28 Nov
2013
28 Nov
'13
9:52 a.m.
If I recall correctly, the PDP-11 those 9-pin header
serial ports on
the '11 are able to do RS-422 and RS-423 on the DLV11-J; don't know
about on the MXV11 or KDF11-B.
They're almost all the same. All three have a differential receiver
pair, external clock line, and +12V on the same pins. On the DLV11-J,
the transmit is differential with pin 3 being TX+ and 4 being TX-. On
the MXV11 and KDF11-B, pin 4 is a ground, but of course feeding TX+
and GND into a differential receiver will work, so you still get
support for both RS-422 and RS-423 signaling.
BLS