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 © 2011-2020, Reboot*
22 *All rights reserved.*
24 *Reboot Document number F00000K-001 Rev. A.*
36 This document describes RMAC, a fast macro assembler for the 68000. RMAC currently
37 runs on the any POSIX compatible platform and the Atari ST. It was initially written
38 at Atari Corporation by programmers who needed a high performance assembler
39 for their work. Then, more than 20 years later, because there was still a need for
40 such an assembler and what was available wasn't up to expectations, Subqmod
41 and eventually Reboot continued work on the freely released source, adding Jaguar
42 extensions and fixing bugs. Over time the assembler has been extended by adding
43 support for Motorola's 68020/30/40/60, 68881/2, DSP56001 CPUs as well as Atari's
44 Object Processor (OP) found on the Atari Jaguar.
46 RMAC is intended to be used by programmers who write mostly in assembly language.
47 It was not originally a back-end to a C compiler, therefore it
48 has creature comfort that are usually neglected in such back-end assemblers. It
49 supports include files, macros, symbols with limited scope, some limited control
50 structures, and other features. RMAC is also blindingly fast, another feature
51 often sadly and obviously missing in today's assemblers.\ [1]_
53 RMAC is not entirely compatible with the AS68 assembler provided with
54 the original Atari ST Developer's Kit, but most changes are minor and a few minutes
55 with an editor should allow you to assemble your current source files. If you are an
56 AS68 user, before you leap into the unknown please read the section on Notes for
59 .. [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!
65 * The distribution disk contains a file called README that you should read.
66 This file contains important nays about the contents of the distribution disk
67 and summarizes the most recent changes to the tools.
69 * Hard disk users can simply copy the executable files to their work or binary
70 directories. People with floppy disks can copy the executables to ramdisks,
71 install the assembler with the -q option, or even work right off of the floppies.
73 * You will need an editor that can produce "normal" format text files. Micro
74 Emacs will work well, as will most other commercial program editors, but not
75 most word processors (such as First Word or Microsoft Write).
77 * You will probably want to examine or get a listing of the file "ATARI.S". It
78 contains lots of definitions for the Atari ST, including BIOS variables, most
79 BIOS, XBIOS and GEMDOS traps, and line-A equates. We (or you) could
80 split the file up into pieces (a file for line-A equates, a file for hardware and
81 BIOS variables and so on), but RMAC is so fast that it doesn't matter
84 * Read the rest of the manual, especially the first two chapters on The Command Line and Using RMAC.
85 Also, `Notes for migrating from other 68000 assemblers`_ will save a lot of time and frustration in the long run.
86 The distribution disk contains example
87 programs that you can look at, assemble and modify.
92 The assembler is called "**rmac**" or "**rmac.prg**". The command line takes the form:
94 **rmac** [*switches*] [*files* ...]
96 A command line consists of any number of switches followed by the names of files
97 to assemble. A switch is specified with a dash (**-**) followed immediately by a key
98 character. Key characters are not case-sensitive, so "**-d**" is the same as "**-D**". Some
99 switches accept (or require) arguments to immediately follow the key character,
100 with no spaces in between.
102 Switch order is important. Command lines are processed from left to right in
103 one pass, and switches usually take effect when they are encountered. In general it
104 is best to specify all switches before the names of any input files.
106 If the command line is entirely empty then RMAC prints a copyright message
107 along with usage info and exit.
109 Input files are assumed to have the extension "**.s**"; if a filename has no extension
110 (i.e. no dot) then "**.s**" will be appended to it. More than one source filename may be
111 specified: the files are assembled into one object file, as if they were concatenated.
113 RMAC normally produces object code in "**file.o**" if "**file.s**" is the first
114 input filename. If the first input file is a special character device, the output name
115 is noname.o. The **-o** switch (see below) can be used change the output file name.
118 =================== ===========
120 =================== ===========
121 -dname\ *[=value]* Define symbol, with optional value.
122 -e\ *[file[.err]]* Direct error messages to the specified file.
123 -fa ALCYON output object file format (implied when **-ps** is enabled).
124 -fb BSD COFF output object file format.
125 -fe ELF output object file format.
126 -fr Absolute address. Source code is required to have one .org statement.
127 -fx Atari 800 com/exe/xex output object file format.
128 -g Generate source level debug info. Requires BSD COFF object file format.
129 -i\ *path* Set include-file directory search path.
130 -l\ *[file[prn]]* Construct and direct assembly listing to the specified file.
131 -l\ *\*[filename]* Create an output listing file without pagination.
132 -m\ *cpu* Switch CPU type
152 `tom - Jaguar GPU JRISC`
154 `jerry - Jaguar DSP JRISC`
156 -o\ *file[.o]* Direct object code output to the specified file.
157 +/~oall Turn all optimisations on/off
158 +o\ *0-30*/*p* Enable specific optimisation
159 ~o\ *0-30*/*p* Disable specific optimisation
161 `0: Absolute long adddresses to word (on by default)`
163 `1: move.l #x,Dn/An to moveq (on by default)`
165 `2: Word branches to short (on by default)`
167 `3: Outer displacement 0(An) to (An)`
171 `5: 68020+ Absolute long base/outer displacement to word`
173 `6: Convert null short branches to NOP`
175 `7: Convert clr.l Dn to moveq #0,Dn`
177 `8: Convert adda.w/l #x,Dy to addq.w/l #x,Dy`
179 `9: Convert adda.w/l #x,Dy to lea x(Dy),Dy`
181 `10: 56001 Use short format for immediate values if possible`
183 `11: 56001 Auto convert short addressing mode to long (default: on)`
185 `o30: Enforce PC relative (alternative name: op)`
187 -p Produce an executable (**.prg**) output file.
188 -ps Produce an executable (**.prg**) output file with symbols.
189 -px Produce an executable (**.prg**) output file with extended symbols.
190 -q Make RMAC resident in memory (Atari ST only).
191 -r *size* automatically pad the size of each
192 segment in the output file until the size is an integral multiple of the
193 specified boundary. Size is a letter that specifies the desired boundary.
195 `-rw Word (2 bytes, default alignment)`
199 `-rp Phrase (8 bytes)`
201 `-rd Double Phrase (16 bytes)`
203 `-rq Quad Phrase (32 bytes)`
204 -s Warn about unoptimized long branches and applied optimisations.
205 -u Force referenced and undefined symbols global.
206 -v Verbose mode (print running dialogue).
207 -x Turn on debugging mode.
208 -yn Set listing page size to n lines.
209 -4 Use C style operator precedence.
210 file\ *[s]* Assemble the specified file.
211 =================== ===========
213 The switches are described below. A summary of all the switches is given in
217 The **-d** switch permits symbols to be defined on the command line. The name
218 of the symbol to be defined immediately follows the switch (no spaces). The
219 symbol name may optionally be followed by an equals sign (=) and a decimal
220 number. If no value is specified the symbol's value is zero. The symbol at-
221 tributes are "defined, not referenced, and absolute". This switch is most useful
222 for enabling conditionally-assembled debugging code on the command line; for
227 -dDEBUG -dLoopCount=999 -dDebugLevel=55
230 The -e switch causes RMAC to send error messages to a file, instead of the
231 console. If a filename immediately follows the switch character, error messages
232 are written to the specified file. If no filename is specified, a file is created with
233 the default extension "**.err**" and with the root name taken from the first input
234 file name (e.g. error messages are written to "**file.err**" if "**file**" or "**file.s**" is
235 the first input file name). If no errors are encountered, then no error listing
236 file is created. Beware! If an assembly produces no errors, any error file from
237 a previous assembly is not removed.
240 The **-g** switch causes RMAC to generate source-level debug symbols using the
241 stabs format. When linked with a compatible linker such as RLN, these symbols
242 can be used by source-level debuggers such as rdbjag, wdb, or gdb to step
243 through assembly code line-by-line with all the additional context of labels,
244 macros, constants, register equates, etc. available in the original assembly
245 listings rather than relying on the simple disassembly or raw machine code
246 available when stepping through instruction-by-instruction. This option only
247 works with the BSD COFF object file format, as the others do not use the
248 a.out-style symbol tables required by stabs, and RMAC does not currently
249 support placing stabs debug symbols in their own dedicated section in ELF
253 The **-i** switch allows automatic directory searching for include files. A list of
254 semi-colon seperated directory search paths may be mentioned immediately
255 following the switch (with no spaces anywhere). For example:
259 -im:;c:include;c:include\sys
261 will cause the assembler to search the current directory of device **M**, and the
262 directories include and include\sys on drive **C**. If *-i* is not specified, and the
263 enviroment variable "**RMACPATH**" exists, its value is used in the same manner.
264 For example, users of the Mark Williams shell could put the following line in
265 their profile script to achieve the same result as the **-i** example above:
269 setenv RMACPATH="m:;c:include;c:include\sys"
271 The -l switch causes RMAC to generate an assembly listing file. If a file-
272 name immediately follows the switch character, the listing is written to the
273 specified file. If no filename is specified, then a listing file is created with the
274 default extension "**.prn**" and with the root name taken from the first input file
275 name (e.g. the listing is written to "**file.prn**" if "**file**" or "**file.s**" is the first
278 The -o switch causes RMAC to write object code on the specified file. No
279 default extension is applied to the filename. For historical reasons the filename
280 can also be seperated from the switch with a space (e.g. "**-o file**").
285 The **-p** and **-ps** switches cause RMAC to produce an Atari ST executable
286 file with the default extension of "**.prg**". If there are any external references
287 at the end of the assembly, an error message is emitted and no executable file
288 is generated. The **-p** switch does not write symbols to the executable file. The
289 **-ps** switch includes symbols (Alcyon format) in the executable file.
291 The **-q** switch is aimed primarily at users of floppy-disk-only systems. It causes
292 RMAC to install itself in memory, like a RAMdisk. Then the program
293 **m.prg** (which is very short - less than a sector) can be used instead of
294 **mac.prg**, which can take ten or twelve seconds to load. (**NOTE** not available
295 for now, might be re-implemented in the future).
