Documentation on DEC's Omnibus Module M865 (Console Teletype Control)

krause at krause at
Thu Mar 3 10:24:51 CST 2016

On Thu, 3 Mar 2016, Christian Corti wrote:
> It's online now at 
> Christian

I moved the scans in a lower directory

I also added a scan of a clever modification, that the foreowners of the
machine made 40 years ago:
They had two serial interfaces, one M865 and one M8650 with the same I/O-
address 03/04.
Only one at a time is active, controlled by "SW" on the frontpanel:
"SW" up:   9600Bd - M8650
"SW" down: 110Bd current loop M865

The modification on the M865 is simple, the modification on the M8650
is more complicated as they added also hardware flowcontrol. They added
an additional 7400 (E49) on the board.
Picture M8650_switch_1.jpg is a first version, which they modified some
days later to M8650_switch_2.jpg.


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