Some said they have CDOS and Cromemco disks
Allison
ajp166 at bellatlantic.net
Fri Apr 15 21:22:42 CDT 2005
>Subject: Re: Some said they have CDOS and Cromemco disks
> From: "Randy McLaughlin" <cctalk at randy482.com>
>Adding a "single-density" drive to a PC does not give you the ability to
>read single density.
There is for all intents no such animal as a "single density drive".
>The PC itself is what needs to be able to handle FM.
Some can, some can't. The 765 FDC core knows both and and *should*
but with the bare 765 chip that requires a bit of external logic around
clocks and data seperators. For the later integrated 765 cores like
the 37C65 it's more a programming issue. One caveat on that is the
slowest rate (125kb/s 5.25 SD) is often not available however if you
have a standalone XT or AT class clard the typical 16mhz clock on the
board can be replaced with a 8mhz (move all the data rates down by 50%).
I have such a hacked board as it was an older one using a 765A and
came with a rare thing, a schematic. However bios support for
such a thing is NOT there and you have to do all the work and even
for an unhacked board the bios may be less than helpful.
Allison
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