+++ /dev/null
-
- a56 - a DSP56001 assembler - version 1.2
-
-/*
- * Copyright (C) 1990-1994 Quinn C. Jensen
- *
- * Permission to use, copy, modify, distribute, and sell this software
- * and its documentation for any purpose is hereby granted without fee,
- * provided that the above copyright notice appear in all copies and
- * that both that copyright notice and this permission notice appear
- * in supporting documentation. The author makes no representations
- * about the suitability of this software for any purpose. It is
- * provided "as is" without express or implied warranty.
- *
- */
-
-V1.2 CHANGES
-
-Contributors to V1.2 -
-
- Andreas Gustafsson <gson@joker.cs.hut.fi>
- - Added DS and DSM directives
- - Generalization of the use of "*" allowing current program counter
- to be used in any expression (including "org l:*" which is useful
- for changing spaces without changing the PC)
- - Noted a bug with MOVEP to a non-symbolic I/O address. I believe
- this is now fixed.
- - Noted that mispelled argumentless operators will be treated as
- labels. For example, N0P (N-zero-P) will be treated as a label.
- Unfortunately, my own use of a56 (i.e. using cpp as the macro
- pre-processor) complicates this. However, the grammar might
- have been simpler if the lexical analyzer was able to distinguish
- between label declarations and references instead of leaving that
- up to the YACC parser.
-
- Tim Channon <tchannon@black.demon.co.uk> and Peter Breuer
- <ptb@comlab.ox.ac.uk>
- - Missing ";" in grammar!
-
- Rober Ganter <ganter@ifi.unibas.ch>
- - Fixed bad comment on line 10 of a56.y
-
- Me <jensenq@zdomain.com>
- - Listing now includes psect usage summary
- - Better checking of movec arguments
- - Added int(value) function to convert floating point constant expression
- to integer (by truncation)
- - Correctly convert a floating -1.0 to 0x800000
- - Wrote a new lexical analyzer and lexical parser generator
- - Many other minor enhancements and fixes.
- - Ported to DOS using DJ Delories' GCC port. (Tools available at
- ftp://omnigate.clarkson.edu/pub/msdos/djgpp)
-
-Known bugs/deficiencies:
-
- - MOVE to a control reg generates bogus code (always use MOVEC,
- MOVEM, and MOVEP)
-
-The example code this time around includes a full six-comb stereo reverb
-(based on Moorer). This one sounds a lot better than the four-comb algorithm.
-Each comb uses a one-pole low-pass filter in the loop. It lacks the
-early-reflection FIR (although Motorola's rvb2.asm has it) but has
-true stereo decorrelation by using a twin allpass stage. My old reverb
-just used inversion to simulate stereo (the whole reverb effect would
-disappear if you mixed the outputs). I've included only actual reverb
-code itself. It lacks the hardware-implementation-specific shell.
-
-
----------------------------------------------------------------------------
-
-OVERVIEW
-
-This program was written as a vehicle to learn the intricacies
-of the DSP56001 instruction set, and to provide a tool for Unix-based
-DSP code development (for those of us without a NeXT machine.)
-
-The intent was to provide compatibility with Motorola assembler's syntax.
-But since the author did not have Motorola's assembler or its documentation,
-it is no doubt far from compatible. Only a few pseudo-ops are implemented--
-probably only partially.
-
-Macros are not supported, except through the use of an external macro
-preprocessor, such as /lib/cpp. To facilitate cpp macro expansion, multiple
-assembler statements on a single input line are delimited with an '@', e.g.:
-
- #define JCHEQ(c,label) move #c,x0 @cmp x0,a @jeq label
-
- #define JCHNE(c,label) move #c,x0 @cmp x0,a @jne label
-
-
-SUPPORTED PSEUDO-OPS
-
-The following is a list of the pseudo-ops that are recognized:
-
- <symbol> = <expression> ;assign a symbol
- <label> EQU <expression> ;ditto
-
- ALIGN <number> ;set location pointer
- ;to next integral
- ;multiple of <number>
-
- ORG <space:> <expression> ;new location pointer
- ORG <space:> <expression>, <space:> <expression>
-
- DC <dc_list> ;declare constants
-
- DS <number> ;reserve <number>
- ;words of space
-
- <label> DSM <number> ;reserve space for
- ;properly aligned
- ;modulo-addressed
- ;buffer of size
- ;<number>, assigning
- ;the aligned starting
- ;address to <label>
-
- PAGE <number>, <number>, <number>, <number> ;ignored
-
- INCLUDE <file> ;file inclusion
-
- END ;end
-
-In addition, a "PSECT" pseudo-op was implemented. It allows program sections
-to be defined and bopped in and out of, each with its own location counter and
-space. The Motorola assembler probably does not have this pseudo-op, but no
-doubt supports the concept in some way.
-
- PSECT <name> <space:><begin_addr>:<end_addr> ;define
-
- PSECT <name> ;switch to psect <name>
-
-
-FUTURE DIRECTION
-
-The assembler probably generates bogus code here and there, and no doubt
-does not handle all of the syntax. I welcome all comments, fixes and
-enhancements.
-
-TO MAKE AND USE
-
-Type "make".
-
-The resulting program, a56, is used as follows:
-
- a56 [-b] [-l] [-o output-file] file [...]
-
-An assembler listing is sent to the standard-output and an ascii-formatted
-object file (a56.out) is produced. The "-b" option adds binary to the listing.
-"-l" causes included files to be listed. "-o" directs the output to the
-specified file rather than the default, a56.out.
-
-A separate program, toomf, converts a56.out into "OMF" format suitable for
-downloading to the 56001 via the sloader.a56 program.
-
- toomf < a56.out > file.omf
-
-AUTHOR
-
-11/28/91
-v1.1 8/6/92
-v1.2 5/2/94
-
-Quinn C. Jensen
-1374 N 40 E
-Orem, UT 84057
-
-home: jensenq@zdomain.com (preferred address for a56 correspondence)
-work: jensenq@novell.com
projects / linux-libre-firmware.git / blobdiff