_so_far equ ^^abscount
473 * A rare case: if your macro contains something like:
483 then by the assembler's design this will fail as the parameters are automatically converted to hex. Changing the code like this works:
495 For those using editors other than the "Emacs" style ones (Micro-Emacs, Mince,
496 etc.) this section documents the source file format that RMAC expects.
498 * Files must contain characters with ASCII values less than 128; it is not per-
499 missable to have characters with their high bits set unless those characters are
500 contained in strings (i.e. between single or double quotes) or in comments.
502 * Lines of text are terminated with carriage-return/line-feed, linefeed alone, or
503 carriage-return alone.
505 * The file is assumed to end with the last terminated line. If there is text beyond
506 the last line terminator (e.g. control-Z) it is ignored.
513 A statement may contain up to four fields which are identified by order of ap-
514 pearance and terminating characters. The general form of an assembler statement
519 label: operator operand(s) ; comment
521 The label and comment fields are optional. An operand field may not appear
522 without an operator field. Operands are seperated with commas. Blank lines are
523 legal. If the first character on a line is an asterisk (*) or semicolon (;) then the
524 entire line is a comment. A semicolon anywhere on the line (except in a string)
525 begins a comment field which extends to the end of the line.
527 The label, if it appears, must be terminated with a single or double colon. If
528 it is terminated with a double colon it is automatically declared global. It is illegal
529 to declare a confined symbol global (see: `Symbols and Scope`_).
531 As an addition, the exclamation mark character (**!**) can be placed at the very first
532 character of a line to disbale all optimisations for that specific line, i.e.
536 !label: operator operand(s) ; comment
540 A statement may also take one of these special forms:
542 *symbol* **equ** *expression*
544 *symbol* **=** *expression*
546 *symbol* **==** *expression*
548 *symbol* **set** *expression*
550 *symbol* **reg** *register list*
552 The first two forms are identical; they equate the symbol to the value of an
553 expression, which must be defined (no forward references). The third form, double-
554 equals (==), is just like an equate except that it also makes the symbol global. (As
555 with labels, it is illegal to make a confined equate global.) The fourth form allows
556 a symbol to be set to a value any number of times, like a variable. The last form
557 equates the symbol to a 16-bit register mask specified by a register list. It is possible
558 to equate confined symbols (see: `Symbols and Scope`_). For example:
562 cr equ 13 carriage-return
564 DEBUG == 1 global debug flag
566 count set count + 1 increment variable
567 .rags reg d3-d7/a3-a6 register list
568 .cr 13 confined equate
572 Symbols may start with an uppercase or lowercase letter (A-Z a-z), an underscore
573 (**_**), a question mark (**?**) or a period (**.**). Each remaining character may be an
574 upper or lowercase letter, a digit (**0-9**), an underscore, a dollar sign (**$**), or a question
575 mark. (Periods can only begin a symbol, they cannot appear as a symbol
576 continuation character). Symbols are terminated with a character that is not a
577 symbol continuation character (e.g. a period or comma, whitespace, etc.). Case is
578 significant for user-defined symbols, but not for 68000 mnemonics, assembler direc-
579 tives and register names. Symbols are limited to 100 characters. When symbols
580 are written to the object file they are silently truncated to eight (or sixteen) char-
581 acters (depending on the object file format) with no check for (or warnings about)
584 For example, all of the following symbols are legal and unique:
588 reallyLongSymbolName .reallyLongConfinedSymbolName
589 a10 ret move dc frog aa6 a9 ????
590 .a1 .ret .move .dc .frog .a9 .9 ????
591 .0 .00 .000 .1 .11. .111 . ._
592 _frog ?zippo? sys$syetem atari Atari ATARI aTaRi
594 while all of the following symbols are illegal:
598 12days dc.10 dc.z 'quote .right.here
599 @work hi.there $money$ ~tilde
602 Symbols beginning with a period (**.**) are *confined*; their scope is between two
603 normal (unconfined) labels. Confined symbols may be labels or equates. It is illegal
604 to make a confined symbol global (with the ".globl" directive, a double colon, or a
605 double equals). Only unconfined labels delimit a confined symbol's scope; equates
606 (of any kind) do not count. For example, all symbols are unique and have unique
607 values in the following:
618 .loop: move.w -1,(a0)+
622 Confined symbols are useful since the programmer has to be much less inventive
623 about finding small, unique names that also have meaning.
625 It is legal to define symbols that have the same names as processor mnemonics
626 (such as "**move**" or "**rts**") or assembler directives (such as "**.even**"). Indeed, one
627 should be careful to avoid typographical errors, such as this classic (in 6502 mode):
635 which equates a confined symbol to a hexadecimal value, rather than setting the
636 location counter, which the .org directive does (without the equals sign).
640 The following names, in all combinations of uppercase and lowercase, are keywords
641 and may not be used as symbols (e.g. labels, equates, or the names of macros):
649 d0 d1 d2 d3 d4 d5 d6 d7
650 a0 a1 a2 a3 a4 a5 a6 a7
652 r0 r1 r2 r3 r4 r5 r6 r7
653 r8 r9 r10 r11 r12 r13 r14 r15
657 x x0 x1 x2 y y0 y1 y2
658 a a0 a1 a2 b b0 b1 b2 ab ba
659 mr omr la lc ssh ssl ss
660 n0 n1 n2 n3 n4 n5 n6 n7
661 m0 m1 m2 m3 m4 m5 m6 m7
662 r0 r1 r2 r3 r4 r5 r6 r7
667 Numbers may be decimal, hexadecimal, octal, binary or concatenated ASCII. The
668 default radix is decimal, and it may not be changed. Decimal numbers are specified
669 with a string of digits (**0-9**). Hexadecimal numbers are specified with a leading
670 dollar sign (**$**) followed by a string of digits and uppercase or lowercase letters (**A-F
671 a-f**). Octal numbers are specified with a leading at-sign (**@**) followed by a string
672 of octal digits (**0-7**). Binary numbers are specified with a leading percent sign
673 (**%**) followed by a string of binary digits (**0-1**). Concatenated ASCII constants are
674 specified by enclosing from one to four characters in single or double quotes. For
686 Negative numbers Are specified with a unary minus (**-**). For example:
695 Strings are contained between double (") or single ( ') quote marks. Strings may
696 contain non-printable characters by specifying "backslash" escapes, similar to the
697 ones used in the C programming language. RMAC will generate a warning if a
698 backslash is followed by a character not appearing below:
703 \n $0a line-feed (newline)
706 \r $0c1 carriage-return
712 It is possible for strings (but not symbols) to contain characters with their high
713 bits set (i.e. character codes 128...255).
715 You should be aware that backslash characters are popular in GEMDOS path
716 names, and that you may have to escape backslash characters in your existing source
717 code. For example, to get the file "'c:\\auto\\ahdi.s'" you would specify the string
718 "`c:\\\\auto\\\\ahdi.s`".
722 Register lists are special forms used with the **movem** mnemonic and the **.reg**
723 directive. They are 16-bit values, with bits 0 through 15 corresponding to registers
724 **D0** through **A7**. A register list consists of a series of register names or register
725 ranges seperated by slashes. A register range consists of two register names, Rm
726 and Rn,m<n, seperated by a dash. For example:
734 d0/d1/a0-a3/d7/a6-a7 $CF83
738 Register lists and register equates may be used in conjunction with the movem
739 mnemonic, as in this example:
743 temps reg d0-d2/a0-a2 ; temp registers
744 keeps reg d3-d7/d3-a6 ; registers to preserve
745 allregs reg d0-d7/a0-a7 ; all registers
746 movem.l #temps,-(sp) ; these two lines ...
747 movem.l d0-d2/a0-a2,-(sp) ; are identical
748 movem.l #keeps,-(sp) ; save "keep" registers
749 movem.l (sp)+,#keeps ; restore "keep" registers
754 `Order of Evaluation`_
755 ''''''''''''''''''''''
756 All values are computed with 32-bit 2's complement arithmetic. For boolean operations
757 (such as if or **assert**) zero is considered false, and non-zero is considered
760 **Expressions are evaluated strictly left-to-right, with no
761 regard for operator precedence.**
763 Thus the expression "1+2*3" evaluates to 9, not 7. However, precedence may be
764 forced with parenthesis (**()**) or square-brackets (**[]**).
