29 Nov
1999
29 Nov
'99
12:26 p.m.
-----Original Message-----
From: Al Kossow <aek(a)spies.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Monday, November 29, 1999 10:05 PM
Subject: Re: Needed: 1 IBM 8" alignment disk.
It is... *really* dumb... Its got a 2 sector buffer option(claims it can do
2 things at the same time with the buffers) so I got a bigger really dumb
controller.
It's search algorithm is really funny too:
Read Sector <-------------
If requested Sector <> address then |
If CRC not okay then ---------------------|
(you get the idea.. and infinite loop for most errors)
john
PDP-8 and other rare mini computers
http://www.pdp8.com
"I wonder if it really is working most of the way
(i.e. it can read ID
marks and even data) but there's a problem getting that read data to the
CPU (shift registers, bus drivers, etc)."
Are you trying this on your 8/I or 8/S ?
The PDP-8i.. (it works the same on both units).. This drive has a dual
buffer (50) and was made to be used on some of the slowest computers... The
manual claims from high speed to "DC"... I have it on the 8i as I don't
like
to subject the 8/s to questionable hardware.
From memory, the Sykes interface is REALLY dumb.
An 8/S might be too slow
to handle the data rates..