297 The **-s** switch causes RMAC to generate a list of unoptimized forward
298 branches as warning messages. This is used to point out branches that could
299 have been short (e.g. "bra" could be "bra.s").
301 The **-u** switch takes effect at the end of the assembly. It forces all referenced
302 and undefined symbols to be global, exactly as if they had been made global
303 with a **.extern** or **.globl** directive. This can be used if you have a lot of
304 external symbols, and you don't feel like declaring them all external.
306 The **-v** switch turns on a "verbose" mode in which RMAC prints out (for
307 example) the names of the files it is currently processing. Verbose mode is
308 automatically entered when RMAC prompts for input with a star.
310 The **-y** switch, followed immediately by a decimal number (with no intervening
311 space), sets the number of lines in a page. RMAC will produce *N* lines
312 before emitting a form-feed. If *N* is missing or less than 10 an error message is
315 Use C style order of precedence in expressions. See `Order of Evaluation`_ for more
321 Let's assemble and link some example programs. These programs are included
322 on the distribution disk in the "**EXAMPLES**" directory - you should copy them to
323 your work area before continuing. In the following examples we adopt the conven-
324 tions that the shell prompt is a percent sign (%) and that your input (the stuff you
325 type) is presented in **bold face**.
327 If you have been reading carefully, you know that RMAC can generate
328 an executable file without linking. This is useful for making small, stand alone
329 programs that don't require externals or library routines. For example, the following
337 could be replaced by the single command:
343 since you don't need the linker for stand-alone object files.
345 Successive source files named in the command line are are concatenated, as in
346 this example, which assembles three files into a single executable, as if they were
351 % rmac -p bugs shift images
353 Of course you can get the same effect by using the **.include** directive, but sometimes
354 it is convenient to do the concatenation from the command line.
356 Here we have an unbelievably complex command line:
360 % rmac -lzorf -y95 -o tmp -ehack -Ddebug=123 -ps example
362 This produces a listing on the file called "**zorf.prn**" with 95 lines per page, writes
363 the executable code (with symbols) to a file called "**tmp.prg**", writes an error listing
364 to the file "**hack.err**", specifies an include-file path that includes the current
365 directory on the drive "**M:**," defines the symbol "**debug**" to have the value 123, and
366 assembles the file "**example.s**". (Take a deep breath - you got all that?)
368 One last thing. If there are any assembly errors, RMAC will terminate
369 with an exit code of 1. If the assembly succeeds (no errors, although there may be
370 warnings) the exit code will be 0. This is primarily for use with "make" utilities.
372 Things You Should Be Aware Of
373 '''''''''''''''''''''''''''''
374 RMAC is a one pass assembler. This means that it gets all of its work done by
375 reading each source file exactly once and then "back-patching" to fix up forward
376 references. This one-pass nature is usually transparent to the programmer, with
377 the following important exceptions:
379 * In listings, the object code for forward references is not shown. Instead, lower-
380 case "xx"s are displayed for each undefined byte, as in the following example:
384 60xx 1: bra.s.2 ;forward branch
385 xxxxxxxx dc.l .2 ;forward reference
386 60FE .2: bra.s.2 ;backward reference
388 * Forward branches (including **BSR**\s) are never optimized to their short forms.
389 To get a short forward branch it is necessary to explicitly use the ".s" suffix in
391 * Error messages may appear at the end of the assembly, referring to earlier source
392 lines that contained undefined symbols.
393 * All object code generated must fit in memory. Running out of memory is a
394 fatal error that you must deal with by splitting up your source files, re-sizing
395 or eliminating memory-using programs such as ramdisks and desk accessories,
400 RMAC does not optimize forward branches for you, but it will tell you about
401 them if you use the -s (short branch) option:
406 "example.s", line 20: warning: unoptimized short branch
408 With the -e option you can redirect the error output to a file, and determine by
409 hand (or editor macros) which forward branches are safe to explicitly declare short.
411 `Notes for migrating from other 68000 assemblers`_
412 ''''''''''''''''''''''''''''''''''''''''''''''''''
413 RMAC is not entirely compatible with the other popular assemblers
414 like Devpac or vasm. This section
415 outlines the major differences. In practice, we have found that very few changes are
416 necessary to make other assemblers' source code assemble.
418 * A semicolon (;) must be used to introduce a comment,
419 except that a star (*)
420 may be used in the first column. AS68 treated anything following the operand
421 field, preceeded by whitespace, as a comment. (RMAC treats a star that
422 is not in column 1 as a multiplication operator).
423 * Labels require colons (even labels that begin in column 1).
425 * Conditional assembly directives are called **if**, **else** and **endif**.
426 Devpac and vasm call these
427 **ifne**, **ifeq** (etc.), and **endc**.
428 * The tilde (~) character is an operator, and back-quote (`) is an illegal character.
429 AS68 permitted the tilde and back-quote characters in symbols.
430 * There are no equivalents to org or section directives apart from .text, .data, .bss.
431 The **.xdef** and **.xref** directives are not implemented,
432 but **.globl** makes these unnecessary anyway.
434 * The location counter cannot be manipulated with a statement of the form:
440 Exceptions to this rule are when outputting a binary using the **-fr** switch,
441 6502 mode, and Jaguar GPU/DSP.
442 * Back-slashes in strings are "electric" characters that are used to escape C-like
443 character codes. Watch out for GEMDOS path names in ASCII constants -
444 you will have to convert them to double-backslashes.
445 * Expression evaluation is done left-to-right without operator precedence. Use parentheses to
446 force the expression evaluation as you wish. Alternatively, use the **-4** switch to switch
447 to C style precedence. For more information refer to `Order of Evaluation`_.
448 * Mark your segments across files.
449 Branching to a code segment that could be identified as BSS will cause a "Error: cannot initialize non-storage (BSS) section"
450 * In 68020+ mode **Zan** and **Zri** (register suppression) is not supported.
451 * rs.b/rs.w/rs.l/rscount/rsreset can be simulated in rmac using **.abs**.
452 For example the following source:
462 size_so_far equ rscount
474 size_so_far equ ^^abscount
475 * A rare case: if your macro contains something like:
485 then by the assembler's design this will fail as the parameters are automatically converted to hex. Changing the code like this works:
497 For those using editors other than the "Emacs" style ones (Micro-Emacs, Mince,
498 etc.) this section documents the source file format that RMAC expects.
500 * Files must contain characters with ASCII values less than 128; it is not per-
501 missable to have characters with their high bits set unless those characters are
502 contained in strings (i.e. between single or double quotes) or in comments.
504 * Lines of text are terminated with carriage-return/line-feed, linefeed alone, or
505 carriage-return alone.
507 * The file is assumed to end with the last terminated line. If there is text beyond
508 the last line terminator (e.g. control-Z) it is ignored.
515 A statement may contain up to four fields which are identified by order of ap-
516 pearance and terminating characters. The general form of an assembler statement
521 label: operator operand(s) ; comment
523 The label and comment fields are optional. An operand field may not appear
524 without an operator field. Operands are seperated with commas. Blank lines are
525 legal. If the first character on a line is an asterisk (*) or semicolon (;) then the
526 entire line is a comment. A semicolon anywhere on the line (except in a string)
527 begins a comment field which extends to the end of the line.
529 The label, if it appears, must be terminated with a single or double colon. If
530 it is terminated with a double colon it is automatically declared global. It is illegal
531 to declare a confined symbol global (see: `Symbols and Scope`_).
533 As an addition, the exclamation mark character (**!**) can be placed at the very first
534 character of a line to disbale all optimisations for that specific line, i.e.
538 !label: operator operand(s) ; comment
542 A statement may also take one of these special forms:
544 *symbol* **equ** *expression*
546 *symbol* **=** *expression*
548 *symbol* **==** *expression*
550 *symbol* **set** *expression*
552 *symbol* **reg** *register list*
554 The first two forms are identical; they equate the symbol to the value of an
555 expression, which must be defined (no forward references). The third form, double-
556 equals (==), is just like an equate except that it also makes the symbol global. (As
557 with labels, it is illegal to make a confined equate global.) The fourth form allows
558 a symbol to be set to a value any number of times, like a variable. The last form
559 equates the symbol to a 16-bit register mask specified by a register list. It is possible
560 to equate confined symbols (see: `Symbols and Scope`_). For example:
564 cr equ 13 carriage-return
566 DEBUG == 1 global debug flag
568 count set count + 1 increment variable
569 .rags reg d3-d7/a3-a6 register list
570 .cr 13 confined equate
574 Symbols may start with an uppercase or lowercase letter (A-Z a-z), an underscore
575 (**_**), a question mark (**?**) or a period (**.**). Each remaining character may be an
576 upper or lowercase letter, a digit (**0-9**), an underscore, a dollar sign (**$**), or a question
577 mark. (Periods can only begin a symbol, they cannot appear as a symbol
578 continuation character). Symbols are terminated with a character that is not a
579 symbol continuation character (e.g. a period or comma, whitespace, etc.). Case is
580 significant for user-defined symbols, but not for 68000 mnemonics, assembler direc-
581 tives and register names. Symbols are limited to 100 characters. When symbols
582 are written to the object file they are silently truncated to eight (or sixteen) char-
583 acters (depending on the object file format) with no check for (or warnings about)
586 For example, all of the following symbols are legal and unique:
590 reallyLongSymbolName .reallyLongConfinedSymbolName
591 a10 ret move dc frog aa6 a9 ????
592 .a1 .ret .move .dc .frog .a9 .9 ????