766 All the above behavior is the default. However if the command line switch **-4**
767 is used, then C style of operator precedence is enforced. The following list
768 shows the order of precedence in this mode, from lowest to highest:
776 * relational = < <= >= > !=
786 Expressions belong to one of three classes: undefined, absolute or relocatable. An
787 expression is undefined if it involves an undefined symbol (e.g. an undeclared sym-
788 bol, or a forward reference). An expression is absolute if its value will not change
789 when the program is relocated (for instance, the number 0, all labels declared in
790 an abs section, and all Atari ST hardware register locations are absolute values).
791 An expression is relocatable if it involves exactly one symbol that is contained in a
792 text, data or BSS section.
794 Only absolute values may be used with operators other than addition (+) or
795 subtraction (-). It is illegal, for instance, to multiply or divide by a relocatable or
796 undefined value. Subtracting a relocatable value from another relocatable value in
797 the same section results in an absolute value (the distance between them, positive
798 or negative). Adding (or subtracting) an absolute value to or from a relocatable
799 value yeilds a relocatable value (an offset from the relocatable address).
801 It is important to realize that relocatable values belong to the sections they
802 are defined in (e.g. text, data or BSS), and it is not permissible to mix and match
803 sections. For example, in this code:
807 linel: dc.l line2, line1+8
808 line2: dc.l line1, line2-8
809 line3: dc.l line2-line1, 8
810 error: dc.l line1+line2, line2 >> 1, line3/4
812 Line 1 deposits two longwords that point to line 2. Line 2 deposits two longwords
813 that point to line 1. Line 3 deposits two longwords that have the absolute value
814 eight. The fourth line will result in an assembly error, since the expressions (re-
815 spectively) attempt to add two relocatable values, shift a relocatable value right by
816 one, and divide a relocatable value by four.
818 The pseudo-symbol "*****" (star) has the value that the current section's location
819 counter had at the beginning of the current source line. For example, these two
820 statements deposit three pointers to the label "**bar**":
827 Similarly, the pseudo-symbol "**$**" has the value that the current section's location
828 counter has, and it is kept up to date as the assembler deposits information
829 "across" a line of source code. For example, these two statements deposit four
830 pointers to the label "zip":
840 ================================ ==========================================
842 ================================ ==========================================
843 **-** Unary minus (2's complement).
844 **!** Logical (boolean) NOT.
845 **~** Tilde: bitwise not (l's complement).
846 **^^defined** *symbol* True if symbol has a value.
847 **^^referenced** *symbol* True if symbol has been referenced.
848 **^^streq** *string1*, *string2* True if the strings are equal.
849 **^^macdef** *macroName* True if the macro is defined.
850 **^^abscount** Returns the size of current .abs section
851 **^^filesize** *string_filename* Returns the file size of supplied filename
852 ================================ ==========================================
854 * The boolean operators generate the value 1 if the expression is true, and 0 if it is not.
856 * A symbol is referenced if it is involved in an expression.
858 any combination of attributes: undefined and unreferenced, defined and unref-
859 erenced (i.e. declared but never used), undefined and referenced (in the case
860 of a forward or external reference), or defined and referenced.
867 =========== ==============================================
869 =========== ==============================================
870 \ + - * / The usual arithmetic operators.
871 % Modulo. Do *not* attempt to modulo by 0 or 1.
872 & | ^ Bit-wise **AND**, **OR** and **Exclusive-OR**.
873 << >> Bit-wise shift left and shift right.
874 < <= >= > Boolean magnitude comparisons.
876 <> != Boolean inequality.
877 =========== ==============================================
879 * All binary operators have the same precedence:
880 expressions are evaluated strictly left to right,
881 with the exception of the **-4** switch. For more information
882 refer to `Order of Evaluation`_.
884 * Division or modulo by zero yields an assembly error.
886 * The "<>" and "!=" operators are synonyms.
888 * Note that the modulo operator (%) is also used to introduce binary constants
889 (see: `Constants`_). A percent sign should be followed by at least one space if
890 it is meant to be a modulo operator, and is followed by a '0' or '1'.
895 ============ =========================================
896 Special Form Description
897 ============ =========================================
898 **^^date** The current system date (Gemdos format).
899 **^^time** The current system time (Gemdos format).
900 ============ =========================================
902 * The "**^^date**" special form expands to the current system date, in Gemdos
903 format. The format is a 16-bit word with bits 0 ...4 indicating the day of the
904 month (1...31), bits 5...8 indicating the month (1...12), and bits 9...15
905 indicating the year since 1980, in the range 0...119.
907 * The "**^^time**" special form expands to the current system time, in Gemdos
908 format. The format is a 16-bit word with bits 0...4 indicating the current
909 second divided by 2, bits 5...10 indicating the current minute 0...59. and
910 bits 11...15 indicating the current hour 0...23.
912 `Example Expressions`_
913 ''''''''''''''''''''''
917 line address contents source code
918 ---- ------- -------- -------------------------------
919 1 00000000 4480 lab1: neg.l d0
920 2 00000002 427900000000 lab2: clr.w lab1
921 3 =00000064 equ1 = 100
922 4 =00000096 equ2 = equ1 + 50
923 5 00000008 00000064 dc.l lab1 + equ1
924 6 0000000C 7FFFFFE6 dc.l (equl + ~equ2) >> 1
925 7 00000010 0001 dc.w ^^defined equl
926 8 00000012 0000 dc.w ^^referenced lab2
927 9 00000014 00000002 dc.l lab2
928 10 00000018 0001 dc.w ^^referenced lab2
929 11 0000001A 0001 dc.w lab1 = (lab2 - 6)
931 Lines 1 through four here are used to set up the rest of the example. Line 5 deposits
932 a relocatable pointer to the location 100 bytes beyond the label "**lab1**". Line 6 is
933 a nonsensical expression that uses the and right-shift operators. Line 7 deposits
934 a word of 1 because the symbol "**equ1**" is defined (in line 3).
936 Line 8 deposits a word of 0 because the symbol "**lab2**", defined in line 2, has
937 not been referenced. But the expression in line 9 references the symbol "**lab2**", so
938 line 10 (which is a copy of line-8) deposits a word of 1. Finally, line 11 deposits a
939 word of 1 because the Boolean equality operator evaluates to true.
941 The operators "**^^defined**" and "**^^referenced**" are particularly useful in
942 conditional assembly. For instance, it is possible to automatically include debugging
943 code if the debugging code is referenced, as in:
947 lea string,a0 ; AO -> message
948 jsr debug ; print a message
950 string: dc.b "Help me, Spock!",0 ; (the message)
954 .iif ^^referenced debug, .include "debug.s"
956 The **jsr** statement references the symbol debug. Near the end of the source file, the
957 "**.iif**" statement includes the file "**debug.s**" if the symbol debug was referenced.
959 In production code, presumably all references to the debug symbol will be removed,
960 and the debug source file will not be included. (We could have as easily made the
961 symbol **debug** external, instead of including another source file).
967 Assembler directives may be any mix of upper- or lowercase. The leading periods
968 are optional, though they are shown here and their use is encouraged. Directives
969 may be preceeded by a label; the label is defined before the directive is executed.
970 Some directives accept size suffixes (**.b**, **.s**, **.w**, **.1**, **.d**, **.x**, **.p**, or **.q**);
971 the default is word (**.w**) if no size is specified. The **.s** suffix is identical to **.b**,
972 with the exception of being used in a **dc** statement. In that case the **.s**
973 refers to single precision floating point numbers.
974 Directives relating to the 6502 are described in the chapter on `6502 Support`_.
980 If the location counter for the current section is odd, make it even by adding
981 one to it. In text and data sections a zero byte is deposited if necessary.
985 Align the program counter to the next integral long boundary (4 bytes).
986 Note that GPU/DSP code sections are not contained in their own
987 segments and are actually part of the TEXT or DATA segments.
