Specifications

Pinouts and Cable Wiring l l Appendix A

A.3 RS-485

The pinouts of the RS-485 port are the same as RS-422 except that only TxD+,

TxD-, RxD+, RxD- and GND are used. The following lists pinouts of the RS-422

port.

C114HI DB-9 Male Connector C114HI Pin-head Connector

1 TxD-(A) 1 TxD-(A)

2 RxD+(B) 2 RxD+(B)

3 TxD+(B) 3 TxD+(B)

4 RxD-(A) 4 RxD-(A)

5 GND 5 GND

There are two operation modes for RS-485. Note that when jumper set to half

duplex, TxD+ with RxD+ and TxD- with RxD- are shorted internally on board.

Only TxD+ and TxD- are good for connection.

1. Point-to-Point

Point-to-Point configuration means two devices located at two different places

can be linked together to communicate via RS-485 interface.

Point-to-Point RS-485 Half-Duplex Point-to-Point RS-485 Full-Duplex

C114HI Remote site C114HI Remote site

1 TxD- RxD- 1 TxD- RxD-

4 RxD- TxD- 4 RxD- TxD-

3 TxD+ RxD+ 3 TxD+ RxD+

2 RxD+ TxD+ 2 RxD+ TxD+

5 GND GND 5 GND GND

GND

RxD-

TxD+

RxD+

TxD-