Omega Engineering RS-422/485 Connector Pin Assignments DB-9 Pin Assignments, Signal, Name, Pin #

Technical Description

Connector Pin Assignments

DB-9 Pin Assignments

Signal	Name	Pin #	Mode
GND	Ground	5
TX +	Transmit Data Positive	4	Output
TX-	Transmit Data Negative	3	Output
RTS+	Request To Send Positive	6	Output
RTS-	Request To Send Negative	7	Output
RX+	Receive Data Positive	1	Input
RX-	Receive Data Negative	2	Input
CTS+	Clear To Send Positive	9	Input
CTS-	Clear To Send Negative	8	Input

DB-37 Connector Pin Assignments

Port #	1	2	3	4
GND	33	14	24	5
TX-	35	12	26	3
RTS-	17	30	8	21
TX+	34	13	25	4
RX-	36	11	27	2
CTS-	16	31	7	22
RTS+	18	29	9	20
RX+	37	10	28	1
CTS+	15	32	6	23

OMG-ULTRA-COMM422 Page 17