988 Therefore, to align GPU/DSP code, align the current section before and
989 after the GPU/DSP code.
992 This directive is similar to the standard ‘C’ library printf() function
993 and is used to print user messages from the assembly process. You can
994 print any string or valid expression. Several format flags that can be used
995 to format your output are also supported.
1011 .print “Mask: $”,/x/w MASK
1012 .print “Value: “,/d/l VALUE
1016 Align the program counter to the next integral phrase boundary (8 bytes).
1017 Note that GPU/DSP code sections are not contained in their own
1018 segments and are actually part of the TEXT or DATA segments.
1019 Therefore, to align GPU/DSP code, align the current section before and
1020 after the GPU/DSP code.
1024 Align the program counter to the next integral double phrase boundary (16
1025 bytes). Note that GPU/DSP code sections are not contained in their own
1026 segments and are actually part of the TEXT or DATA segments.
1027 Therefore, to align GPU/DSP code, align the current section before and
1028 after the GPU/DSP code.
1032 Align the program counter to the next integral quad phrase boundary (32
1033 bytes). Note that GPU/DSP code sections are not contained in their own
1034 segments and are actually part of the TEXT or DATA segments.
1035 Therefore, to align GPU/DSP code, align the current section before and
1036 after the GPU/DSP code.
1038 **.align** *expression*
1040 A generalised version of the above directives, this will align the program
1041 counter to the boundary of the specified value. Note that there is not much
1042 error checking happening (only values 0 and 1 are rejected). Also note that
1043 in DSP56001 mode the align value is assumed to be in DSP words, i.e. 24 bits.
1045 **.assert** *expression* [,\ *expression*...]
1047 Assert that the conditions are true (non-zero). If any of the comma-seperated
1048 expressions evaluates to zero an assembler warning is issued. For example:
1052 .assert *-start = $76
1053 .assert stacksize >= $400
1061 Switch to the BSS, data or text segments. Instructions and data may not
1062 be assembled into the BSS-segment, but symbols may be defined and storage
1063 may be reserved with the **.ds** directive. Each assembly starts out in the text
1072 Enable different flavours of the MC68000 family of CPUs. Bear in mind that not all
1073 instructions and addressing modes are available in all CPUs so the correct CPU
1074 should be selected at all times. Notice that it is possible to switch CPUs
1080 Enable FPU support. Note that *.68882* is on by default when selecting *.68030*.
1084 Switch to Motorola DSP56001 mode.
1086 **.org** *location* [*X:*/*Y:*/*P:*/*L:*]
1088 This directive sets the value of the location counter (or **pc**) to location, an
1089 expression that must be defined and absolute. It is legal to use the directive in
1090 the following modes: 6502, Tom, Jerry, OP, 56001 and 680x0 (only with -fr switch).
1091 Especially for the 56001 mode the *location* field **must** be prefixed with the
1092 intended section (*X:*, *Y:*, *P:* or *L:*).
1099 These directives control the optimisations that rmac applies to the source
1100 automatically. Each directive is applied immediately from the line encountered
1101 onwards. So it is possible to turn specific optimisations on and off globally
1102 (when placed at the start of the first file) or locally (by turning desired
1103 optimisations on and off at certain parts of the source). For a list of the
1104 optimisations (*n*) available please consult the table in section `The Command Line`_.
1106 **all**, as expected, turns all available optimisations on or off. An exception to this
1107 is *o10*/*op* as this is not an optimisation that should be turned on unless the user
1108 absolutely needs it.
1110 Lastly, as a "creature comfort" feature, if the first column of any line is prefixed
1111 with an exclamation mark (*!*) then for that line all optimisations are turned off.
1113 **.abs** [*location*]
1115 Start an absolute section, beginning with the specified location (or zero, if
1116 no location is specified). An absolute section is much like BSS, except that
1117 locations declared with .ds are based absolute. This directive is useful for
1118 declaring structures or hardware locations.
1119 For example, the following equates:
1129 could be as easily defined as:
1140 Another interesting example worth mentioning is the emulation of "C"'s "union" keyword
1141 using *.abs*. For example, the following "C" code:
1151 union { int spf_em_colour; int spf_emx_colour; };
1152 union { int spf_em_psmask[16]; int spf_emx_colouropt; };
1155 can be expressed as:
1160 *-------------------------------------------------------*
1161 spf_w: ds.w 1 ;<- common
1166 *-------------------------------------------------------*
1168 spf_em_colour: ds.l 1 ;<- union #1
1169 spf_em_psmask: ds.l 16
1170 *-------------------------------------------------------*
1174 spf_emx_colour: ds.l 1 ;<- union #2
1175 spf_emx_colouropt: ds.l 1
1176 spf_emx_psmask: ds.l 16
1177 spf_emx_psmaskopt: ds.l 16
1180 ;*-------------------------------------------------------*
1182 move #spf_em_colour,d0
1183 move #spf_emx_colour,d0
1185 In this example, *spf_em_colour* and *spf_emx_colour* will have the same value.
1187 **.comm** *symbol*, *expression*
1189 Specifies a label and the size of a common region. The label is made global,
1190 thus confined symbols cannot be made common. The linker groups all common
1191 regions of the same name; the largest size determines the real size of the
1192 common region when the file is linked.
1194 **.ccdef** *expression*
1196 Allows you to define names for the condition codes used by the JUMP
1197 and JR instructions for GPU and DSP code. For example:
1203 jump Always,(r3) ; 'Always' is actually 0
1205 **.ccundef** *regname*
1207 Undefines a register name (regname) previously assigned using the
1208 .CCDEF directive. This is only implemented in GPU and DSP code
1211 **.dc.i** *expression*
1213 This directive generates long data values and is similar to the DC.L
1214 directive, except the high and low words are swapped. This is provided
1215 for use with the GPU/DSP MOVEI instruction.
1217 **.dc**\ [.\ *size*] *expression* [, *expression*...]
1219 Deposit initialized storage in the current section. If the specified size is word
1220 or long, the assembler will execute a .even before depositing data. If the size
1221 is .b, then strings that are not part of arithmetic expressions are deposited
1222 byte-by-byte. If no size is specified, the default is .w. This directive cannot be
1223 used in the BSS section.
1225 **.dcb**\ [.\ *size*] *expression1*, *expression2*
1227 Generate an initialized block of *expression1* bytes, words or longwords of the
1228 value *expression2*. If the specified size is word or long, the assembler will
1229 execute .even before generating data. If no size is specified, the default is **.w**.
1230 This directive cannot be used in the BSS section.
1232 **.ds**\ [.\ *size*] *expression*
1234 Reserve space in the current segment for the appropriate number of bytes,
1235 words or longwords. If no size is specified, the default size is .w. If the size
1236 is word or long, the assembler will execute .even before reserving space.
1240 Switch to Jaguar DSP assembly mode. This directive must be used
1241 within the TEXT or DATA segments.
1243 **.init**\ [.\ *size*] [#\ *expression*,]\ *expression*\ [.\ *size*] [,...]
1245 Generalized initialization directive. The size specified on the directive becomes
1246 the default size for the rest of the line. (The "default" default size is **.w**.) A
1247 comma-seperated list of expressions follows the directive; an expression may be
1248 followed by a size to override the default size. An expression may be preceeded
1249 by a sharp sign, an expression and a comma, which specifies a repeat count to
1250 be applied to the next expression. For example:
1254 .init.l -1, 0.w, #16,'z'.b, #3,0, 11.b
1256 will deposit a longword of -1, a word of zero, sixteen bytes of lower-case 'z',
1257 three longwords of zero, and a byte of 11.
1259 No auto-alignment is performed within the line, but a **.even** is done once
1260 (before the first value is deposited) if the default size is word or long.
1262 **.cargs** [#\ *expression*,] *symbol*\ [.\ *size*] [, *symbol*\ [.\ *size*].. .]
