Data General Dasher D1 - pinout information...

Dear folklorists, recently I got hands on a "Data General Dasher D1", DGC Part number DGC 002 005116. Today I roestored it and analyzed how it works. For those interested, here a short description: (a) PCB made by Keytronic Corp. KTC in 10/1979, Part. No. A65-01538-01. (b) On this are some well known Chips (7474, 7437 74123, ...) and a CPU labeled 30293E-003 20-04592-014. (c) On the PCB is a 20pin PCB-connector and according to my analysis this is a parallel port where the Dasher directly transmits ASCII. (d) Protocol and pinout: 1,2 : GND 3,4: +5V (approx 350-400mA). 5: /Strobe (a low-pulse of 1us signals that new data is valid on the parallel output lines D0-D7). Data is applied approx 5us before the strobe appears. 6: N.C. 7: D7, 8:D0, 9:D5, 10: D2, 11: D3, 12: D4, 13: D1, 14: D6, 15-17: N.C. 18-20: Outputs of still unkonwn purpose (originate from the 7437). Maybe related to the BREAK key - this is the only key which does not generate an ASCII-Code and a strobe pulse. Maybe this helps someone who wants to restore/debug/analyze/reuse one of these units... Best regards, Erik.