593 .0 .00 .000 .1 .11. .111 . ._
594 _frog ?zippo? sys$syetem atari Atari ATARI aTaRi
596 while all of the following symbols are illegal:
600 12days dc.10 dc.z 'quote .right.here
601 @work hi.there $money$ ~tilde
604 Symbols beginning with a period (**.**) are *confined*; their scope is between two
605 normal (unconfined) labels. Confined symbols may be labels or equates. It is illegal
606 to make a confined symbol global (with the ".globl" directive, a double colon, or a
607 double equals). Only unconfined labels delimit a confined symbol's scope; equates
608 (of any kind) do not count. For example, all symbols are unique and have unique
609 values in the following:
620 .loop: move.w -1,(a0)+
624 Confined symbols are useful since the programmer has to be much less inventive
625 about finding small, unique names that also have meaning.
627 It is legal to define symbols that have the same names as processor mnemonics
628 (such as "**move**" or "**rts**") or assembler directives (such as "**.even**"). Indeed, one
629 should be careful to avoid typographical errors, such as this classic (in 6502 mode):
637 which equates a confined symbol to a hexadecimal value, rather than setting the
638 location counter, which the .org directive does (without the equals sign).
642 The following names, in all combinations of uppercase and lowercase, are keywords
643 and may not be used as symbols (e.g. labels, equates, or the names of macros):
651 d0 d1 d2 d3 d4 d5 d6 d7
652 a0 a1 a2 a3 a4 a5 a6 a7
654 r0 r1 r2 r3 r4 r5 r6 r7
655 r8 r9 r10 r11 r12 rl3 r14 r15
659 x x0 x1 x2 y y0 y1 y2
660 a a0 a1 a2 b b0 b1 b2 ab ba
661 mr omr la lc ssh ssl ss
662 n0 n1 n2 n3 n4 n5 n6 n7
663 m0 m1 m2 m3 m4 m5 m6 m7
664 r0 r1 r2 r3 r4 r5 r6 r7
669 Numbers may be decimal, hexadecimal, octal, binary or concatenated ASCII. The
670 default radix is decimal, and it may not be changed. Decimal numbers are specified
671 with a string of digits (**0-9**). Hexadecimal numbers are specified with a leading
672 dollar sign (**$**) followed by a string of digits and uppercase or lowercase letters (**A-F
673 a-f**). Octal numbers are specified with a leading at-sign (**@**) followed by a string
674 of octal digits (**0-7**). Binary numbers are specified with a leading percent sign
675 (**%**) followed by a string of binary digits (**0-1**). Concatenated ASCII constants are
676 specified by enclosing from one to four characters in single or double quotes. For
688 Negative numbers Are specified with a unary minus (**-**). For example:
697 Strings are contained between double (") or single ( ') quote marks. Strings may
698 contain non-printable characters by specifying "backslash" escapes, similar to the
699 ones used in the C programming language. RMAC will generate a warning if a
700 backslash is followed by a character not appearing below:
705 \n $0a line-feed (newline)
708 \r $0c1 carriage-return
714 It is possible for strings (but not symbols) to contain characters with their high
715 bits set (i.e. character codes 128...255).
717 You should be aware that backslash characters are popular in GEMDOS path
718 names, and that you may have to escape backslash characters in your existing source
719 code. For example, to get the file "'c:\\auto\\ahdi.s'" you would specify the string
720 "`c:\\\\auto\\\\ahdi.s`".
724 Register lists are special forms used with the **movem** mnemonic and the **.reg**
725 directive. They are 16-bit values, with bits 0 through 15 corresponding to registers
726 **D0** through **A7**. A register list consists of a series of register names or register
727 ranges seperated by slashes. A register range consists of two register names, Rm
728 and Rn,m<n, seperated by a dash. For example:
736 d0/d1/a0-a3/d7/a6-a7 $CF83
740 Register lists and register equates may be used in conjunction with the movem
741 mnemonic, as in this example:
745 temps reg d0-d2/a0-a2 ; temp registers
746 keeps reg d3-d7/d3-a6 ; registers to preserve
747 allregs reg d0-d7/a0-a7 ; all registers
748 movem.l #temps,-(sp) ; these two lines ...
749 movem.l d0-d2/a0-a2,-(sp) ; are identical
750 movem.l #keeps,-(sp) ; save "keep" registers
751 movem.l (sp)+,#keeps ; restore "keep" registers
756 `Order of Evaluation`_
757 ''''''''''''''''''''''
758 All values are computed with 32-bit 2's complement arithmetic. For boolean operations
759 (such as if or **assert**) zero is considered false, and non-zero is considered
762 **Expressions are evaluated strictly left-to-right, with no
763 regard for operator precedence.**
765 Thus the expression "1+2*3" evaluates to 9, not 7. However, precedence may be
766 forced with parenthesis (**()**) or square-brackets (**[]**).
768 All the above behavior is the default. However if the command line switch **-4**
769 is used, then C style of operator precedence is enforced. The following list
770 shows the order of precedence in this mode, from lowest to highest:
778 * relational = < <= >= > !=
788 Expressions belong to one of three classes: undefined, absolute or relocatable. An
789 expression is undefined if it involves an undefined symbol (e.g. an undeclared sym-
790 bol, or a forward reference). An expression is absolute if its value will not change
791 when the program is relocated (for instance, the number 0, all labels declared in
792 an abs section, and all Atari ST hardware register locations are absolute values).
793 An expression is relocatable if it involves exactly one symbol that is contained in a
794 text, data or BSS section.
796 Only absolute values may be used with operators other than addition (+) or
797 subtraction (-). It is illegal, for instance, to multiply or divide by a relocatable or
798 undefined value. Subtracting a relocatable value from another relocatable value in
799 the same section results in an absolute value (the distance between them, positive
800 or negative). Adding (or subtracting) an absolute value to or from a relocatable
801 value yeilds a relocatable value (an offset from the relocatable address).
803 It is important to realize that relocatable values belong to the sections they
804 are defined in (e.g. text, data or BSS), and it is not permissible to mix and match
805 sections. For example, in this code:
809 linel: dc.l line2, line1+8
810 line2: dc.l line1, line2-8
811 line3: dc.l line2-line1, 8
812 error: dc.l line1+line2, line2 >> 1, line3/4
814 Line 1 deposits two longwords that point to line 2. Line 2 deposits two longwords
815 that point to line 1. Line 3 deposits two longwords that have the absolute value
816 eight. The fourth line will result in an assembly error, since the expressions (re-
817 spectively) attempt to add two relocatable values, shift a relocatable value right by
818 one, and divide a relocatable value by four.
820 The pseudo-symbol "*****" (star) has the value that the current section's location
821 counter had at the beginning of the current source line. For example, these two
822 statements deposit three pointers to the label "**bar**":
829 Similarly, the pseudo-symbol "**$**" has the value that the current section's location
830 counter has, and it is kept up to date as the assembler deposits information
831 "across" a line of source code. For example, these two statements deposit four
832 pointers to the label "zip":
842 ================================ ==========================================
844 ================================ ==========================================
845 **-** Unary minus (2's complement).
846 **!** Logical (boolean) NOT.
847 **~** Tilde: bitwise not (l's complement).
848 **^^defined** *symbol* True if symbol has a value.
849 **^^referenced** *symbol* True if symbol has been referenced.
850 **^^streq** *string1*, *string2* True if the strings are equal.
851 **^^macdef** *macroName* True if the macro is defined.
852 **^^abscount** Returns the size of current .abs section
853 **^^filesize** *string_filename* Returns the file size of supplied filename
854 ================================ ==========================================
856 * The boolean operators generate the value 1 if the expression is true, and 0 if it is not.
858 * A symbol is referenced if it is involved in an expression.
860 any combination of attributes: undefined and unreferenced, defined and unref-
861 erenced (i.e. declared but never used), undefined and referenced (in the case
862 of a forward or external reference), or defined and referenced.
869 =========== ==============================================
871 =========== ==============================================
872 \ + - * / The usual arithmetic operators.
873 % Modulo. Do *not* attempt to modulo by 0 or 1.
874 & | ^ Bit-wise **AND**, **OR** and **Exclusive-OR**.
875 << >> Bit-wise shift left and shift right.
876 < <= >= > Boolean magnitude comparisons.
878 <> != Boolean inequality.
879 =========== ==============================================
881 * All binary operators have the same precedence:
882 expressions are evaluated strictly left to right,
883 with the exception of the **-4** switch. For more information
884 refer to `Order of Evaluation`_.
886 * Division or modulo by zero yields an assembly error.
888 * The "<>" and "!=" operators are synonyms.
890 * Note that the modulo operator (%) is also used to introduce binary constants
891 (see: `Constants`_). A percent sign should be followed by at least one space if
892 it is meant to be a modulo operator, and is followed by a '0' or '1'.
897 ============ =========================================
898 Special Form Description
899 ============ =========================================
900 **^^date** The current system date (Gemdos format).
901 **^^time** The current system time (Gemdos format).
902 ============ =========================================
904 * The "**^^date**" special form expands to the current system date, in Gemdos
905 format. The format is a 16-bit word with bits 0 ...4 indicating the day of the
906 month (1...31), bits 5...8 indicating the month (1...12), and bits 9...15
907 indicating the year since 1980, in the range 0...119.
909 * The "**^^time**" special form expands to the current system time, in Gemdos
910 format. The format is a 16-bit word with bits 0...4 indicating the current
911 second divided by 2, bits 5...10 indicating the current minute 0...59. and
912 bits 11...15 indicating the current hour 0...23.
914 `Example Expressions`_
915 ''''''''''''''''''''''
919 line address contents source code
920 ---- ------- -------- -------------------------------
921 1 00000000 4480 lab1: neg.l d0
922 2 00000002 427900000000 lab2: clr.w lab1
923 3 =00000064 equ1 = 100
924 4 =00000096 equ2 = equ1 + 50
925 5 00000008 00000064 dc.l lab1 + equ1
926 6 0000000C 7FFFFFE6 dc.l (equl + ~equ2) >> 1
927 7 00000010 0001 dc.w ^^defined equl
928 8 00000012 0000 dc.w ^^referenced lab2
929 9 00000014 00000002 dc.l lab2
930 10 00000018 0001 dc.w ^^referenced lab2
931 11 0000001A 0001 dc.w lab1 = (lab2 - 6)
933 Lines 1 through four here are used to set up the rest of the example. Line 5 deposits
934 a relocatable pointer to the location 100 bytes beyond the label "**lab1**". Line 6 is
935 a nonsensical expression that uses the and right-shift operators. Line 7 deposits
936 a word of 1 because the symbol "**equ1**" is defined (in line 3).