1264 Compute stack offsets to C (and other language) arguments. Each symbol is
1265 assigned an absolute value (like equ) which starts at expression and increases
1266 by the size of each symbol, for each symbol. If the expression is not supplied,
1267 the default starting value is 4. For example:
1271 .cargs #8, .fileliams.1, .openMode, .butPointer.l
1273 could be used to declare offsets from A6 to a pointer to a filename, a word
1274 containing an open mode, and a pointer to a buffer. (Note that the symbols
1275 used here are confined). Another example, a C-style "string-length" function,
1276 could be written as:
1280 _strlen:: .cargs .string ; declare arg
1281 move.l .string(sp),a0 ; a0 -> string
1282 moveq #-1,d0 ; initial size = -1
1283 .1: addq.1 #1,d0 ; bump size
1284 tst.b (a0)+ ; at end of string?
1285 bne .1 ; (no -- try again)
1286 rts ; return string length
1288 **.error** ["*string*"]
1290 Aborts the build, optionally printing a user defined string. Can be useful
1291 inside conditional assembly blocks in order to catch errors. For example:
1295 .if ^^defined JAGUAR
1296 .error "TOS cannot be built on Jaguar, don't be silly"
1301 End the assembly. In an include file, end the include file and resume assembling
1302 the superior file. This statement is not required, nor are warning messages
1303 generated if it is missing at the end of a file. This directive may be used inside
1304 conditional assembly, macros or **.rept** blocks.
1306 **.equr** *expression*
1308 Allows you to name a register. For example:
1315 add ClipW,r0 ; ClipW actually is r19
1317 **.if** *expression*
1323 Start a block of conditional assembly. If the expression is true (non-zero) then
1324 assemble the statements between the .if and the matching **.endif** or **.else**.
1325 If the expression is false, ignore the statements unless a matching .else is
1326 encountered. Conditional assembly may be nested to any depth.
1328 It is possible to exit a conditional assembly block early from within an include
1329 file (with **end**) or a macro (with **endm**).
1331 **.iif** *expression*, *statement*
1333 Immediate version of **.if**. If the expression is true (non-zero) then the state-
1334 ment, which may be an instruction, a directive or a macro, is executed. If
1335 the expression is false, the statement is ignored. No **.endif** is required. For
1340 .iif age < 21, canDrink = 0
1341 .iif weight > 500, dangerFlag = 1
1342 .iif !(^^defined DEBUG), .include dbsrc
1344 **.macro** *name* [*formal*, *formal*,...]
1350 Define a macro called name with the specified formal arguments. The macro
1351 definition is terminated with a **.endm** statement. A macro may be exited early
1352 with the .exitm directive. See the chapter on `Macros`_ for more information.
1354 **.undefmac** *macroName* [, *macroName*...]
1356 Remove the macro-definition for the specified macro names. If reference is
1357 made to a macro that is not defined, no error message is printed and the name
1360 **.rept** *expression*
1364 The statements between the **.rept** and **.endr** directives will be repeated *expression*
1365 times. If the expression is zero or negative, no statements will be
1366 assembled. No label may appear on a line containing either of these directives.
1368 **.globl** *symbol* [, *symbol*...]
1370 **.extern** *symbol* [, *symbol*...]
1372 Each symbol is made global. None of the symbols may be confined symbols
1373 (those starting with a period). If the symbol is defined in the assembly, the
1374 symbol is exported in the object file. If the symbol is undefined at the end
1375 of the assembly, and it was referenced (i.e. used in an expression), then the
1376 symbol value is imported as an external reference that must be resolved by the
1377 linker. The **.extern** directive is merely a synonym for **.globl**.
1379 **.include** "*file*"
1381 Include a file. If the filename is not enclosed in quotes, then a default extension
1382 of "**.s**" is applied to it. If the filename is quoted, then the name is not changed
1385 Note: If the filename is not a valid symbol, then the assembler will generate an
1386 error message. You should enclose filenames such as "**atari.s**" in quotes,
1387 because such names are not symbols.
1389 If the include file cannot be found in the current directory, then the directory
1390 search path, as specified by -i on the commandline, or' by the 'RMACPATH'
1391 enviroment string, is traversed.
1393 **.incbin** "*file*" [, [*size*], [*offset*]]
1395 Include a file as a binary. This can be thought of a series of **dc.b** statements
1396 that match the binary bytes of the included file, inserted at the location of the
1397 directive. The directive is not allowed in a BSS section. Optional parameters
1398 control the amount of bytes to be included and offset from the start of the file.
1399 All the following lines are valid:
1402 .incbin "test.bin" ; Include the whole file
1403 .incbin "test.bin",,$30 ; Skip the first 48 bytes
1404 .incbin "test.bin",$70,$30 ; Include $70 bytes starting at offset $30
1405 .incbin "test.bin",$48 ; Include the file starting at offset 48 till the end
1406 .incbin "test.bin",, ; Include the whole file
1410 Issue a page eject in the listing file.
1412 **.title** "*string*"
1414 **.subttl** [-] "*string*"
1416 Set the title or subtitle on the listing page. The title should be specified on
1417 the the first line of the source program in order to take effect on the first page.
1418 The second and subsequent uses of **.title** will cause page ejects. The second
1419 and subsequent uses of .subttl will cause page ejects unless the subtitle string
1420 is preceeded by a dash (-).
1426 Enable or disable source code listing. These directives increment and decrement
1427 an internal counter, so they may be appropriately nested. They have no effect
1428 if the **-l** switch is not specified on the commandline.
1432 This directive provides unstructured flow of control within a macro definition.
1433 It will transfer control to the line of the macro containing the specified goto
1434 label. A goto label is a symbol preceeded by a colon that appears in the first
1435 column of a source line within a macro definition:
1439 where the label itself can be any valid symbol name, followed immediately by
1440 whitespace and a valid source line (or end of line). The colon **must** appear in
1443 The goto-label is removed from the source line prior to macro expansion -
1444 to all intents and purposes the label is invisible except to the .goto directive
1445 Macro expansion does not take place within the label.
1447 For example, here is a silly way to count from 1 to 10 without using **.rept**:
1455 iif count <= 10, goto loop
1460 Switch to Jaguar GPU assembly mode. This directive must be used
1461 within the TEXT or DATA segments.
1465 No. Just... no. Don't ask about it. Ever.
1467 **.prgflags** *value*
1469 Sets ST executable .PRG field *PRGFLAGS* to *value*. *PRGFLAGS* is a bit field defined as follows:
1471 ============ ====== =======
1472 Definition Bit(s) Meaning
1473 ============ ====== =======
1474 PF_FASTLOAD 0 If set, clear only the BSS area on program load, otherwise clear the entire heap.
1475 PF_TTRAMLOAD 1 If set, the program may be loaded into alternative RAM, otherwise it must be loaded into standard RAM.
1476 PF_TTRAMMEM 2 If set, the program's Malloc() requests may be satisfied from alternative RAM, otherwise they must be satisfied from standard RAM.
1477 -- 3 Currently unused.
1478 See left. 4 & 5 If these bits are set to 0 (PF_PRIVATE), the processes' entire memory space will be considered private (when memory protection is enabled).If these bits are set to 1 (PF_GLOBAL), the processes' entire memory space will be readable and writable by any process (i.e. global).If these bits are set to 2 (PF_SUPERVISOR), the processes' entire memory space will only be readable and writable by itself and any other process in supervisor mode.If these bits are set to 3 (PF_READABLE), the processes' entire memory space will be readable by any application but only writable by itself.
1479 -- 6-15 Currently unused.
1480 ============ ====== =======
1482 **.regequ** *expression*
1483 Essentially the same as **.EQUR.** Included for compatibility with the GASM
1487 Essentially the same as **.EQURUNDEF.** Included for compatibility with
1496 All of the standard Motorola 68000 mnemonics and addressing modes are supported;
1497 you should refer to **The Motorola M68000 Programmer's Reference Manual**
1498 for a description of the instruction set and the allowable addressing modes for each
1499 instruction. With one major exception (forward branches) the assembler performs
1500 all the reasonable optimizations of instructions to their short or address register
1503 Register names may be in upper or lower case. The alternate forms ``R0`` through
1504 ``R15`` may be used to specify ``D0`` through ``A7``. All register names are keywords, and
1505 may not be used as labels or symbols. None of the 68010 or 68020 register names
1506 are keywords (but they may become keywords in the future).
