20 Nov
2009
20 Nov
'09
11:22 p.m.
Fred Cisin wrote:
Will your circuitry be able to handle the doubled data
transfer rate?
The acquisition clock rate is 40MHz. That means every clock tick in the
acquired timing data represents 25 nanoseconds. My current torture-test
is to feed it a 10MHz "read data" signal, which it's handling fine. It's
actually having more trouble with the slower bit rates because there are
one or two little issues with the pseudo-RLE compression.
I seem to recall mentioning that it'll read MFM hard drives, which
typically have a 5Mbps data rate. 1Mbps should not be an issue. You'll
have more trouble soldering the adapter cable together than you will
getting a valid data readback!
I think that the first 34 pins are the same. I only
have a few of those
drives, and they are many archeological layers deep. The pinout of the
ones that IBM used on the PS/2s (with the 6 extra pins for power) might be
in the AT "Options and Adapters" Tech Ref
Knowing IBM, I wouldn't be surprised. I think my 2.88 drive is buried in
a box somewhere (it was "liberated" from a dead PS/2 of some
description) but I don't have any discs for it.
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/