E m b e d d e d C o n t r o l l e r A E C - 6 8 6 0Chapter 2 Hardware Installation 2 - 42.3 COM2 RS-232/422/485 Serial Port ConnectorDifferent devices implement the RS-232/422/485 standard indifferent ways. If you are having problems with a serial device, besure to check the pin assignments below for the connector.Pin Signal Pin Signal1 DCD (422TXD-/485DATA-) 2 RXD (422RXD+)3 TXD (422TXD+/485DATA+) 4 DTR (422RXD-)5 GND 6 DSR7 RTS 8 CTS9 RI 10 N.C.2.4 COM1 RS-232 Serial Port ConnectorPin Signal Pin Signal1 DCD 2 RXD3 TXD 4 DTR5 GND 6 DSR7 RTS 8 CTS9 RI 10 N.C.