Quatech Connector Pinout: DB-37 connector: RS-232

Signal

Port 1

Port 2

Port 3

Port 4

TxD

Pin 24

Pin 10

Pin 33

Pin 19

RxD

Pin 5

Pin 28

Pin 14

Pin 37

RTS

Pin 23

Pin 10

Pin 33

Pin 18

CTS

Pin 4

Pin 27

Pin 13

Pin 36

DTR

Pin 21

Pin 7

Pin 30

Pin 16

DSR

Pin 22

Pin 8

Pin 31

Pin 18

DCD

Pin 2

Pin 25

Pin 11

Pin 34

RI

Pin 20

Pin 6

Pin 29

Pin 15

Ground

Pin 3

Pin 26

Pin 12

Pin 35