1511 ===================================== ===========================================
1512 Assembler Syntax Description
1513 ===================================== ===========================================
1514 *Dn* Data register direct
1515 *An* Address register direct
1516 (*An*) Address register indirect
1517 (*An*)+ Address register indirect postincrement
1518 -(*An*) Address register indirect predecrement
1519 *disp*\ (*An*) Address register indirect with displacement
1520 *bdisp*\ (*An*, *Xi*\ [.\ *size*]) Address register indirect indexed
1521 *abs*.w Absolute short
1522 *abs* Absolute (long or short)
1523 *abs*.l Forced absolute long
1524 *disp*\ (PC) Program counter with displacement
1525 *bdisp*\ (PC, *Xi*\ ) Program counter indexed
1527 ===================================== ===========================================
1529 `68020+ Addressing Modes`_
1530 ''''''''''''''''''''''''''
1532 The following addressing modes are only valid for 68020 and newer CPUs. In these
1533 modes most of the parameters like Base Displacement (**bd**), Outer Displacement
1534 (**od**), Base Register (**An**) and Index Register (**Xn**) can be omitted. RMAC
1535 will detect this and *suppress* the registers in the produced code.
1538 use a special syntax to denote register suppression like **Zan** to suppress the Base
1539 Register and **Rin** to suppress the Index Register. RMAC has no support for this
1540 behaviour nor needs it to suppress registers.
1542 In addition, other assemblers will allow reordering of the parameters (for example
1543 ([*An*,\ *bd*])). This is not allowed in RMAC.
1545 Also noteworthy is that the Index Register can be an address or data register.
1547 To avoid internal confusion the 68040/68060 registers *DC*, *IC* and *BC* are named
1548 *DC40*, *IC40* and *BC40* respectively.
1550 ====================================================== =============================================================
1551 Assembler Syntax Description
1552 ====================================================== =============================================================
1553 *bd*\ (*An*, *Xi*\ [.\ *size*][*\*scale*]) Address register indirect indexed
1554 ([*bd*,\ *An*],\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Register indirect preindexed with outer displacement
1555 ([*bd*,\ *An*,\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Register indirect postindexed with outer displacement
1556 ([*bd*,\ *PC*],\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Program counter indirect preindexed with outer displacement
1557 ([*bd*,\ *PC*,\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Program counter indirect postindexed with outer displacement
1558 ====================================================== =============================================================
1562 Since RMAC is a one pass assembler, forward branches cannot be automatically
1563 optimized to their short form. Instead, unsized forward branches are assumed to
1564 be long. Backward branches are always optimized to the short form if possible.
1566 A table that lists "extra" branch mnemonics (common synonyms for the Motorola
1567 defined mnemonics) appears below.
1569 `Linker Constraints`_
1570 '''''''''''''''''''''
1571 It is not possible to make an external reference that will fix up a byte. For example:
1576 move.l frog(pc,d0),d1
1578 is illegal (and generates an assembly error) when frog is external, because the
1579 displacement occupies a byte field in the 68000 offset word, which the object file
1584 ============== ========
1585 Alternate name Becomes:
1586 ============== ========
1596 ============== ========
1598 `Optimizations and Translations`_
1599 '''''''''''''''''''''''''''''''''
1600 The assembler provides "creature comforts" when it processes 68000 mnemonics:
1602 * **CLR.x An** will really generate **SUB.x An,An**.
1604 * **ADD**, **SUB** and **CMP** with an address register will really generate **ADDA**,
1605 **SUBA** and **CMPA**.
1607 * The **ADD**, **AND**, **CMP**, **EOR**, **OR** and **SUB** mnemonics with immediate
1608 first operands will generate the "I" forms of their instructions (**ADDI**, etc.) if
1609 the second operand is not register direct.
1611 * All shift instructions with no count value assume a count of one.
1613 * **MOVE.L** is optimized to **MOVEQ** if the immediate operand is defined and
1614 in the range -128...127. However, **ADD** and **SUB** are never translated to
1615 their quick forms; **ADDQ** and **SUBQ** must be explicit.
1617 * All optimisations are controllable using the **.opt** directive. Refer to its
1618 description in section `Directives`_.
1620 * All optimisations are turned off for any source line that has an exclamation mark
1621 (*!*) on their first column.
1623 * Optimisation switch 11 is turned on by default for compatibility with the
1624 Motorola reference 56001 DSP assembler.
1625 All other levels are off by default. (refer to section `The Command Line`_
1626 for a description of all the switches).
1628 * Optimisation warnings are off by default. Invoke RMAC with the *-s* switch to
1629 turn on warnings in console and listing output.
1631 * In GPU/DSP code sections, you can use JUMP (Rx) in place of JUMP T, (Rx) and JR
1632 (Rx) in place of JR T,(Rx).
1634 * RMAC tests all GPU/DSP restrictions and corrects them wherever possible (such as
1635 inserting a NOP instruction when needed).
1637 * The *(Rx+N)* addressing mode for GPU/DSP instructions is optimized to *(Rx)*
1642 `Macro declaration`_
1643 ''''''''''''''''''''
1644 A macro definition is a series of statements of the form:
1647 .macro name [ formal-arg, ...]
1651 statements making up the macro body
1657 The name of the macro may be any valid symbol that is not also a 68000 instruction
1658 or an assembler directive. (The name may begin with a period - macros cannot
1659 be made confined the way labels or equated symbols can be). The formal argument
1660 list is optional; it is specified with a comma-seperated list of valid symbol names.
1661 Note that there is no comma between the name of the macro and the name of the
1662 first formal argument. It is not advised to begin an argument name with a numeric
1665 A macro body begins on the line after the **.macro** directive. All instructions
1666 and directives, except other macro definitions, are legal inside the body.
1668 The macro ends with the **.endm** statement. If a label appears on the line with
1669 this directive, the label is ignored and a warning is generated.
1671 `Parameter Substitution`_
1672 '''''''''''''''''''''''''
1673 Within the body, formal parameters may be expanded with the special forms:
1679 The second form (enclosed in braces) can be used in situations where the characters
1680 following the formal parameter name are valid symbol continuation characters. This
1681 is usually used to force concatentation, as in:
1686 \(godzilla}vs\{reagan}
1688 The formal parameter name is terminated with a character that is not valid in
1689 a symbol (e.g. whitespace or puncuation); optionally, the name may be enclosed in
1690 curly-braces. The names must be symbols appearing on the formal argument list,
1691 or a single decimal digit (``\1`` corresponds to the first argument, ``\2`` to the second,
1692 ``\9`` to the ninth, and ``\0`` to the tenth). It is possible for a macro to have more than
1693 ten formal arguments, but arguments 11 and on must be referenced by name, not
1696 Other special forms are:
1698 ============ ================================================
1699 Special Form Description
1700 ============ ================================================
1701 ``\\`` a single "\",
1702 ``\~`` a unique label of the form "Mn"
1703 ``\#`` the number of arguments actually specified
1704 ``\!`` the "dot-size" specified on the macro invocation
1705 ``\?name`` conditional expansion
1706 ``\?{name}`` conditional expansion
1707 ============ ================================================
1709 The last two forms are identical: if the argument is specified and is non-empty, the
1710 form expands to a "1", otherwise (if the argument is missing or empty) the form
1713 The form "``\!``" expands to the "dot-size" that was specified when the macro
1714 was invoked. This can be used to write macros that behave differently depending
1715 on the size suffix they are given, as in this macro which provides a synonym for the
1720 .macro deposit value
1723 deposit.b 1 ; byte of 1
1724 deposit.w 2 ; word of 2
1725 deposit.l 3 ; longvord of 3
1726 deposit 4 ; word of 4 (no explicit size)
1730 A previously-defined macro is called when its name appears in the operation field of
1731 a statement. Arguments may be specified following the macro name; each argument
1732 is seperated by a comma. Arguments may be empty. Arguments are stored for
1733 substitution in the macro body in the following manner:
1735 * Numbers are converted to hexadecimal.
