Re: annc: GS/OS AppleDisk5.25 Project

["Peter Watson" <paw77@N_O_hotmail_S_P_A_M.com>]

The 5.25" drives were connected to the standard controller. It's been a 
while but as far as I know CP/M disks used a standard 16-sector low-level 
format, meaning they could be copied by any utility that copied an entire 
disk image. Obviously the contents of the sectors would be unintelligible to 
any DOS, Pascal or ProDOS file-based utility (that didn't have specific 
support for CP/M disks).

The only low-level difference I'm aware of is that the sector interleave was 
unique to CP/M disks.

Physical: 0 1 2 3 4 5 6 7 8 9 A B C D E F
DOS:      0 D B 9 7 5 3 1 E C A 8 6 4 2 F
Pascal:   0 2 4 6 8 A C E 1 3 5 7 9 B D F
CP/M:     0 3 6 9 C F 2 5 8 B E 1 4 7 A D

ProDOS uses the same interleave as Pascal.
CP/M disks used a 1K allocation unit, so information is stored in four 
"consecutive" sectors, for example: 0 3 6 9.
-- 
Peter Watson
-- Write to MS-DOS disks on the Apple IIgs?
-- Impossible!  ;-)


"Toinet" <antoine.vignau@laposte.net> wrote in message 
75f76ad7-8489-4311-958c-0288c96d84af@z28g2000prd.googlegroups.com">news:75f76ad7-8489-4311-958c-0288c96d84af@z28g2000prd.googlegroups.com...
On 15 nov, 00:21, Steven Hirsch <snhir...@gmail.com> wrote:
> Great project! Since day one with GSOS I've wanted an FST for Apple CP/M
> format. I don't think Apple ever released a shred of information on the 
> API
> for FSTs, so it's likely to be a lot of disassembly.

I would rather say that we can now create FSTs (see our RDOS FST) but
I will focus on the CP/P disks which I have never had between my hands
but I know where they are on Asimov.

Nevertheless, those disks are 140 KB long, 35 tracks of 16 sectors,
just like our Pro/DOS disks but were these disks copyable with
Locksmith? Were the disk drives connected to the CP/M card or do the
Apple II disk controller card?

Any other info on the "physical" disk format interest me. The
A2.CPM.ref.txt found on asimov is a good starting point.

Thank you,

antoine