MPI-52 as replacement for SA400?

From: Don Maslin <donm_at_cts.com>
Date: Thu Jan 1 01:09:27 1998

On Thu, 1 Jan 1998, Bill Richman wrote:

> Is the SA-400 the standard Northstar floppy drive? I've been running
> a Northstar floppy controller in my IMSAI, using just a couple of
> plain old IBM-XT floppy drives. I was clued in by someone else on
> this list that they would work, and they seem to be fine; even
> handling the original hard-sectored diskettes! I was under the
> impression that the sectoring was at least in part determined by the
> drive, but have been told (and have seen for myself) that this is not
> so; it's determined by the controller. Hope this helps!

You are correct, Bill. I have substituted a half-high 720k 5.25" drive
for the full high 100tpi drive on a 16-hard-sector Vector Graphics quite
successfully.

> On Tue, 30 Dec 1997 19:37:37 -0600 (CST), you wrote:
>
> >
> >I've got a Northstar Horizon that I'm starting to restore. The Northstar
> >manual indicates that the Northstar disk controller wants to talk to one
> >or two SA400s, which sounds about right considering the time period.
> >
> >Problem is the only SA400s, or similar, that I have are in my SWTPC 6800
> >and I don't want to pull them. I know that the SWTPC will accept an
> >MPI-51 as a replacement for an SA400 (but not an SA400 on a controller
> >that expects to see MPI-51s since they have a slightly higher step rate).
> >
> >Could I use an MPI-52, and under what conditions, as a replacement for
> >the SA400s that the Northstar wants to see? If so, why? If not, why not?
> >
> >Thanks...
> >
> >Anthony Clifton - Wirehead
>
>
> -Bill Richman
> bill_r_at_inetnebr.com
> http://incolor.inetnebr.com/bill_r
>
> -------------------------------------------------------------------------------
> "When they took the fourth amendment, I was quiet because I didn't deal drugs.
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> -www.paranoia.com
>
                                                 - don
    donm_at_cts.com
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    Don Maslin - Keeper of the Dina-SIG CP/M System Disk Archives
         Chairman, Dina-SIG of the San Diego Computer Society
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Received on Thu Jan 01 1998 - 01:09:27 GMT

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