16 Nov
2007
16 Nov
'07
1:29 a.m.
On Thu, Nov 15, 2007 at 05:14:34PM -0800, Geoff Reed wrote:
the C= disk drives were pretty much all smart drives
weren't they?
Yes.
the big dual drive units had a controller card in
them that was
basically a small computer (IIRC)
"Controller card" might not be the best term, but yes, there was a
one board inside with one or more 6502-family microprocessors
(depending on the drive model). Older, dual drives tended to have
a couple of processors (6504s were common) with a few K of shared
memory; newer drives tended towards one microprocessor (a full 6502
was common), with a software scheme to simulate the multi-processor
model of the older drives.
The older, dual drives also had one analog board for both drive
mechanisms. Newer drives had the analog circuitry on the mainboard
with the processor.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 16-Nov-2007 at 01:20 Z
South Pole Station
PSC 468 Box 400 Temp -40.9 F (-40.5 C) Windchill -68.0 F (-55.6 C)
APO AP 96598 Wind 9.7 kts Grid 139 Barometer 680.6 mb (10606 ft)
Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html