bridger%rcc@RAND-UNIX.ARPA (Bridger Mitchell) (12/08/87)
DU uses direct bios file i/o to access disk sectors. It's an example of a program that needs repackaging to run under cp/m 3. To use it, get CPM2RSX (or similarly-named RSX) and use the CP/M 3 utility to encapsulate a COM file with that RSX. That particular RSX converts cp/m 2.2-style direct bios io calls to cp/m 3 calls via the dos AND provides full physical->logical sector deblocking. However, as noted previously, you can't just put a zcpr3 cp/m 2.2 type command processor on the boot tracks of a cp/m 3 system and go; it requires rebuilding the interface from the ground up.
ciaraldi@cs.rochester.edu (Mike Ciaraldi) (12/09/87)
In article <8712082023.AA08132@newton.arpa> bridger%rcc@RAND-UNIX.ARPA (Bridger Mitchell) writes: >DU uses direct bios file i/o to access disk sectors. It's an >example of a program that needs repackaging to run under cp/m 3. >To use it, get CPM2RSX (or similarly-named RSX) and use the >CP/M 3 utility to encapsulate a COM file with that RSX. > >That particular RSX converts cp/m 2.2-style direct bios io calls >to cp/m 3 calls via the dos AND provides full physical->logical >sector deblocking. Am I missing something? The newest version of DU I have seen, version 8.9 (from sometime in 1984), is supposed to check whether it is running on CP/M 1.x, 2.x, or 3.x, and adjust accordingly. For example, it uses direct BIOS calls for 1 and 2, but uses BDOS function 50 to do its BIOS calls in 3. Meanwhile, I am in the process of converting DU to run on my MP/M system. Has anyone already done this? BTW, I assume we are talking about the same "DU"--the disk utility which lets you read, write, and modify any sector on the disk. Mike Ciaraldi arpa: ciaraldi@cs.rochester.edu uucp: seismo!rochester!ciaraldi
bridger%rcc@RAND-UNIX.ARPA (12/13/87)
Mike, My face is (seasonally?) red. The generic DU does, indeed, check for CP/M 3 and use BDOS function 50. I had been testing with "DU3", a Rick Conn variant of DU that has only CP/M 2.2 capability. CP/M 3 users should use generic DU. When ZCPR33 is released for CP/M 3, DU3 users will be able to run that version under an RSX. --bridger