I've recently acquired a TORCH-725 which has this RO200
series hard drive in it, trouble is when I took everything
out of the TORCH case for first inspection I heard something
'ting' off one of the platters in the drive. Opening it up
to have a look, well a little dust can't be as bad as debris
that goes 'ting', I found a 12mm long 2.7mm dia. roll pin
lying in one corner. Anyone have a clue where this may have
come from? Dare I power the drive without it? This may
No real idea.... Look for a hole that could have taken it, I guess.
Obvious candidates would be an end stop for the head movement, part of a
flexiprint guide, or part of the positioner itself (am I correct that
this drive uses a stepper motor to position the heads?)
eventually be the only option if I can't
re-install the pin.
While this is an RO200 series I don't know which one. The
series seems to run from 5MB to 40MB and I'd like to know
which one this is likely to be.
Assuming this drive needs to be replaced can I use a 40MB
SCSI drive on the Torch SCSI board and bypass the SCSI to
ST506 interface? This would be the prefered eventual solution
I doubt it. Most Torch machines used an OMTI 5000 series board, I think
(the XXX certainly did, I think the rare SCSI plinth for the Beeb did
too). Said board certainly supports multiple 'units' at one SCSI address
(do most SCSI drives fo that). There's also something about reading the
drive geometry from the first (zeroth?) sector of the drive, then sending
some commands to the OMTI board. I doubt that modern SCSI drives will
handle that correctly.
-tony