1737 * All spaces outside strings are removed.
1739 * Keywords (such as register names, dot sizes and "^^" operators) are converted
1742 * Strings are enclosed in double-quote marks (").
1744 For example, a hypothetical call to the macro "``mymacro``", of the form:
1745 ``mymacro A0, , 'Zorch' / 32, "^^DEFINED foo, , , tick tock``
1747 will result in the translations:
1749 ======== ================= =================================================
1750 Argument Expansion Comment
1751 ======== ================= =================================================
1752 ``\1`` ``a0`` "``A0``" converted to lower-case
1754 ``\3`` ``"Zorch"/$20`` "``Zorch``" in double-quotes, 32 in hexadecimal
1755 ``\4`` ``^^defined foo`` "``^^DEFINED``" converted to lower-case
1758 ``\7`` ``ticktock`` spaces removed (note concatenation)
1759 ======== ================= =================================================
1761 The **.exitm** directive will cause an immediate exit from a macro body. Thus
1762 the macro definition:
1767 .iif !\?source, .exitm ; exit if source is empty
1768 move \source,d0 ; otherwise, deposit source
1771 will not generate the move instruction if the argument **"source"** is missing from
1772 the macro invocation.
1774 The **.end**, **.endif** and **.exitm** directives all pop-out of their include levels
1775 appropriately. That is, if a macro performs a **.include** to include a source file, an
1776 executed **.exitm** directive within the include-file will pop out of both the include-file
1779 Macros may be recursive or mutually recursive to any level, subject only to
1780 the availability of memory. When writing recursive macros, take care in the coding
1781 of the termination condition(s). A macro that repeatedly calls itself will cause the
1782 assembler to exhaust its memory and abort the assembly.
1787 The Gemdos macro is used to make file system calls. It has two parameters, a
1788 function number and the number of bytes to clean off the stack after the call. The
1789 macro pushes the function number onto the stack and does the trap to the file
1790 system. After the trap returns, conditional assembly is used to choose an addq or
1791 an **add.w** to remove the arguments that were pushed.
1795 .macro Gemdos trpno, clean
1796 move.w #\trpno,-(sp) ; push trap number
1797 trap #1 ; do GEMDOS trap
1799 addq #\clean,sp ; clean-up up to 8 bytes
1801 add.w #\clean,sp ; clean-up more than 8 bytes
1805 The Fopen macro is supplied two arguments; the address of a filename, and
1806 the open mode. Note that plain move instructions are used, and that the caller of
1807 the macro must supply an appropriate addressing mode (e.g. immediate) for each
1812 .macro Fopen file, mode
1813 movs.w \mode,-(sp) ;push open mode
1814 move.1 \file,-(sp) ;push address of tile name
1815 Gemdos $3d,8 ;do the GEMDOS call
1818 The **String** macro is used to allocate storage for a string, and to place the
1819 string's address somewhere. The first argument should be a string or other expres-
1820 sion acceptable in a dc.b directive. The second argument is optional; it specifies
1821 where the address of the string should be placed. If the second argument is omitted,
1822 the string's address is pushed onto the stack. The string data itself is kept in the
1827 .macro String str,loc
1828 .if \?loc ; if loc is defined
1829 move.l #.\~,\loc ; put the string's address there
1831 pea .\~ ; push the string's address
1833 .data ; put the string data
1834 .\~: dc.b \str,0 ; in the data segment
1835 .text ; and switch back to the text segment
1838 The construction "``.\~``" will expand to a label of the form "``.M``\ *n*" (where *n* is
1839 a unique number for every macro invocation), which is used to tag the location of
1840 the string. The label should be confined because the macro may be used along with
1841 other confined symbols.
1843 Unique symbol generation plays an important part in the art of writing fine
1844 macros. For instance, if we needed three unique symbols, we might write "``.a\~``",
1845 "``.b\~``" and "``.c\~``".
1849 Repeat-blocks provide a simple iteration capability. A repeat block allows a range
1850 of statements to be repeated a specified number of times. For instance, to generate
1851 a table consisting of the numbers 255 through 0 (counting backwards) you could
1856 .count set 255 ; initialize counter
1857 .rept 256 ; repeat 256 times:
1858 dc.b .count ; deposit counter
1859 .count set .count - 1 ; and decrement it
1860 .endr ; (end of repeat block)
1862 Repeat blocks can also be used to duplicate identical pieces of code (which are
1863 common in bitmap-graphics routines). For example:
1867 .rept 16 ; clear 16 words
1868 clr.w (a0)+ ; starting at AO
1871 `Jaguar GPU/DSP Mode`_
1872 ======================
1874 RMAC will generate code for the Atari Jaguar GPU and DSP custom RISC (Reduced
1875 Instruction Set Computer) processors. See the Atari Jaguar Software reference Manual - Tom
1876 & Jerry for a complete listing of Jaguar GPU and DSP assembler mnemonics and addressing
1881 The following condition codes for the GPU/DSP JUMP and JR instructions are built-in:
1885 CC (Carry Clear) = %00100
1886 CS (Carry Set) = %01000
1889 NE (Not Equal) = %00001
1891 HI (Higher) = %00101
1894 `Jaguar Object Processor Mode`_
1895 ===============================
1900 An assembler to generate object lists for the Atari Jaguar's Object processor.
1906 To really utilize the OP properly, it needs an assembler. Otherwise, what
1907 happens is you end up writing an assembler in your code to assemble the OP
1908 list, and that's a real drag--something that *should* be handled by a proper
1913 ''''''''''''''''''''
1915 The OP assembler works similarly to the RISC assembler; to enter the OP
1916 assembler, you put the .objproc directive in your code (N.B.: like the RISC
1917 assembler, it only works in a TEXT or DATA section). From there, you build
1918 the OP list how you want it and go from there. A few caveats: you will want
1919 to put a .org directive at the top of your list, and labels that you want to
1920 be able to address in 68xxx code (for moving from a data section to an
1921 address where it will be executed by the OP, for example) should be created
1925 `What are the opcodes?`_
1926 ''''''''''''''''''''''''
1928 They are **bitmap**, **scbitmap**, **gpuobj**, **branch**, **stop**, **nop**, and **jump**. **nop** and **jump**
1929 are psuedo-ops, they are there as a convenience to the coder.
1932 `What are the proper forms for these opcodes?`_
1933 '''''''''''''''''''''''''''''''''''''''''''''''
1935 They are as follows:
1937 **bitmap** *data addr*, *xloc*, *yloc*, *dwidth*, *iwidth*, *iheight*, *bpp*,
1938 *pallete idx*, *flags*, *firstpix*, *pitch*
1940 **scbitmap** *data addr*, *xloc*, *yloc*, *dwidth*, *iwidth*, *iheight*,
1941 *xscale*, *yscale*, *remainder*, *bpp*, *pallete idx*,
1942 *flags*, *firstpix*, *pitch*
1944 **gpuobj** *line #*, *userdata* (bits 14-63 of this object)
1946 **branch** VC *condition (<, =, >)* *line #*, *link addr*
1948 **branch** OPFLAG, *link addr*
1950 **branch** SECHALF, *link addr*
1956 **jump** *link addr*
1958 Note that the *flags* field in bitmap and scbitmap objects consist of the
1959 following: **REFLECT**, **RMW**, **TRANS**, **RELEASE**. They can be in any order (and
1960 should be separated by whitespace **only**), and you can only put a maximum of
1961 four of them in. Further note that with bitmap and scbitmap objects, all the
1962 parameters after *data addr* are optional--if they are omitted, they will
1963 use defaults (mostly 0, but 1 is the default for pitch). Also, in the
1964 scbitmap object, the *xscale*, *yscale*, and *remainder* fields can be
1965 floating point constants/expressions. *data addr* can refer to any address
1966 defined (even external!) and the linker (rln v1.6.0 or greater) will
1967 properly fix up the address.
