On 06/12/2008 16:23, Philipp Hachtmann wrote:
G104 X/Y drivers
G227 Sense/Inhibit
G619A 4K core stack
The 4K stack is broken and lost forever.
But I have a spare G646C "4K or 8" Stack sitting around.
I *think* it has 8K.
There should be a sticker, usually a white paper DEC sticker but
sometimes a silvery sticker, on the back, with a DEC part number. 8Kx12
stacks say H212 or H212A.
Does anyone know if I could use that stack with the
rest of the package,
using only 4K of the memory?
Does anyone have schematics for the 8K core system? In my documentation
I have only information about the 4K system.
I don't know if you can use that stack with the 4K drivers and
sense/inhibit card, but the print set with schematics for the 8K system
(MM8-EJ) is on David Gesswein's site and mirrored at Highgate. So is
the one for the 4K (MM8-E), which seems to include MM8-EJ diagrams.
http://www.pdp8online.com/pdp8cgi/query_docs/view.pl?id=243
You could compare the top connections to the 4K schematics. I'd be
interested to know myself. The notes on the 8K schematic list
compatibilities that don't include the 4K drivers etc, but that may only
be because you wouldn't get the full 8K with 4K drivers or sense/inhibit
controllers.
--
Pete Peter Turnbull
Network Manager
University of York