938 Line 8 deposits a word of 0 because the symbol "**lab2**", defined in line 2, has
939 not been referenced. But the expression in line 9 references the symbol "**lab2**", so
940 line 10 (which is a copy of line-8) deposits a word of 1. Finally, line 11 deposits a
941 word of 1 because the Boolean equality operator evaluates to true.
943 The operators "**^^defined**" and "**^^referenced**" are particularly useful in
944 conditional assembly. For instance, it is possible to automatically include debugging
945 code if the debugging code is referenced, as in:
949 lea string,a0 ; AO -> message
950 jsr debug ; print a message
952 string: dc.b "Help me, Spock!",0 ; (the message)
956 .iif ^^referenced debug, .include "debug.s"
958 The **jsr** statement references the symbol debug. Near the end of the source file, the
959 "**.iif**" statement includes the file "**debug.s**" if the symbol debug was referenced.
961 In production code, presumably all references to the debug symbol will be removed,
962 and the debug source file will not be included. (We could have as easily made the
963 symbol **debug** external, instead of including another source file).
969 Assembler directives may be any mix of upper- or lowercase. The leading periods
970 are optional, though they are shown here and their use is encouraged. Directives
971 may be preceeded by a label; the label is defined before the directive is executed.
972 Some directives accept size suffixes (**.b**, **.s**, **.w**, **.1**, **.d**, **.x**, **.p**, or **.q**);
973 the default is word (**.w**) if no size is specified. The **.s** suffix is identical to **.b**,
974 with the exception of being used in a **dc** statement. In that case the **.s**
975 refers to single precision floating point numbers.
976 Directives relating to the 6502 are described in the chapter on `6502 Support`_.
982 If the location counter for the current section is odd, make it even by adding
983 one to it. In text and data sections a zero byte is deposited if necessary.
987 Align the program counter to the next integral long boundary (4 bytes).
988 Note that GPU/DSP code sections are not contained in their own
989 segments and are actually part of the TEXT or DATA segments.
990 Therefore, to align GPU/DSP code, align the current section before and
991 after the GPU/DSP code.
994 This directive is similar to the standard ‘C’ library printf() function
995 and is used to print user messages from the assembly process. You can
996 print any string or valid expression. Several format flags that can be used
997 to format your output are also supported.
1013 .print “Mask: $”,/x/w MASK
1014 .print “Value: “,/d/l VALUE
1018 Align the program counter to the next integral phrase boundary (8 bytes).
1019 Note that GPU/DSP code sections are not contained in their own
1020 segments and are actually part of the TEXT or DATA segments.
1021 Therefore, to align GPU/DSP code, align the current section before and
1022 after the GPU/DSP code.
1026 Align the program counter to the next integral double phrase boundary (16
1027 bytes). Note that GPU/DSP code sections are not contained in their own
1028 segments and are actually part of the TEXT or DATA segments.
1029 Therefore, to align GPU/DSP code, align the current section before and
1030 after the GPU/DSP code.
1034 Align the program counter to the next integral quad phrase boundary (32
1035 bytes). Note that GPU/DSP code sections are not contained in their own
1036 segments and are actually part of the TEXT or DATA segments.
1037 Therefore, to align GPU/DSP code, align the current section before and
1038 after the GPU/DSP code.
1040 **.assert** *expression* [,\ *expression*...]
1042 Assert that the conditions are true (non-zero). If any of the comma-seperated
1043 expressions evaluates to zero an assembler warning is issued. For example:
1047 .assert *-start = $76
1048 .assert stacksize >= $400
1056 Switch to the BSS, data or text segments. Instructions and data may not
1057 be assembled into the BSS-segment, but symbols may be defined and storage
1058 may be reserved with the **.ds** directive. Each assembly starts out in the text
1067 Enable different flavours of the MC68000 family of CPUs. Bear in mind that not all
1068 instructions and addressing modes are available in all CPUs so the correct CPU
1069 should be selected at all times. Notice that it is possible to switch CPUs
1075 Enable FPU support. Note that *.68882* is on by default when selecting *.68030*.
1079 Switch to Motorola DSP56001 mode.
1081 **.org** *location* [*X:*/*Y:*/*P:*/*L:*]
1083 This directive sets the value of the location counter (or **pc**) to location, an
1084 expression that must be defined and absolute. It is legal to use the directive in
1085 the following modes: 6502, Tom, Jerry, OP, 56001 and 680x0 (only with -fr switch).
1086 Especially for the 56001 mode the *location* field **must** be prefixed with the
1087 intended section (*X:*, *Y:*, *P:* or *L:*).
1094 These directives control the optimisations that rmac applies to the source
1095 automatically. Each directive is applied immediately from the line encountered
1096 onwards. So it is possible to turn specific optimisations on and off globally
1097 (when placed at the start of the first file) or locally (by turning desired
1098 optimisations on and off at certain parts of the source). For a list of the
1099 optimisations (*n*) available please consult the table in section `The Command Line`_.
1101 **all**, as expected, turns all available optimisations on or off. An exception to this
1102 is *o10*/*op* as this is not an optimisation that should be turned on unless the user
1103 absolutely needs it.
1105 Lastly, as a "creature comfort" feature, if the first column of any line is prefixed
1106 with an exclamation mark (*!*) then for that line all optimisations are turned off.
1108 **.abs** [*location*]
1110 Start an absolute section, beginning with the specified location (or zero, if
1111 no location is specified). An absolute section is much like BSS, except that
1112 locations declared with .ds are based absolute. This directive is useful for
1113 declaring structures or hardware locations.
1114 For example, the following equates:
1124 could be as easily defined as:
1135 Another interesting example worth mentioning is the emulation of "C"'s "union" keyword
1136 using *.abs*. For example, the following "C" code:
1146 union { int spf_em_colour; int spf_emx_colour; };
1147 union { int spf_em_psmask[16]; int spf_emx_colouropt; };
1150 can be expressed as:
1155 *-------------------------------------------------------*
1156 spf_w: ds.w 1 ;<- common
1161 *-------------------------------------------------------*
1163 spf_em_colour: ds.l 1 ;<- union #1
1164 spf_em_psmask: ds.l 16
1165 *-------------------------------------------------------*
1169 spf_emx_colour: ds.l 1 ;<- union #2
1170 spf_emx_colouropt: ds.l 1
1171 spf_emx_psmask: ds.l 16
1172 spf_emx_psmaskopt: ds.l 16
1175 ;*-------------------------------------------------------*
1177 move #spf_em_colour,d0
1178 move #spf_emx_colour,d0
1180 In this example, *spf_em_colour* and *spf_emx_colour* will have the same value.
1182 **.comm** *symbol*, *expression*
1184 Specifies a label and the size of a common region. The label is made global,
1185 thus confined symbols cannot be made common. The linker groups all common
1186 regions of the same name; the largest size determines the real size of the
1187 common region when the file is linked.
1189 **.ccdef** *expression*
1191 Allows you to define names for the condition codes used by the JUMP
1192 and JR instructions for GPU and DSP code. For example:
1198 jump Always,(r3) ; 'Always' is actually 0
1200 **.ccundef** *regname*
1202 Undefines a register name (regname) previously assigned using the
1203 .CCDEF directive. This is only implemented in GPU and DSP code
1206 **.dc.i** *expression*
1208 This directive generates long data values and is similar to the DC.L
1209 directive, except the high and low words are swapped. This is provided
1210 for use with the GPU/DSP MOVEI instruction.
1212 **.dc**\ [.\ *size*] *expression* [, *expression*...]
1214 Deposit initialized storage in the current section. If the specified size is word
1215 or long, the assembler will execute a .even before depositing data. If the size
1216 is .b, then strings that are not part of arithmetic expressions are deposited
1217 byte-by-byte. If no size is specified, the default is .w. This directive cannot be
1218 used in the BSS section.
1220 **.dcb**\ [.\ *size*] *expression1*, *expression2*
1222 Generate an initialized block of *expression1* bytes, words or longwords of the
1223 value *expression2*. If the specified size is word or long, the assembler will
1224 execute .even before generating data. If no size is specified, the default is **.w**.
1225 This directive cannot be used in the BSS section.
1227 **.ds**\ [.\ *size*] *expression*
1229 Reserve space in the current segment for the appropriate number of bytes,
1230 words or longwords. If no size is specified, the default size is .w. If the size
1231 is word or long, the assembler will execute .even before reserving space.
1235 Switch to Jaguar DSP assembly mode. This directive must be used
1236 within the TEXT or DATA segments.
1238 **.init**\ [.\ *size*] [#\ *expression*,]\ *expression*\ [.\ *size*] [,...]
1240 Generalized initialization directive. The size specified on the directive becomes
1241 the default size for the rest of the line. (The "default" default size is **.w**.) A
1242 comma-seperated list of expressions follows the directive; an expression may be
1243 followed by a size to override the default size. An expression may be preceeded
1244 by a sharp sign, an expression and a comma, which specifies a repeat count to
1245 be applied to the next expression. For example:
1249 .init.l -1, 0.w, #16,'z'.b, #3,0, 11.b
1251 will deposit a longword of -1, a word of zero, sixteen bytes of lower-case 'z',
1252 three longwords of zero, and a byte of 11.
1254 No auto-alignment is performed within the line, but a **.even** is done once
1255 (before the first value is deposited) if the default size is word or long.
1257 **.cargs** [#\ *expression*,] *symbol*\ [.\ *size*] [, *symbol*\ [.\ *size*].. .]
