Jeff you made me google a MMJ
DEC MMJ
MMJ=Modified Modular Jack
Invented by Digital Equipment Corporation (DEC) (now: Compaq)
(at the devices)
(at the cables)
MMJ FEMALE CONNECTOR at the devices.
MMJ MALE CONNECTOR at the cables.
Pin Name Description
1 DTR Data Terminal Ready
2 TXD+ Transmit Data +
3 TXD- Transmit Data -
4 RXD+ Receive Data +
5 RXD- Receive Data -
6 DSR Data Set Ready
Jeff