15 Feb
2015
15 Feb
'15
12:32 p.m.
MARCH's PERQ-1 is missing the keyboard and control tablet. Does anyone
have those that we could borrow, in order to bring up the system? We're
looking to work on it in June this year.
If it's any help, the PERQ 1 (and 1A) tablet is a standed GPIB-interfaced
Sumagraphics Bit Pad 1.
The keyboard is a custom unit, of course. It's an 8 bit parallel output (+strobe),
the bottom 7 bits are the key ASCII code (most of the time) and the top bit is the
control key (!). The keyboard unit also contains the system reset button (just grounds
one of the pins on the connector) and the DDS display, which is a 3 digit decimal
up-counter + display, it counts the pulses on another pin of the connector and is
reset by the reset button.
I should be able to find more detailed information if you can't get the original
keyboard and are forced to kludge something up.
-tony