What's a WD2793A chip? - test-drb@ccmp.vtda.org

4 Feb 2000

A 1781? !!GAWD!! I've not seen even an oblique reference to that number
since back in the '70's.  Wasn't that the one that died with MMFM?  I
don't
believe I ever saw one in the "flesh."  Nevertheless, the difference between
it and any other member of the WD 8"-drive-capable controller line is
probably pretty minor.

Dick
-----Original Message-----
From: Dwight Elvey &lt;elvey(a)hal.com&gt;
To: classiccmp(a)classiccmp.org &lt;classiccmp(a)classiccmp.org&gt;
Date: Friday, February 04, 2000 3:09 PM
Subject: Re[2]: What's a WD2793A chip?

...
 "Richard Erlacher" &lt;edick(a)idcomm.com&gt;
wrote:
> That's correct, Eric, it's a direct replacement, functionally, for the
1793,
...
 > with an analog clock extraction circuit.  It has
the limitation that the
> analog clock processing circuit requires a different lowpass filter for
8"
...
   and
5-1/4" drives, and, IIRC for FM or MFM. 
Hi
 I have a iSBX card that I wrote a driver for that uses a
2793. It is software compatable with the 1793. It does
1.44M disk with the right clock. What I'd like to
know is what are the software requirements for a 1781?
Dwight