In-Situ Aqua TROLL 400 Modbus and SDI-12 Reference Guide - Manual (Page 11)

DB-9 Pin Diagram
Pin Signal Name
1 Carrier Detector DCD
2 Receive Data RXD
3 Transmit Data TXD
4 Data Terminal Ready DTR
5 Signal Ground/Common GND
6 Data Set Ready DSR
7 Request to Send RTS
8 Clear to Send CTS
9 Ring Indicator RI
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