H89 CP/M hard-secored boot diskette

From: Don Maslin <donm_at_cts.com>
Date: Thu Apr 3 00:27:01 2003

On Wed, 2 Apr 2003, Patrick Rigney wrote:

> > [Tony wrote:]
> > Very odd...
> >
> > You might try checkking the index monostables on the hard sector
> > controller (they only really do anything once per track, when the index
> > hole between the sector holes comes round), but I can't see why it would
> > then work for the first 4 cylinders.
>
> Well, as it turned out, the stepper motor on the drive was locking up. The
> further towards the inner tracks it got, the more it struggled, and it
> wasn't close to correctly centering over any track beyond the first few.

You might want to check and/or clean the guide rails for the head
assembly to assure that they slide with little effort, if you have
not done so already. I have seen similar problems a number of
times as a result of 'sticky' rails.
                                                - don

> I'll mess with that later. I was able to replace the drive with a spare,
> and I'm again up and running. I produced several good test boot disks, BUT,
> I don't know how well that new drive is aligned, it's straight off the shelf
> from the As-Is room at Wierd Stuff. Rotation speed is spot-on according to
> the internal diag, but I don't have a 5.25" alignment disk to check it
> otherwise. Anyone who receives a boot disk from me is, therefore, going to
> be my "canary in the mine." :-)
>
> Next task... get the soft-sectored controller running. Unfortunately I have
> no docs for this whatsoever, not even a schematic. I understand that it
> requires MTR-90, and possibly a certain HDOS software distribution as well.
> Does anyone know?
>
> Patrick
Received on Thu Apr 03 2003 - 00:27:01 BST

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