Date   : Thu, 28 Mar 1991 20:50:36 GMT
From   : swrinde!zaphod.mps.ohio-state.edu!caen!umich!terminator!pisa.citi.umich.edu!rees@ucsd.edu (Jim Rees)
Subject: Want to swap 5 inch to 8 inch floppy

This has nothing to do with CPM, but I understand you guys are the experts
on floppy drives.  I've got a computer (Apollo dn330) that has an 8 inch
floppy drive that I want to change to a 5 inch.  The 8 inch has a capacity
of 1.2 Mb, something like a st506 interface (sa850?), and a 50 pin card-edge
connector.  I've got pinouts for the 50-pin and also for the 34-pin
connector used by the 5 inch drives.

I'm told that the rotational speed is the same, and I know the sector layout
is the same, so I'm assuming that bit rates and signal timings will just
fall out for free.

1.  Will this work?

2.  Is there any chance this will just plug-n-play, or will I have to muck
around with the device driver in the OS?

3.  What do I do with pin 2 (density) on the 34-pin?  I assume tie it high
or low -- which is it?

4.  What about pin 16, motor-on?  Should I tie this high or low, or tie it
to pin 4, head-load?

5.  What is pin 2 on the 50-pin, RWC?  What should I do with it?

6.  Any tips on shopping for a 5 inch drive?  Will any drive with the 34-pin
(sa450?) connector work, as long as it's a 1.2 Meg drive?  How much should a
floppy cost?  The local repair shop has one for US $60, is that OK?


End of INFO-CPM Digest V91 Issue #65
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