Interesting. I think these came from that E-COM US Postal Service thing
in the late 1980's where the USPS built a pilot system to allow you to
go into a post office, give them a letter, then they would scan the
letter, route it through a network of pdp11's to the destination PO
where it was then printed out and delivered. Yes, I think this was when
a Fax machine was a very very big thing.
Interesting part is they used these boards for interconnections. The
actual node was a pdp11/23 CPU with 256kb of memory, one or more of
these things (which if I recall could handle 8 serial lines each), a
multifunction board with clock, parallel interface (for printer), serial
ports, and of course a pair of RM02 disk drives.
Before you consider that to be an impossible system, each system had a
special Plessy bus in a BA11 type chassis that had a voltage regulator
to make the +12, a Q bus/Unibus backplane that had a Plessy Quineverter
to talk to the Unibus stuff. Even the RM02 so the Quniverter did have
DMA capability but I don't recall if it has a unibus map (I have one or
two of those here somewhere as well. I have a lot of stuff)
This is how Doug and I met at Alan Frisbee's place in Greenbelt to split
a horde of RM02 disk drives and other stuff. Man this is going back
years, but I think I still have a lot of the documentation for this
project somewhere in the paper piles, it was a weird concept.
On 10/7/2020 12:36 PM, Al Kossow via cctalk wrote:
On 10/7/20 8:29 AM, Chris Zach via cctalk wrote:
That sounds like it, and I might have been the one to upload the
drivers. Let me find one in the shed and take a picture.
https://pubs.usgs.gov/of/1988/0185/report.pdf
https://pubs.usgs.gov/of/1991/0262/report.pdf
from Larry Baker
they were popular X.25 cards that had BSD support
I think that's what we used at Apple to get on NSFnet
