18 Jun
2019
18 Jun
'19
10:47 p.m.
On Wed, Jun 19, 2019 at 1:00 AM Al Kossow via cctalk
<cctalk at classiccmp.org> wrote:
came across these this eve, probably only of interest
to Seth, since he has one
http://bitsavers.org/pdf/att/5620/schematic
I have one too (from a friend who used to work in the Columbus Bell
Labs Operating System Group (cbosg)). I found the read-through to be
quite illuminating, especially the detail on the keyboard circuit
(4800 bps TTL levels off one channel of the DUART). I do have a
keyboard but this info makes it simple to contemplate a keyboard
adapter for those that do not.
Thanks for posting this, Al.
-ethan