X-Git-Url: https://jxself.org/git/?p=a56.git;a=blobdiff_plain;f=README;fp=README;h=0a369be7c37eac4b19db887b1b6b006ef0505903;hp=0000000000000000000000000000000000000000;hb=c6db6f4c5cb82f5e09472163bf11be0c165965ee;hpb=6539332686a03e95d8032567093e2297ba6748a7

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+a56 - a DSP5600X assembler
+---------------------------------------------------------------------
+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
+
+Known bugs/deficiencies:
+- MOVE to a control reg generates bogus code (always use MOVEC,
+  MOVEM, and MOVEP)
+
+Wish list
+- Add support for new instructions and modes
+
+AUTHOR
+Quinn C. Jensen
+1374 N 40 E
+Orem, UT  84057
+
+http://www.zdomain.com/~jensenq/
+
+home: jensenq@zdomain.com (preferred address for a56 correspondence)
+work: jensenq@novell.com
+
+Copyright (C) 1990-1998 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.
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