1259 Compute stack offsets to C (and other language) arguments. Each symbol is
1260 assigned an absolute value (like equ) which starts at expression and increases
1261 by the size of each symbol, for each symbol. If the expression is not supplied,
1262 the default starting value is 4. For example:
1266 .cargs #8, .fileliams.1, .openMode, .butPointer.l
1268 could be used to declare offsets from A6 to a pointer to a filename, a word
1269 containing an open mode, and a pointer to a buffer. (Note that the symbols
1270 used here are confined). Another example, a C-style "string-length" function,
1271 could be written as:
1275 _strlen:: .cargs .string ; declare arg
1276 move.l .string(sp),a0 ; a0 -> string
1277 moveq #-1,d0 ; initial size = -1
1278 .1: addq.1 #1,d0 ; bump size
1279 tst.b (a0)+ ; at end of string?
1280 bne .1 ; (no -- try again)
1281 rts ; return string length
1283 **.error** ["*string*"]
1285 Aborts the build, optionally printing a user defined string. Can be useful
1286 inside conditional assembly blocks in order to catch errors. For example:
1290 .if ^^defined JAGUAR
1291 .error "TOS cannot be built on Jaguar, don't be silly"
1296 End the assembly. In an include file, end the include file and resume assembling
1297 the superior file. This statement is not required, nor are warning messages
1298 generated if it is missing at the end of a file. This directive may be used inside
1299 conditional assembly, macros or **.rept** blocks.
1301 **.equr** *expression*
1303 Allows you to name a register. For example:
1310 add ClipW,r0 ; ClipW actually is r19
1312 **.if** *expression*
1318 Start a block of conditional assembly. If the expression is true (non-zero) then
1319 assemble the statements between the .if and the matching **.endif** or **.else**.
1320 If the expression is false, ignore the statements unless a matching .else is
1321 encountered. Conditional assembly may be nested to any depth.
1323 It is possible to exit a conditional assembly block early from within an include
1324 file (with **end**) or a macro (with **endm**).
1326 **.iif** *expression*, *statement*
1328 Immediate version of **.if**. If the expression is true (non-zero) then the state-
1329 ment, which may be an instruction, a directive or a macro, is executed. If
1330 the expression is false, the statement is ignored. No **.endif** is required. For
1335 .iif age < 21, canDrink = 0
1336 .iif weight > 500, dangerFlag = 1
1337 .iif !(^^defined DEBUG), .include dbsrc
1339 **.macro** *name* [*formal*, *formal*,...]
1345 Define a macro called name with the specified formal arguments. The macro
1346 definition is terminated with a **.endm** statement. A macro may be exited early
1347 with the .exitm directive. See the chapter on `Macros`_ for more information.
1349 **.undefmac** *macroName* [, *macroName*...]
1351 Remove the macro-definition for the specified macro names. If reference is
1352 made to a macro that is not defined, no error message is printed and the name
1355 **.rept** *expression*
1359 The statements between the **.rept** and **.endr** directives will be repeated *expression*
1360 times. If the expression is zero or negative, no statements will be
1361 assembled. No label may appear on a line containing either of these directives.
1363 **.globl** *symbol* [, *symbol*...]
1365 **.extern** *symbol* [, *symbol*...]
1367 Each symbol is made global. None of the symbols may be confined symbols
1368 (those starting with a period). If the symbol is defined in the assembly, the
1369 symbol is exported in the object file. If the symbol is undefined at the end
1370 of the assembly, and it was referenced (i.e. used in an expression), then the
1371 symbol value is imported as an external reference that must be resolved by the
1372 linker. The **.extern** directive is merely a synonym for **.globl**.
1374 **.include** "*file*"
1376 Include a file. If the filename is not enclosed in quotes, then a default extension
1377 of "**.s**" is applied to it. If the filename is quoted, then the name is not changed
1380 Note: If the filename is not a valid symbol, then the assembler will generate an
1381 error message. You should enclose filenames such as "**atari.s**" in quotes,
1382 because such names are not symbols.
1384 If the include file cannot be found in the current directory, then the directory
1385 search path, as specified by -i on the commandline, or' by the 'RMACPATH'
1386 enviroment string, is traversed.
1388 **.incbin** "*file*" [, [*size*], [*offset*]]
1390 Include a file as a binary. This can be thought of a series of **dc.b** statements
1391 that match the binary bytes of the included file, inserted at the location of the
1392 directive. The directive is not allowed in a BSS section. Optional parameters
1393 control the amount of bytes to be included and offset from the start of the file.
1394 All the following lines are valid:
1397 .incbin "test.bin" ; Include the whole file
1398 .incbin "test.bin",,$30 ; Skip the first 48 bytes
1399 .incbin "test.bin",$70,$30 ; Include $70 bytes starting at offset $30
1400 .incbin "test.bin",$48 ; Include the file starting at offset 48 till the end
1401 .incbin "test.bin",, ; Include the whole file
1405 Issue a page eject in the listing file.
1407 **.title** "*string*"
1409 **.subttl** [-] "*string*"
1411 Set the title or subtitle on the listing page. The title should be specified on
1412 the the first line of the source program in order to take effect on the first page.
1413 The second and subsequent uses of **.title** will cause page ejects. The second
1414 and subsequent uses of .subttl will cause page ejects unless the subtitle string
1415 is preceeded by a dash (-).
1421 Enable or disable source code listing. These directives increment and decrement
1422 an internal counter, so they may be appropriately nested. They have no effect
1423 if the **-l** switch is not specified on the commandline.
1427 This directive provides unstructured flow of control within a macro definition.
1428 It will transfer control to the line of the macro containing the specified goto
1429 label. A goto label is a symbol preceeded by a colon that appears in the first
1430 column of a source line within a macro definition:
1434 where the label itself can be any valid symbol name, followed immediately by
1435 whitespace and a valid source line (or end of line). The colon **must** appear in
1438 The goto-label is removed from the source line prior to macro expansion -
1439 to all intents and purposes the label is invisible except to the .goto directive
1440 Macro expansion does not take place within the label.
1442 For example, here is a silly way to count from 1 to 10 without using **.rept**:
1450 iif count <= 10, goto loop
1455 Switch to Jaguar GPU assembly mode. This directive must be used
1456 within the TEXT or DATA segments.
1460 No. Just... no. Don't ask about it. Ever.
1462 **.prgflags** *value*
1464 Sets ST executable .PRG field *PRGFLAGS* to *value*. *PRGFLAGS* is a bit field defined as follows:
1466 ============ ====== =======
1467 Definition Bit(s) Meaning
1468 ============ ====== =======
1469 PF_FASTLOAD 0 If set, clear only the BSS area on program load, otherwise clear the entire heap.
1470 PF_TTRAMLOAD 1 If set, the program may be loaded into alternative RAM, otherwise it must be loaded into standard RAM.
1471 PF_TTRAMMEM 2 If set, the program's Malloc() requests may be satisfied from alternative RAM, otherwise they must be satisfied from standard RAM.
1472 -- 3 Currently unused.
1473 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.
1474 -- 6-15 Currently unused.
1475 ============ ====== =======
1477 **.regequ** *expression*
1478 Essentially the same as **.EQUR.** Included for compatibility with the GASM
1482 Essentially the same as **.EQURUNDEF.** Included for compatibility with
1491 All of the standard Motorola 68000 mnemonics and addressing modes are supported;
1492 you should refer to **The Motorola M68000 Programmer's Reference Manual**
1493 for a description of the instruction set and the allowable addressing modes for each
1494 instruction. With one major exception (forward branches) the assembler performs
1495 all the reasonable optimizations of instructions to their short or address register
1498 Register names may be in upper or lower case. The alternate forms ``R0`` through
1499 ``R15`` may be used to specify ``D0`` through ``A7``. All register names are keywords, and
1500 may not be used as labels or symbols. None of the 68010 or 68020 register names
1501 are keywords (but they may become keywords in the future).
1506 ===================================== ===========================================
1507 Assembler Syntax Description
1508 ===================================== ===========================================
1509 *Dn* Data register direct
1510 *An* Address register direct
1511 (*An*) Address register indirect
1512 (*An*)+ Address register indirect postincrement
1513 -(*An*) Address register indirect predecrement
1514 *disp*\ (*An*) Address register indirect with displacement
1515 *bdisp*\ (*An*, *Xi*\ [.\ *size*]) Address register indirect indexed
1516 *abs*.w Absolute short
1517 *abs* Absolute (long or short)
1518 *abs*.l Forced absolute long
1519 *disp*\ (PC) Program counter with displacement
1520 *bdisp*\ (PC, *Xi*\ ) Program counter indexed
1522 ===================================== ===========================================
1524 `68020+ Addressing Modes`_
1525 ''''''''''''''''''''''''''
1527 The following addressing modes are only valid for 68020 and newer CPUs. In these
1528 modes most of the parameters like Base Displacement (**bd**), Outer Displacement
1529 (**od**), Base Register (**An**) and Index Register (**Xn**) can be omitted. RMAC
1530 will detect this and *suppress* the registers in the produced code.
1533 use a special syntax to denote register suppression like **Zan** to suppress the Base
1534 Register and **Rin** to suppress the Index Register. RMAC has no support for this
1535 behaviour nor needs it to suppress registers.
1537 In addition, other assemblers will allow reordering of the parameters (for example
1538 ([*An*,\ *bd*])). This is not allowed in RMAC.
1540 Also noteworthy is that the Index Register can be an address or data register.
1542 To avoid internal confusion the 68040/68060 registers *DC*, *IC* and *BC* are named
1543 *DC40*, *IC40* and *BC40* respectively.