1973 Pretty much what you expect. It's beyond the scope of this little note to
1974 explain the Jaguar's Object Processor and how it operates, so you'll have to
1975 seek explanations for how they work elsewhere.
1978 `Why do I want to put a *.org* directive at the top of my list?`_
1979 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
1981 You want to put a *.org* directive at the top of your list because otherwise
1982 the assembler will not know where in memory the object list is supposed
1983 go--then when you move it to its destination, the object link addresses will
1984 all be wrong and it won't work.
1987 `Why would I copy my object list to another memory location?`_
1988 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
1990 Simple: because the OP destroys the list as it uses it to render the screen.
1991 If you don't keep a fresh copy stashed away somewhere to refresh it before
1992 the next frame is rendered, what you see on the screen will not be what you
1993 expect, as the OP has scribbled all over it!
1996 `Does the assembler do anything behind my back?`_
1997 '''''''''''''''''''''''''''''''''''''''''''''''''
1999 Yes, it will emit **NOP** s to ensure that bitmaps and scbitmaps are on proper
2000 memory boundaries, and fixup link addresses as necessary. This is needed
2001 because of a quirk in how the OP works (it ORs constants on the address
2002 lines to get the phrases it needs and if they are not zeroes, it will fail
2003 in bizarre ways). It will also set all *ypos* constants on the correct
2004 half-line (as that's how the OP views them).
2007 `Why can't I define the link addresses for all the objects?`_
2008 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
2010 You really, *really* don't want to do this. Trust me on this one.
2012 `How about an example of an object list?`_
2013 ''''''''''''''''''''''''''''''''''''''''''
2021 objects: ; This is the label you will use to address this in 68K code
2022 .objproc ; Engage the OP assembler
2023 .org objList ; Tell the OP assembler where the list will execute
2025 branch VC < 69, .stahp ; Branch to the STOP object if VC < 69
2026 branch VC > 241, .stahp ; Branch to the STOP object if VC > 241
2027 bitmap bRAM, 22, 70, 24, 24, 22, 4
2028 bitmap bRAM, 20+96+96, 70, 24, 24, 22, 4, 0, REFLECT
2029 scbitmap tms, 20, 70, 1, 1, 8, 3.0, 3.0, 2.9999, 0, 0, TRANS
2030 scbitmap tmsShadow, 23, 73, 1, 1, 8, 3.0, 3.0, 2.9999, 0, 3, TRANS
2031 bitmap sbRelBM, 30, 108, 3, 3, 8, 0, 1, TRANS
2032 bitmap txt1BM, 46, 132, 3, 3, 8, 0, 2, TRANS
2033 bitmap txt2BM, 46, 148, 3, 3, 8, 0, 2, TRANS
2034 bitmap txt3BM, 22, 164, 3, 3, 8, 0, 2, TRANS
2045 RMAC fully supports Motorola's DSP56001 as used on the Atari Falcon and can output
2046 binary code in the two most popular formats: *.lod* (ASCII dump, supported by the
2047 Atari Falcon XBIOS) and *.p56* (binary equivalent of *.lod*)
2049 `Differences from Motorola's assembler`_
2050 ''''''''''''''''''''''''''''''''''''''''
2052 - Motorola's assembler aliases **and #xxx,reg** with **andi #xxx,reg** and can
2053 distinguish between the two. rmac needs the user to be explicit and will
2054 generate an error if the programmer tries to use syntax from one instruction
2056 - Similarly Motorola's assembler can alias **move** with **movec**, **movep**
2057 and **movem**. rmac also not accept such aliasing and generate an error.
2058 - Motorola's assembler uses the underscore character (*_*) to define local
2059 labels. In order for rmac to maintain a uniform syntax across all platforms,
2060 such labels will not be treated as local.
2061 - Macros syntax is different from Motorola's assembler. This includes local
2062 labels inside macros. The user is encouraged to study the `Macros`_ section
2063 and compare syntactical differences.
2064 - Motorola's assembler allows reordering of addressing modes **x:**, **x:r**,
2065 **r:y**, **x:y**. rmac will only accept syntax as is defined on the reference
2067 - In **L:** section a dc value cannot be 12 hex digits like Motorola's assmebler.
2068 Instead, the value needs to be split into two parts separated by **:**.
2072 RMAC will generate code for the MOS 6502 microprocessor. This chapter
2073 describes extra addressing modes and directives used to support the 6502.
2075 As the 6502 object code is not linkable (currently there is no linker) external
2076 references may not be made. (Nevertheless, RMAC may reasonably be used for
2077 large assemblies because of its blinding speed.)
2079 `6502 Addressing Modes`_
2080 ''''''''''''''''''''''''
2081 All standard 6502 addressing modes are supported, with the exception of the
2082 accumulator addressing form, which must be omitted (e.g. "ror a" becomes "ror").
2083 Five extra modes, synonyms for existing ones, are included for compatibility with
2084 the Atari Coinop assembler.
2086 ============== ========================================
2087 *empty* implied or accumulator (e.g. tsx or ror)
2088 *expr* absolute or zeropage
2090 #<\ *expr* immediate low byte of a word
2091 #>\ *expr* immediate high byte of a word
2092 (*expr*,x) indirect X
2093 (*expr*),y indirect Y
2097 @\ *expr*\ (x) indirect X
2098 @\ *expr*\ (y) indirect Y
2100 x,\ *expr* indexed X
2101 y,\ *expr* indexed Y
2102 ============== ========================================
2107 This directive enters the 6502 section. The location counter is undefined, and
2108 must be set with ".org" before any code can be generated.
2110 The "``dc.w``" directive will produce 6502-format words (low byte first). The
2111 68000's reserved keywords (``d0-d7/a0-a7/ssp/usp`` and so on) remain reserved
2112 (and thus unusable) while in the 6502 section. The directives **globl**, **dc.l**,
2113 **dcb.l**, **text**, **data**, **bss**, **abs**, **even** and **comm** are illegal in the 6502 section.
2114 It is permitted, though probably not useful, to generate both 6502 and 68000
2115 code in the same object file.
2117 This directive leaves the 6502 segment and returns to the 68000's text segment.
2118 68000 instructions may be assembled as normal.
2120 This directive sets the value of the location
2121 counter (or **pc**) to location, an expression that must be defined, absolute, and
2126 It is possible to assemble "beyond" the microprocessor's 64K address space, but
2127 attempting to do so will probably screw up the assembler. DO NOT attempt
2128 to generate code like this:
2137 the third NOP in this example, at location $10000, may cause the assembler
2138 to crash or exhibit spectacular schizophrenia. In any case, RMAC will give
2139 no warning before flaking out.
2141 `6502 Object Code Format`_
2142 ''''''''''''''''''''''''''
2143 Traditionally Madmac had a very kludgy way of storing object files. This has been
2144 replaced with a more standard *.exe* (or *.com* or *.xex* if you prefer). Briefly,
2145 the *.exe* format consists of chunks of this format (one after the other):
2150 00-01 $FFFF - Indicates a binary load file. Mandatory for first segment, optional for any other segment
2151 02-03 Start Address. The segment will load at this address
2152 04-05 End Address. The last byte to load for this segment
2153 06-.. The actual segment data to load (End Address-Start Address + 1 bytes)
2158 `When Things Go Wrong`_
2159 '''''''''''''''''''''''
2160 Most of RMAC's error messages are self-explanatory. They fall into four classes:
2161 warnings about situations that you (or the assembler) may not be happy about,
2162 errors that cause the assembler to not generate object files, fatal errors that cause
2163 the assembler to abort immediately, and internal errors that should never happen.\ [3]_
2165 You can write editor macros (or sed or awk scripts) to parse the error messages
2166 RMAC generates. When a message is printed, it is of the form:
2168 "*filename*" , ``line`` *line-number*: *message*
2170 The first element, a filename enclosed in double quotes, indicates the file that generated
2171 the error. The filename is followed by a comma, the word "``line``", and a line
2172 number, and finally a colon and the text of the message. The filename "**(\*top\*)**"
2173 indicates that the assembler could not determine which file had the problem.
