Path: utzoo!utgpu!water!watmath!clyde!rutgers!husc6!bbn!uwmcsd1!ig!agate!ucbvax!EMX.UTEXAS.EDU!mknox
From: mknox@EMX.UTEXAS.EDU (Margaret H. Knox)
Newsgroups: comp.os.cpm
Subject: Re: DosDisk for CP/M-68K (ref: RSX modules)
Message-ID: <8802150401.AA15247@emx.utexas.edu>
Date: 15 Feb 88 04:01:29 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 16


With reference to Bridger Mitchell's comments about porting DosDisk
to CP/M-68K (Z-80 assembly language running as RSX routine):

CP/M-68K does indeed support RSX modules (I have written a number of
them), although the total DRI documentation on them in the 68K manual
consists of the statement that they are supported.

I should point out however that porting a Z80 assembly language
program to the 68000 is non-trivial.  Better off to look at the
Z80 code and use that as a template to re-write the program.  The
biggest problem is that the Z80 (and 8080) does not update the CC
for a number of common instructions.  A straight transliterated
version will spend a lot of time saving and restoring
(uselessly) the CC.  Only other solution is to look at every
conditional and see where the CC was actually determined.