1545 ====================================================== =============================================================
1546 Assembler Syntax Description
1547 ====================================================== =============================================================
1548 *bd*\ (*An*, *Xi*\ [.\ *size*][*\*scale*]) Address register indirect indexed
1549 ([*bd*,\ *An*],\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Register indirect preindexed with outer displacement
1550 ([*bd*,\ *An*,\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Register indirect postindexed with outer displacement
1551 ([*bd*,\ *PC*],\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Program counter indirect preindexed with outer displacement
1552 ([*bd*,\ *PC*,\ *Xn*\[.\ *siz*][*\*scale*],\ *od*) Program counter indirect postindexed with outer displacement
1553 ====================================================== =============================================================
1557 Since RMAC is a one pass assembler, forward branches cannot be automatically
1558 optimized to their short form. Instead, unsized forward branches are assumed to
1559 be long. Backward branches are always optimized to the short form if possible.
1561 A table that lists "extra" branch mnemonics (common synonyms for the Motorola
1562 defined mnemonics) appears below.
1564 `Linker Constraints`_
1565 '''''''''''''''''''''
1566 It is not possible to make an external reference that will fix up a byte. For example:
1571 move.l frog(pc,d0),d1
1573 is illegal (and generates an assembly error) when frog is external, because the
1574 displacement occupies a byte field in the 68000 offset word, which the object file
1579 ============== ========
1580 Alternate name Becomes:
1581 ============== ========
1591 ============== ========
1593 `Optimizations and Translations`_
1594 '''''''''''''''''''''''''''''''''
1595 The assembler provides "creature comforts" when it processes 68000 mnemonics:
1597 * **CLR.x An** will really generate **SUB.x An,An**.
1599 * **ADD**, **SUB** and **CMP** with an address register will really generate **ADDA**,
1600 **SUBA** and **CMPA**.
1602 * The **ADD**, **AND**, **CMP**, **EOR**, **OR** and **SUB** mnemonics with immediate
1603 first operands will generate the "I" forms of their instructions (**ADDI**, etc.) if
1604 the second operand is not register direct.
1606 * All shift instructions with no count value assume a count of one.
1608 * **MOVE.L** is optimized to **MOVEQ** if the immediate operand is defined and
1609 in the range -128...127. However, **ADD** and **SUB** are never translated to
1610 their quick forms; **ADDQ** and **SUBQ** must be explicit.
1612 * All optimisations are controllable using the **.opt** directive. Refer to its
1613 description in section `Directives`_.
1615 * All optimisations are turned off for any source line that has an exclamation mark
1616 (*!*) on their first column.
1618 * Optimisation switch 11 is turned on by default for compatibility with the
1619 Motorola reference 56001 DSP assembler.
1620 All other levels are off by default. (refer to section `The Command Line`_
1621 for a description of all the switches).
1623 * Optimisation warnings are off by default. Invoke RMAC with the *-s* switch to
1624 turn on warnings in console and listing output.
1626 * In GPU/DSP code sections, you can use JUMP (Rx) in place of JUMP T, (Rx) and JR
1627 (Rx) in place of JR T,(Rx).
1629 * RMAC tests all GPU/DSP restrictions and corrects them wherever possible (such as
1630 inserting a NOP instruction when needed).
1632 * The *(Rx+N)* addressing mode for GPU/DSP instructions is optimized to *(Rx)*
1637 `Macro declaration`_
1638 ''''''''''''''''''''
1639 A macro definition is a series of statements of the form:
1642 .macro name [ formal-arg, ...]
1646 statements making up the macro body
1652 The name of the macro may be any valid symbol that is not also a 68000 instruction
1653 or an assembler directive. (The name may begin with a period - macros cannot
1654 be made confined the way labels or equated symbols can be). The formal argument
1655 list is optional; it is specified with a comma-seperated list of valid symbol names.
1656 Note that there is no comma between the name of the macro and the name of the
1657 first formal argument. It is not advised to begin an argument name with a numeric
1660 A macro body begins on the line after the **.macro** directive. All instructions
1661 and directives, except other macro definitions, are legal inside the body.
1663 The macro ends with the **.endm** statement. If a label appears on the line with
1664 this directive, the label is ignored and a warning is generated.
1666 `Parameter Substitution`_
1667 '''''''''''''''''''''''''
1668 Within the body, formal parameters may be expanded with the special forms:
1674 The second form (enclosed in braces) can be used in situations where the characters
1675 following the formal parameter name are valid symbol continuation characters. This
1676 is usually used to force concatentation, as in:
1681 \(godzilla}vs\{reagan}
1683 The formal parameter name is terminated with a character that is not valid in
1684 a symbol (e.g. whitespace or puncuation); optionally, the name may be enclosed in
1685 curly-braces. The names must be symbols appearing on the formal argument list,
1686 or a single decimal digit (``\1`` corresponds to the first argument, ``\2`` to the second,
1687 ``\9`` to the ninth, and ``\0`` to the tenth). It is possible for a macro to have more than
1688 ten formal arguments, but arguments 11 and on must be referenced by name, not
1691 Other special forms are:
1693 ============ ================================================
1694 Special Form Description
1695 ============ ================================================
1696 ``\\`` a single "\",
1697 ``\~`` a unique label of the form "Mn"
1698 ``\#`` the number of arguments actually specified
1699 ``\!`` the "dot-size" specified on the macro invocation
1700 ``\?name`` conditional expansion
1701 ``\?{name}`` conditional expansion
1702 ============ ================================================
1704 The last two forms are identical: if the argument is specified and is non-empty, the
1705 form expands to a "1", otherwise (if the argument is missing or empty) the form
1708 The form "``\!``" expands to the "dot-size" that was specified when the macro
1709 was invoked. This can be used to write macros that behave differently depending
1710 on the size suffix they are given, as in this macro which provides a synonym for the
1715 .macro deposit value
1718 deposit.b 1 ; byte of 1
1719 deposit.w 2 ; word of 2
1720 deposit.l 3 ; longvord of 3
1721 deposit 4 ; word of 4 (no explicit size)
1725 A previously-defined macro is called when its name appears in the operation field of
1726 a statement. Arguments may be specified following the macro name; each argument
1727 is seperated by a comma. Arguments may be empty. Arguments are stored for
1728 substitution in the macro body in the following manner:
1730 * Numbers are converted to hexadecimal.
1732 * All spaces outside strings are removed.
1734 * Keywords (such as register names, dot sizes and "^^" operators) are converted
1737 * Strings are enclosed in double-quote marks (").
1739 For example, a hypothetical call to the macro "``mymacro``", of the form:
1740 ``mymacro A0, , 'Zorch' / 32, "^^DEFINED foo, , , tick tock``
1742 will result in the translations:
1744 ======== ================= =================================================
1745 Argument Expansion Comment
1746 ======== ================= =================================================
1747 ``\1`` ``a0`` "``A0``" converted to lower-case
1749 ``\3`` ``"Zorch"/$20`` "``Zorch``" in double-quotes, 32 in hexadecimal
1750 ``\4`` ``^^defined foo`` "``^^DEFINED``" converted to lower-case
1753 ``\7`` ``ticktock`` spaces removed (note concatenation)
1754 ======== ================= =================================================
1756 The **.exitm** directive will cause an immediate exit from a macro body. Thus
1757 the macro definition:
1762 .iif !\?source, .exitm ; exit if source is empty
1763 move \source,d0 ; otherwise, deposit source
1766 will not generate the move instruction if the argument **"source"** is missing from
1767 the macro invocation.
1769 The **.end**, **.endif** and **.exitm** directives all pop-out of their include levels
1770 appropriately. That is, if a macro performs a **.include** to include a source file, an
1771 executed **.exitm** directive within the include-file will pop out of both the include-file
1774 Macros may be recursive or mutually recursive to any level, subject only to
1775 the availability of memory. When writing recursive macros, take care in the coding
1776 of the termination condition(s). A macro that repeatedly calls itself will cause the
1777 assembler to exhaust its memory and abort the assembly.
1782 The Gemdos macro is used to make file system calls. It has two parameters, a
1783 function number and the number of bytes to clean off the stack after the call. The
1784 macro pushes the function number onto the stack and does the trap to the file
1785 system. After the trap returns, conditional assembly is used to choose an addq or
1786 an **add.w** to remove the arguments that were pushed.
1790 .macro Gemdos trpno, clean
1791 move.w #\trpno,-(sp) ; push trap number
1792 trap #1 ; do GEMDOS trap
1794 addq #\clean,sp ; clean-up up to 8 bytes
1796 add.w #\clean,sp ; clean-up more than 8 bytes
1800 The Fopen macro is supplied two arguments; the address of a filename, and
1801 the open mode. Note that plain move instructions are used, and that the caller of
1802 the macro must supply an appropriate addressing mode (e.g. immediate) for each
1807 .macro Fopen file, mode
1808 movs.w \mode,-(sp) ;push open mode
1809 move.1 \file,-(sp) ;push address of tile name
1810 Gemdos $3d,8 ;do the GEMDOS call
1813 The **String** macro is used to allocate storage for a string, and to place the
1814 string's address somewhere. The first argument should be a string or other expres-
1815 sion acceptable in a dc.b directive. The second argument is optional; it specifies
1816 where the address of the string should be placed. If the second argument is omitted,
1817 the string's address is pushed onto the stack. The string data itself is kept in the
1822 .macro String str,loc
1823 .if \?loc ; if loc is defined
1824 move.l #.\~,\loc ; put the string's address there
1826 pea .\~ ; push the string's address
1828 .data ; put the string data
1829 .\~: dc.b \str,0 ; in the data segment
1830 .text ; and switch back to the text segment
1833 The construction "``.\~``" will expand to a label of the form "``.M``\ *n*" (where *n* is
1834 a unique number for every macro invocation), which is used to tag the location of
1835 the string. The label should be confined because the macro may be used along with
1836 other confined symbols.
1838 Unique symbol generation plays an important part in the art of writing fine
1839 macros. For instance, if we needed three unique symbols, we might write "``.a\~``",
1840 "``.b\~``" and "``.c\~``".
