Space, the next frontier

From: Sipke de Wal <sipke_at_wxs.nl>
Date: Tue May 25 16:22:04 1999

Tony Duell wrote:
>
> >
> > On May 24, 18:34, Tony Duell wrote:
> >
> > > Old _working_ ST506 hard disks, however small in capacity should be kept
> > > IMHO. They may be useless in PCs, but there are plenty of machines that
> > > can use such drives but can't use IDE/SCSI/whatever. And it's getting
> > > ever harder to get working ST506 drives.
> >
> > Having just spent several days obtaining a suitable 20MB ST506-interface
>
> Several days? That's pretty quick.... I've spent months looking for
> working ST506-interfaced drives in the past....
>
> > hard drive, I completely concur with Tony. The 3.5" versions seem to be
> > particularly hard to come by around here.
>
> The other 'nasty' is machines that will only take a limited number of
> hard disk types (geometries). Sometimes only 2 or 3 drives are supported,
> and you can bet that they'll either be almost impossible to find a drive
> with all parameters in excess of the ones needed, or it will actually
> verify that the drive has the specified geometry (e.g. checking that a '6
> head' drive doesn't work when heads >5 are selected). Getting the right
> spare drive for one of those can really drive you insane.
>
XT/PC RLL/MFM controllers sometimes have a setup program that can cater
for more than one geometry. Use debug and jump to c800:000x where x can
be anything from 0-8. You might see a harddisk lowlevel
configuration/formatting utility.

c800 = c800 when the controller ROM was mapped there by default but some
systems may have that altered.

Sipke de Wal
Received on Tue May 25 1999 - 16:22:04 BST