I've been thinking about designing an interface card to replace ST-506
>interface drives with ATA (IDE) drives. It's getting hard to find
>Maxtor 2190s at a decent price, and I'm not sure how many more years it
>will be possible to keep them running at all.
>
>The basic concept would be to simply sample the MFM (or RLL) channel
>code at somewhere around 50 MHz as it is being written, and store the
>data on the ATA drive. The interface would keep one track buffered in
>RAM. Whenever the host requests a head change or seek, the buffer would
>be written to the ATA drive (if it is dirty), and reloaded with the data
>for the new track.
>
>This would require a much larger ATA drive than the original drive it is
>emulating, 102K bytes per track. To emulate a Maxtor 2190, this requires a
2G
>ATA drive. You could even emulate drives larger than that by emulating
more
>cylinders.
>
>The tricky part is that it might be necessary for the simulated drive
>to mimic the effect that write precompensation in the host's controller
>is intended to circumvent.
>
>
>
Such a card already exists- I saw someone selling one on the Obsolete
Computer Helpline.
--
-Jason Willgruber
(roblwill_at_usaor.net)
ICQ#: 1730318
<http://members.tripod.com/general_1>
Received on Wed Nov 11 1998 - 19:35:41 GMT