1844 Repeat-blocks provide a simple iteration capability. A repeat block allows a range
1845 of statements to be repeated a specified number of times. For instance, to generate
1846 a table consisting of the numbers 255 through 0 (counting backwards) you could
1851 .count set 255 ; initialize counter
1852 .rept 256 ; repeat 256 times:
1853 dc.b .count ; deposit counter
1854 .count set .count - 1 ; and decrement it
1855 .endr ; (end of repeat block)
1857 Repeat blocks can also be used to duplicate identical pieces of code (which are
1858 common in bitmap-graphics routines). For example:
1862 .rept 16 ; clear 16 words
1863 clr.w (a0)+ ; starting at AO
1866 `Jaguar GPU/DSP Mode`_
1867 ======================
1869 RMAC will generate code for the Atari Jaguar GPU and DSP custom RISC (Reduced
1870 Instruction Set Computer) processors. See the Atari Jaguar Software reference Manual - Tom
1871 & Jerry for a complete listing of Jaguar GPU and DSP assembler mnemonics and addressing
1876 The following condition codes for the GPU/DSP JUMP and JR instructions are built-in:
1880 CC (Carry Clear) = %00100
1881 CS (Carry Set) = %01000
1884 NE (Not Equal) = %00001
1886 HI (Higher) = %00101
1889 `Jaguar Object Processor Mode`_
1890 ===============================
1895 An assembler to generate object lists for the Atari Jaguar's Object processor.
1901 To really utilize the OP properly, it needs an assembler. Otherwise, what
1902 happens is you end up writing an assembler in your code to assemble the OP
1903 list, and that's a real drag--something that *should* be handled by a proper
1908 ''''''''''''''''''''
1910 The OP assembler works similarly to the RISC assembler; to enter the OP
1911 assembler, you put the .objproc directive in your code (N.B.: like the RISC
1912 assembler, it only works in a TEXT or DATA section). From there, you build
1913 the OP list how you want it and go from there. A few caveats: you will want
1914 to put a .org directive at the top of your list, and labels that you want to
1915 be able to address in 68xxx code (for moving from a data section to an
1916 address where it will be executed by the OP, for example) should be created
1920 `What are the opcodes?`_
1921 ''''''''''''''''''''''''
1923 They are **bitmap**, **scbitmap**, **gpuobj**, **branch**, **stop**, **nop**, and **jump**. **nop** and **jump**
1924 are psuedo-ops, they are there as a convenience to the coder.
1927 `What are the proper forms for these opcodes?`_
1928 '''''''''''''''''''''''''''''''''''''''''''''''
1930 They are as follows:
1932 **bitmap** *data addr*, *xloc*, *yloc*, *dwidth*, *iwidth*, *iheight*, *bpp*,
1933 *pallete idx*, *flags*, *firstpix*, *pitch*
1935 **scbitmap** *data addr*, *xloc*, *yloc*, *dwidth*, *iwidth*, *iheight*,
1936 *xscale*, *yscale*, *remainder*, *bpp*, *pallete idx*,
1937 *flags*, *firstpix*, *pitch*
1939 **gpuobj** *line #*, *userdata* (bits 14-63 of this object)
1941 **branch** VC *condition (<, =, >)* *line #*, *link addr*
1943 **branch** OPFLAG, *link addr*
1945 **branch** SECHALF, *link addr*
1951 **jump** *link addr*
1953 Note that the *flags* field in bitmap and scbitmap objects consist of the
1954 following: **REFLECT**, **RMW**, **TRANS**, **RELEASE**. They can be in any order (and
1955 should be separated by whitespace **only**), and you can only put a maximum of
1956 four of them in. Further note that with bitmap and scbitmap objects, all the
1957 parameters after *data addr* are optional--if they are omitted, they will
1958 use defaults (mostly 0, but 1 is the default for pitch). Also, in the
1959 scbitmap object, the *xscale*, *yscale*, and *remainder* fields can be
1960 floating point constants/expressions. *data addr* can refer to any address
1961 defined (even external!) and the linker (rln v1.6.0 or greater) will
1962 properly fix up the address.
1968 Pretty much what you expect. It's beyond the scope of this little note to
1969 explain the Jaguar's Object Processor and how it operates, so you'll have to
1970 seek explanations for how they work elsewhere.
1973 `Why do I want to put a *.org* directive at the top of my list?`_
1974 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
1976 You want to put a *.org* directive at the top of your list because otherwise
1977 the assembler will not know where in memory the object list is supposed
1978 go--then when you move it to its destination, the object link addresses will
1979 all be wrong and it won't work.
1982 `Why would I copy my object list to another memory location?`_
1983 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
1985 Simple: because the OP destroys the list as it uses it to render the screen.
1986 If you don't keep a fresh copy stashed away somewhere to refresh it before
1987 the next frame is rendered, what you see on the screen will not be what you
1988 expect, as the OP has scribbled all over it!
1991 `Does the assembler do anything behind my back?`_
1992 '''''''''''''''''''''''''''''''''''''''''''''''''
1994 Yes, it will emit **NOP** s to ensure that bitmaps and scbitmaps are on proper
1995 memory boundaries, and fixup link addresses as necessary. This is needed
1996 because of a quirk in how the OP works (it ORs constants on the address
1997 lines to get the phrases it needs and if they are not zeroes, it will fail
1998 in bizarre ways). It will also set all *ypos* constants on the correct
1999 half-line (as that's how the OP views them).
2002 `Why can't I define the link addresses for all the objects?`_
2003 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
2005 You really, *really* don't want to do this. Trust me on this one.
2007 `How about an example of an object list?`_
2008 ''''''''''''''''''''''''''''''''''''''''''
2016 objects: ; This is the label you will use to address this in 68K code
2017 .objproc ; Engage the OP assembler
2018 .org objList ; Tell the OP assembler where the list will execute
2020 branch VC < 69, .stahp ; Branch to the STOP object if VC < 69
2021 branch VC > 241, .stahp ; Branch to the STOP object if VC > 241
2022 bitmap bRAM, 22, 70, 24, 24, 22, 4
2023 bitmap bRAM, 20+96+96, 70, 24, 24, 22, 4, 0, REFLECT
2024 scbitmap tms, 20, 70, 1, 1, 8, 3.0, 3.0, 2.9999, 0, 0, TRANS
2025 scbitmap tmsShadow, 23, 73, 1, 1, 8, 3.0, 3.0, 2.9999, 0, 3, TRANS
2026 bitmap sbRelBM, 30, 108, 3, 3, 8, 0, 1, TRANS
2027 bitmap txt1BM, 46, 132, 3, 3, 8, 0, 2, TRANS
2028 bitmap txt2BM, 46, 148, 3, 3, 8, 0, 2, TRANS
2029 bitmap txt3BM, 22, 164, 3, 3, 8, 0, 2, TRANS
2040 RMAC fully supports Motorola's DSP56001 as used on the Atari Falcon and can output
2041 binary code in the two most popular formats: *.lod* (ASCII dump, supported by the
2042 Atari Falcon XBIOS) and *.p56* (binary equivalent of *.lod*)
2044 `Differences from Motorola's assembler`_
2045 ''''''''''''''''''''''''''''''''''''''''
2047 - Motorola's assembler aliases **and #xxx,reg** with **andi #xxx,reg** and can
2048 distinguish between the two. rmac needs the user to be explicit and will
2049 generate an error if the programmer tries to use syntax from one instruction
2051 - Similarly Motorola's assembler can alias **move** with **movec**, **movep**
2052 and **movem**. rmac also not accept such aliasing and generate an error.
2053 - Motorola's assembler uses the underscore character (*_*) to define local
2054 labels. In order for rmac to maintain a uniform syntax across all platforms,
2055 such labels will not be treated as local.
2056 - Macros syntax is different from Motorola's assembler. This includes local
2057 labels inside macros. The user is encouraged to study the `Macros`_ section
2058 and compare syntactical differences.
2059 - Motorola's assembler allows reordering of addressing modes **x:**, **x:r**,
2060 **r:y**, **x:y**. rmac will only accept syntax as is defined on the reference
2062 - In **L:** section a dc value cannot be 12 hex digits like Motorola's assmebler.
2063 Instead, the value needs to be split into two parts separated by **:**.
2067 RMAC will generate code for the MOS 6502 microprocessor. This chapter
2068 describes extra addressing modes and directives used to support the 6502.
2070 As the 6502 object code is not linkable (currently there is no linker) external
2071 references may not be made. (Nevertheless, RMAC may reasonably be used for
2072 large assemblies because of its blinding speed.)
2074 `6502 Addressing Modes`_
2075 ''''''''''''''''''''''''
2076 All standard 6502 addressing modes are supported, with the exception of the
2077 accumulator addressing form, which must be omitted (e.g. "ror a" becomes "ror").
2078 Five extra modes, synonyms for existing ones, are included for compatibility with
2079 the Atari Coinop assembler.
2081 ============== ========================================
2082 *empty* implied or accumulator (e.g. tsx or ror)
2083 *expr* absolute or zeropage
2085 #<\ *expr* immediate low byte of a word
2086 #>\ *expr* immediate high byte of a word
2087 (*expr*,x) indirect X
2088 (*expr*),y indirect Y
2092 @\ *expr*\ (x) indirect X
2093 @\ *expr*\ (y) indirect Y
2095 x,\ *expr* indexed X
2096 y,\ *expr* indexed Y
2097 ============== ========================================
2102 This directive enters the 6502 section. The location counter is undefined, and
2103 must be set with ".org" before any code can be generated.
2105 The "``dc.w``" directive will produce 6502-format words (low byte first). The
2106 68000's reserved keywords (``d0-d7/a0-a7/ssp/usp`` and so on) remain reserved
2107 (and thus unusable) while in the 6502 section. The directives **globl**, **dc.l**,
2108 **dcb.l**, **text**, **data**, **bss**, **abs**, **even** and **comm** are illegal in the 6502 section.
2109 It is permitted, though probably not useful, to generate both 6502 and 68000
2110 code in the same object file.
2112 This directive leaves the 6502 segment and returns to the 68000's text segment.
2113 68000 instructions may be assembled as normal.
