Disk hardware emulation, was Re: Grandfather system RTE6/VM?

From: Peter C. Wallace <pcw_at_mesanet.com>
Date: Mon Dec 1 12:45:12 2003

On 1 Dec 2003, Jules Richardson wrote:

> On Mon, 2003-12-01 at 16:32, Andreas Holz wrote:
> > Hello all,
> >
> > I would like to see a substitution of the now rapidly dying
> > MFM/SMD-disks. I would appreciate if I could swap out a defective
> > Maxtor-XT/ drive, and an IDE-drive into my Symbolics or PDP simply by
> > connecting the "black-box" to the existing cables.
>
> Agreed. Or given the capacity of modern (ish) IDE/SCSI drives versus old
> hardware, being able to host several virtual drives on one physical one
> would be interesting, not waste drive space, and make it trivial to back
> systems up.
>
> Several machines' drive controllers could be interfaced across a network
> to one host. The "black-boxes" would talk ST506 on one side and ethernet
> on the other, say.
>
> Interesting idea anyway... but given the nature of ST506 is it feasible?
> Doesn't ST506 have analogue elements to the interface, and a tight
> relationship to the host controller with which the drive was formatted?



No, there are no analog elements other than timing, and that can be simulated
digitally with sufficient resolution to fool the controller. MFM drives and
many earlier types should be pretty easy to emulate. Think of the emulator
(one track at a time) as just a big shift register clocked at ~16X the drive
data rate...


>
> cheers
>
> Jules
>

Peter Wallace
Received on Mon Dec 01 2003 - 12:45:12 GMT