FPC-8057 User’s Manual
2.3.2 COM2 [RS-232] & COM3 [RS-422/485]
The 9 Pin, male, SUB-D, COM2 [RS-232] & COM3 [RS-422/485] Port
on the back of the unit is the downloading port (PC Connector) and RS-
485/422 communications port for connecting to a device .
Connector COM2 [RS-232] & COM3 [RS-2422/485]
Pin Designations
COM2 COM3 COM3
Pin# Symbol (RS-232) (RS-422) (RS-485)
1 GND GND GND GND
2 Tx+ RS-422 Transmit
3 Tx- RS-422 Transmit
4 Rx+ RS-422 Receive Data+
5 Rx- R S-422 Receive Data
6 GND
7 RxD Receive
8 TxD Transmit

9 Not used

16 Installation Instructions