2115 This directive sets the value of the location
2116 counter (or **pc**) to location, an expression that must be defined, absolute, and
2121 It is possible to assemble "beyond" the microprocessor's 64K address space, but
2122 attempting to do so will probably screw up the assembler. DO NOT attempt
2123 to generate code like this:
2132 the third NOP in this example, at location $10000, may cause the assembler
2133 to crash or exhibit spectacular schizophrenia. In any case, RMAC will give
2134 no warning before flaking out.
2136 `6502 Object Code Format`_
2137 ''''''''''''''''''''''''''
2138 Traditionally Madmac had a very kludgy way of storing object files. This has been
2139 replaced with a more standard *.exe* (or *.com* or *.xex* if you prefer). Briefly,
2140 the *.exe* format consists of chunks of this format (one after the other):
2145 00-01 $FFFF - Indicates a binary load file. Mandatory for first segment, optional for any other segment
2146 02-03 Start Address. The segment will load at this address
2147 04-05 End Address. The last byte to load for this segment
2148 06-.. The actual segment data to load (End Address-Start Address + 1 bytes)
2153 `When Things Go Wrong`_
2154 '''''''''''''''''''''''
2155 Most of RMAC's error messages are self-explanatory. They fall into four classes:
2156 warnings about situations that you (or the assembler) may not be happy about,
2157 errors that cause the assembler to not generate object files, fatal errors that cause
2158 the assembler to abort immediately, and internal errors that should never happen.\ [3]_
2160 You can write editor macros (or sed or awk scripts) to parse the error messages
2161 RMAC generates. When a message is printed, it is of the form:
2163 "*filename*" , ``line`` *line-number*: *message*
2165 The first element, a filename enclosed in double quotes, indicates the file that generated
2166 the error. The filename is followed by a comma, the word "``line``", and a line
2167 number, and finally a colon and the text of the message. The filename "**(\*top\*)**"
2168 indicates that the assembler could not determine which file had the problem.
2170 The following sections list warnings, errors and fatal errors in alphabetical
2171 order, along with a short description of what may have caused the problem.
2173 .. [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.
2177 **bad backslash code in string**
2178 You tried to follow a backslash in a string with a character that the assembler
2179 didn't recognize. Remember that RMAC uses a C-style escape system in
2182 You specified a label before a macro, **rept** or **endm** directive. The assembler
2183 is warning you that the label will not be defined in the assembly.
2184 **unoptimized short branch**
2185 This warning is only generated if the -s switch is specified on the command
2186 line. The message refers to a forward, unsized long branch that you could have
2193 As a result of previous errors, the assembler cannot continue processing. The
2194 assembly is aborted.
2195 **line too long as a result of macro expansion**
2196 When a source line within a macro was expanded, the resultant line was too
2197 long for RMAC (longer than 200 characters or so).
2200 **memory exhausted**
2201 The assembler ran out of memory. You should (1) split up your source files
2202 and assemble them seperately, or (2) if you have any ramdisks or RAM-resident
2203 programs (like desk accessories) decrease their size so that the assembler has
2204 more RAM to work with. As a rule of thumb, pure 68000 code will use up to
2205 twice the number of bytes contained in the source files, whereas 6502 code will
2206 use 64K of ram right away, plus the size of the source files. The assembler itself
2207 uses about 80K bytes. Get out your calculator...
2209 The assembler ran across an **endm** directive when it wasn't expecting to see
2210 one. The assembly is aborted. Check the nesting of your macro definitions -
2211 you probably have an extra **endm**.
2219 Syntax error in **.cargs** directive.
2221 **.comm symbol already defined**
2223 You tried to ``.comm`` a symbol that was already defined.
2225 **.init not permitted in BSS or ABS**
2227 You tried to use ``.init`` in the BSS or ABS section.
2229 **Cannot create:** *filename*
2231 The assembler could not create the indicated filename.
2233 **External quick reference**
2235 You tried to make the immediate operand of a **moveq**, **subq** or **addq** instruction external.
2237 **PC-relative expr across sections**
2239 You tried to make a PC-relative reference to a location contained in another
2242 **[bwsl] must follow '.' in symbol**
2244 You tried to follow a dot in a symbol name with something other than one of
2245 the four characters 'B', 'W', 'S' or 'L'.
2247 **addressing mode syntax**
2249 You made a syntax error in an addressing mode.
2253 One of your **.assert** directives failed!
2255 **bad (section) expression**
2257 You tried to mix and match sections in an expression.
2259 **bad 6502 addressing mode**
2261 The 6502 mnemonic will not work with the addressing mode you specified.
2265 There's a syntax error in the expression you typed.
2267 **bad size specified**
2269 You tried to use an inappropriate size suffix for the instruction. Check your
2270 68000 manual for allowable sizes.
2274 You can't use .b (byte) mode with the **movem** instruction.
2276 **cannot .globl local symbol**
2278 You tried to make a confined symbol global or common.
2280 **cannot initialize non-storage (BSS) section**
2282 You tried to generate instructions (or data, with dc) in the BSS or ABS section.
2284 **cannot use '.b' with an address register**
2286 You tried to use a byte-size suffix with an address register. The 68000 does not
2287 perform byte-sized address register operations.
2289 **directive illegal in .6502 section**
2291 You tried to use a 68000-oriented directive in the 6502 section.
2295 The expression you typed involves a division by zero.
2297 **expression out of range**
2299 The expression you typed is out of range for its application.
2301 **external byte reference**
2303 You tried to make a byte-sized reference to an external symbol, which the
2304 object file format will not allow.
2306 **external short branch**
2308 You tried to make a short branch to an external symbol, which the linker cannot
2311 **extra (unexpected) text found after addressing mode**
2313 RMAC thought it was done processing a line, but it ran up against "extra"
2314 stuff. Be sure that any comment on the line begins with a semicolon, and check
2315 for dangling commas, etc.
2317 **forward or undefined .assert**
2319 The expression you typed after a **.assert** directive had an undefined value.
2320 Remember that RMAC is one-pass.
2322 **hit EOF without finding matching .endif**
2324 The assembler fell off the end of last input file without finding a **.endif** to
2325 match an . it. You probably forgot a **.endif** somewhere.
2327 **illegal 6502 addressing mode**
2329 The 6502 instruction you typed doesn't work with the addressing mode you
2332 **illegal absolute expression**
2334 You can't use an absolute-valued expression here.
2336 **illegal bra.s with zero offset**
2338 You can't do a short branch to the very next instruction (read your 68000
2341 **illegal byte-sized relative reference**
2343 The object file format does not permit bytes contain relocatable values; you
2344 tried to use a byte-sized relocatable expression in an immediate addressing
2347 **illegal character**
2349 Your source file contains a character that RMAC doesn't allow. (most
2350 control characters fall into this category).
2352 **illegal initialization of section**
2354 You tried to use .dc or .dcb in the BSS or ABS sections.
2356 **illegal relative address**
2358 The relative address you specified is illegal because it belongs to a different
2361 **illegal word relocatable (in .PRG mode)**
2363 You can't have anything other than long relocatable values when you're gener-
2364 ating a **.PRG** file.
2366 **inappropriate addressing mode**
2368 The mnemonic you typed doesn't work with the addressing modes you specified.
2369 Check your 68000 manual for allowable combinations.
2371 **invalid addressing mode**
2373 The combination of addressing modes you picked for the **movem** instruction
2374 are not implemented by the 68000. Check your 68000 reference manual for
2377 **invalid symbol following ^^**
2379 What followed the ^^ wasn't a valid symbol at all.
2381 **mis-nested .endr**
2383 The assembler found a **.endr** directive when it wasn't prepared to find one.
2384 Check your repeat-block nesting.
2386 **mismatched .else**
2388 The assembler found a **.else** directive when it wasn't prepared to find one.
2389 Check your conditional assembly nesting.
2391 **mismatched .endif**
2393 The assembler found a **.endif** directive when it wasn't prepared to find one.
2394 Check your conditional assembly nesting.
2400 **missing argument name**
2402 **missing close parenthesis ')'**
2404 **missing close parenthesis ']'**
2408 **missing filename**
2414 **missing symbol or string**
2416 The assembler expected to see a symbol/filename/string (etc...), but found
2417 something else instead. In most cases the problem should be obvious.
2419 **misuse of '.', not allowed in symbols**
2421 You tried to use a dot (.) in the middle of a symbol name.
2425 The expression you typed involves a modulo by zero.
2427 **multiple formal argument definition**
2429 The list of formal parameter names you supplied for a macro definition includes
2430 two identical names.
2432 **multiple macro definition**
2434 You tried to define a macro which already had a definition.
2436 **non-absolute byte reference**
2438 You tried to make a byte reference to a relocatable value, which the object file
2439 format does not allow.
2441 **non-absolute byte value**
2443 You tried to dc.b or dcb.b a relocatable value. Byte relocatable values are
2444 not permitted by the object file format.
2446 **register list order**
2448 You tried to specify a register list like **D7-D0**, which is illegal. Remember
2449 that the first register number must be less than or equal to the second register
2452 **register list syntax**
2454 You made an error in specifying a register list for a **.reg** directive or a **.movem**
2457 **symbol list syntax**
2459 You probably forgot a comma between the names of two symbols in a symbol
2460 list, or you left a comma dangling on the end of the line.
2464 This is a "catch-all" error.
2466 **undefined expression**
2468 The expression has an undefined value because of a forward reference, or an
2469 undefined or external symbol.
2471 **unimplemented directive**
2473 You have found a directive that didn't appear in the documentation. It doesn't
2476 **unimplemented mnemonic**
2480 **unknown symbol following ^^**
2482 You followed a ^^ with something other than one of the names defined, referenced
2485 **unterminated string**
2487 You specified a string starting with a single or double quote, but forgot to type
2492 The assembler had a problem writing an object file. This is usually caused by
2493 a full disk, or a bad sector on the media.