Hi guys,
I'm trying to track down a copy of the schematics (if any still exist)
for the DMA Data LSI used in the AT&T Unix PC (aka the AT&T 3B1 or AT&T
7300).
The Technical Reference Manual scans which were posted here earlier
include the DMA Address LSI, but not the DMA Data LSI. Unfortunately
about 80% of the DMA logic is in.... *drumroll*... the Data LSI. The
Address LSI is basically a glorified presettable up-counter.
These should be in the AT&T UNIX PC Technical Reference Manual, if
anyone has a copy kicking around. I already have the DMA Address LSI,
Video LSI, 512k Motherboard, 1MB Motherboard and 2MB Motherboard
schematics.
Thanks,
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/