25 Nov
2006
25 Nov
'06
10:41 a.m.
On 25 Nov 2006 at 14:20, Dave Dunfield wrote:
I didn't mention the Tarbell - I was going by the
subject line.
My bad--I ignored the number of right-pointing doohickeys in the post-
-it was Jim who mentioned the Tarbell.
It's a complete hardware (no chip) floppy
controller - knowing how it works,
I think you would be very hard pressed to successfully home the head and
read a sector in 32 bytes.
Probably so--and perhaps it was cheaper to do that way, given the
soft-sectored alternatives. Intel used a two-board 3000-series bit-
slice implementation on the MDS and IMSAI used a two-board 8080
implementation on theirs. (I never could get the IMSAI controller
working reliably enough for everyday use.) Even the WD1691 and 1771
were very expensive items when they first appeared.
Cheers,
Chuck