Date   : Tue, 31 Jan 1989 23:53:10 GMT
From   : mcvax!hp4nl!philmds!nlgvax!geertj@uunet.uu.net (Geert Jan de Groot)
Subject: What format is common for 3.5 inch CP/M disks?

Hello,

Some time ago, I added a 3.5 inch drive to my home-brew CP/M system.
After some testing, it works, so it's time to add the thing in the
BIOS. 

I wonder if there is some standard for 3.5 inch (yes, I know, there
is none officially, as my system uses yet-another-format on 5.25 inch :-),
but would like to know if there is something spread like the OSBORNE-1
format, which seems to be a common standard on 5.25 inch.

So, what format is common among 3.5 inch? I would like to know about
physical sector size, sector numbers, soft/hardware skew, way of 
selecting the next track (next cylinder/other side/interleaved/...), 
DPB, and other things one needs when hacking the BIOS.

Thanks in advance for any responses.

Geert Jan


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Geert Jan de Groot,                    Email: geertj@nlgvax.pcg.philips.nl
Philips Research Laboratories,         Packet: PE1HZG @ PI8ZAA
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