19 Sep
2003
19 Sep
'03
1:49 a.m.
Ed wrote:
Not likely in this case, 2 of the wires must carry the power, as there is no
own powersource in the terminal. I picked it up when collecting 4 11/34's at Shell,
and in one of the cupboard I found this pocket terminal.
I have opened the db25 plug, and pins 2 & 3 are wired, suggesting it is at least
RS232.
Other pins are 4 (RTS, wired also to pin 20), pin 7 (GND) and pin 9 (+ voltage).
The pin assignment is according to the rs232 description.
There is an N8T15 & N8T16 chip on the board, are these similar to the M1488 &
M1489
rs232 line driver chips?
... found listings in an IC Master (1982) (sorry no pinouts):
N8T15 (Signetics): Line drivers, single-ended (2 per device)
/ 4-input; RS232B,C; MIL188 / Output +-6V / Power Supply +-12V
N8T16 (Signetics): Line receivers (2 per device)
/ hysteresis EIA/MIL / Input Threshold +-2V / Supply Voltage 5V