[comp.os.cpm] What format is common for 3.5 inch CP/M disks?

geertj@nlgvax.UUCP (Geert Jan de Groot) (02/01/89)

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


-.-.- --... ...--   -.. .   .--. . .---- .... --.. --. .-.-.

Geert Jan de Groot,			Email: geertj@nlgvax.pcg.philips.nl
Philips Research Laboratories,		Packet: PE1HZG @ PI8ZAA
Project Centre Geldrop,			AMPRNET: [44.137.24.3]
Building XR, Room 15,
Willem Alexanderlaan 7B,		"When in doubt,
5664 AN Geldrop, The Netherlands.	 tune for minimum smoke
phone: +31 40 892204			 and then consult a reference"
[Standard disclaimers apply]		-(Found in a manual)