42 • Appendix C: USB Virtual COM Port for Modbus
AirLink 9850 Gas Monitor Operator’s Manual
Appendix C: USB Virtual COM Port for Modbus
The USB port on the AirLink 9850 outputs Modbus data in the register format outlined at
https://www.rkiinstruments.com/pdf/AirLink_9850-RegMap.pdf
The drivers for the AirLink 9850 automatically install when you connect the AirLink 9850 to a
Windows PC and turn the AirLink 9850 on. The AirLink 9850 appears as a “USB Serial Device” in the
device manager.
A computer program that reads Modbus, like Modbus Poll, can be used to poll the Modbus registers
and view information from the AirLink 9850.