2175 The following sections list warnings, errors and fatal errors in alphabetical
2176 order, along with a short description of what may have caused the problem.
2178 .. [3] If you come across an internal error, we would appreciate it if you would contact the rmac development team and let us know about the problem.
2182 **bad backslash code in string**
2183 You tried to follow a backslash in a string with a character that the assembler
2184 didn't recognize. Remember that RMAC uses a C-style escape system in
2187 You specified a label before a macro, **rept** or **endm** directive. The assembler
2188 is warning you that the label will not be defined in the assembly.
2189 **unoptimized short branch**
2190 This warning is only generated if the -s switch is specified on the command
2191 line. The message refers to a forward, unsized long branch that you could have
2198 As a result of previous errors, the assembler cannot continue processing. The
2199 assembly is aborted.
2200 **line too long as a result of macro expansion**
2201 When a source line within a macro was expanded, the resultant line was too
2202 long for RMAC (longer than 200 characters or so).
2205 **memory exhausted**
2206 The assembler ran out of memory. You should (1) split up your source files
2207 and assemble them seperately, or (2) if you have any ramdisks or RAM-resident
2208 programs (like desk accessories) decrease their size so that the assembler has
2209 more RAM to work with. As a rule of thumb, pure 68000 code will use up to
2210 twice the number of bytes contained in the source files, whereas 6502 code will
2211 use 64K of ram right away, plus the size of the source files. The assembler itself
2212 uses about 80K bytes. Get out your calculator...
2214 The assembler ran across an **endm** directive when it wasn't expecting to see
2215 one. The assembly is aborted. Check the nesting of your macro definitions -
2216 you probably have an extra **endm**.
2224 Syntax error in **.cargs** directive.
2226 **.comm symbol already defined**
2228 You tried to ``.comm`` a symbol that was already defined.
2230 **.init not permitted in BSS or ABS**
2232 You tried to use ``.init`` in the BSS or ABS section.
2234 **Cannot create:** *filename*
2236 The assembler could not create the indicated filename.
2238 **External quick reference**
2240 You tried to make the immediate operand of a **moveq**, **subq** or **addq** instruction external.
2242 **PC-relative expr across sections**
2244 You tried to make a PC-relative reference to a location contained in another
2247 **[bwsl] must follow '.' in symbol**
2249 You tried to follow a dot in a symbol name with something other than one of
2250 the four characters 'B', 'W', 'S' or 'L'.
2252 **addressing mode syntax**
2254 You made a syntax error in an addressing mode.
2258 One of your **.assert** directives failed!
2260 **bad (section) expression**
2262 You tried to mix and match sections in an expression.
2264 **bad 6502 addressing mode**
2266 The 6502 mnemonic will not work with the addressing mode you specified.
2270 There's a syntax error in the expression you typed.
2272 **bad size specified**
2274 You tried to use an inappropriate size suffix for the instruction. Check your
2275 68000 manual for allowable sizes.
2279 You can't use .b (byte) mode with the **movem** instruction.
2281 **cannot .globl local symbol**
2283 You tried to make a confined symbol global or common.
2285 **cannot initialize non-storage (BSS) section**
2287 You tried to generate instructions (or data, with dc) in the BSS or ABS section.
2289 **cannot use '.b' with an address register**
2291 You tried to use a byte-size suffix with an address register. The 68000 does not
2292 perform byte-sized address register operations.
2294 **directive illegal in .6502 section**
2296 You tried to use a 68000-oriented directive in the 6502 section.
2300 The expression you typed involves a division by zero.
2302 **expression out of range**
2304 The expression you typed is out of range for its application.
2306 **external byte reference**
2308 You tried to make a byte-sized reference to an external symbol, which the
2309 object file format will not allow.
2311 **external short branch**
2313 You tried to make a short branch to an external symbol, which the linker cannot
2316 **extra (unexpected) text found after addressing mode**
2318 RMAC thought it was done processing a line, but it ran up against "extra"
2319 stuff. Be sure that any comment on the line begins with a semicolon, and check
2320 for dangling commas, etc.
2322 **forward or undefined .assert**
2324 The expression you typed after a **.assert** directive had an undefined value.
2325 Remember that RMAC is one-pass.
2327 **hit EOF without finding matching .endif**
2329 The assembler fell off the end of last input file without finding a **.endif** to
2330 match an . it. You probably forgot a **.endif** somewhere.
2332 **illegal 6502 addressing mode**
2334 The 6502 instruction you typed doesn't work with the addressing mode you
2337 **illegal absolute expression**
2339 You can't use an absolute-valued expression here.
2341 **illegal bra.s with zero offset**
2343 You can't do a short branch to the very next instruction (read your 68000
2346 **illegal byte-sized relative reference**
2348 The object file format does not permit bytes contain relocatable values; you
2349 tried to use a byte-sized relocatable expression in an immediate addressing
2352 **illegal character**
2354 Your source file contains a character that RMAC doesn't allow. (most
2355 control characters fall into this category).
2357 **illegal initialization of section**
2359 You tried to use .dc or .dcb in the BSS or ABS sections.
2361 **illegal relative address**
2363 The relative address you specified is illegal because it belongs to a different
2366 **illegal word relocatable (in .PRG mode)**
2368 You can't have anything other than long relocatable values when you're gener-
2369 ating a **.PRG** file.
2371 **inappropriate addressing mode**
2373 The mnemonic you typed doesn't work with the addressing modes you specified.
2374 Check your 68000 manual for allowable combinations.
2376 **invalid addressing mode**
2378 The combination of addressing modes you picked for the **movem** instruction
2379 are not implemented by the 68000. Check your 68000 reference manual for
2382 **invalid symbol following ^^**
2384 What followed the ^^ wasn't a valid symbol at all.
2386 **mis-nested .endr**
2388 The assembler found a **.endr** directive when it wasn't prepared to find one.
2389 Check your repeat-block nesting.
2391 **mismatched .else**
2393 The assembler found a **.else** directive when it wasn't prepared to find one.
2394 Check your conditional assembly nesting.
2396 **mismatched .endif**
2398 The assembler found a **.endif** directive when it wasn't prepared to find one.
2399 Check your conditional assembly nesting.
2405 **missing argument name**
2407 **missing close parenthesis ')'**
2409 **missing close parenthesis ']'**
2413 **missing filename**
2419 **missing symbol or string**
2421 The assembler expected to see a symbol/filename/string (etc...), but found
2422 something else instead. In most cases the problem should be obvious.
2424 **misuse of '.', not allowed in symbols**
2426 You tried to use a dot (.) in the middle of a symbol name.
2430 The expression you typed involves a modulo by zero.
2432 **multiple formal argument definition**
2434 The list of formal parameter names you supplied for a macro definition includes
2435 two identical names.
2437 **multiple macro definition**
2439 You tried to define a macro which already had a definition.
2441 **non-absolute byte reference**
2443 You tried to make a byte reference to a relocatable value, which the object file
2444 format does not allow.
2446 **non-absolute byte value**
2448 You tried to dc.b or dcb.b a relocatable value. Byte relocatable values are
2449 not permitted by the object file format.
2451 **register list order**
2453 You tried to specify a register list like **D7-D0**, which is illegal. Remember
2454 that the first register number must be less than or equal to the second register
2457 **register list syntax**
2459 You made an error in specifying a register list for a **.reg** directive or a **.movem**
2462 **symbol list syntax**
2464 You probably forgot a comma between the names of two symbols in a symbol
2465 list, or you left a comma dangling on the end of the line.
2469 This is a "catch-all" error.
2471 **undefined expression**
2473 The expression has an undefined value because of a forward reference, or an
2474 undefined or external symbol.
2476 **unimplemented directive**
2478 You have found a directive that didn't appear in the documentation. It doesn't
2481 **unimplemented mnemonic**
2485 **unknown symbol following ^^**
2487 You followed a ^^ with something other than one of the names defined, referenced
2490 **unterminated string**
2492 You specified a string starting with a single or double quote, but forgot to type
2497 The assembler had a problem writing an object file. This is usually caused by
2498 a full disk, or a bad sector on the media.