Date : Sun, 14 Feb 1988 22:01:29 CST
From : mknox@emx.utexas.edu (Margaret H. Knox)
Subject: DosDisk for CP/M-68K (ref: RSX modules)
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.
End of INFO-CPM Digest
******************************