13 Jun
2010
13 Jun
'10
7:24 p.m.
On 6/13/10 12:31 PM, Alexandre Souza - Listas wrote:
I only have one picture that shows the boards, it's a NASA "publicity
shot". It can be seen here:
http://www.neurotica.com/misc/NSC-sm.jpg
The big RAM boards I was talking about above are the four rearmost
boards in the rightmost group, and were not yet complete when that
picture was taken. They used 51C256 DRAM chips with i8207 DRAM
controllers. The machine had a 36 bit word (32 data bits, 4 tag bits)
and the memory arrays were 4MW, so 576 chips per board.
The astute person will recognize the Unibus form factor boards and DEC
chassis. We bought their "OEM" chassis which were just racks, chassis,
power supplies, and completely un-wrapped backplanes. The boards are
only physically identical to Unibus boards, there are no bus
compatibilities of any kind, or any DEC compatibility at all for that
matter...we simply used a convenient board shape and size for which very
high-quality chassis and backplanes were readily available.
That picture was taken in 1987. I'm the guy on the left in the rear
row wearing the Adidas T-shirt, if anyone cares. I was 18 at the time.
-Dave
--
Dave McGuire
Port Charlotte, FL
A project I
worked on in those days had four RAM boards each
containing 576 51C256 chips. I remember thinking for a split second
"Hmm, how could I get one of those boards out of here?" ;)
I got **very** curious of what it could be :D 576 ram chips are a lot
of chips for one board :D Pictures? :D 