Interface is based on RS-422 specifications.
| Pin Number |
Pin |
Pin Name (slave) |
|---|---|---|
| 1 | Frame ground | Frame ground |
| 2 | Receive A | Transmit A |
| 3 | Transmit B | Receive B |
| 4 | Transmit common | Receive common |
| 5 | Spare or ground | Spare or ground |
| 6 | Receive common | Transmit common |
| 7 | Receive B | Transmit B |
| 8 | Transmit A | Receive A |
| 9 | Frame ground | Frame ground |
Pins 2 and 7 form a pair and must be twisted together on long runs.
Pins 3 and 8 form a pair and must be twisted together on long runs.

