Date   : Tue, 10 Apr 1990 00:25:27 GMT
From   : zephyr.ens.tek.com!gvgpsa!gold!grege@uunet.uu.net (Gregory Ebert)
Subject: 3.5" on 8" Controller?

I have looked into putting a 3.5" on my 8" controller, and the only
differences I could find are (1) the MOTOR_ON signal for the 3.5" 
drive -- it can be tied to DRIVE_SELx on the 8" drive, and (2) the
3.5" drive has seperate signals for DIRECTION and SIDE_SELECT, whereas
the 8" drive 'muxes' them. The data rates are identical. You will need
to tweak the stepper rate for the head.

There is (was ?) a 5.25" drive by Mitsubishi which is (was?) electrically
interchangeable with a 8" DSDD drive. It could store up to 1.6MB formatted.

Unfortunately, having just moved, gotten a new job, and being a new
first-time daddy, I haven't had time to _actually_ do it yet. As soon
as the &^%#@&$ doctor bills are paid, I'll snag a drive and try it.