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A: Dual Cam is connected to FMXXX via RS232
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Q: Which firmware to use for Dualcam?
A: DualCam firmware version 03.00.14.Rev.112 for FMC650 is available from here: https://wiki.teltonika-gps.com/view/DualCam_Firmware_errata
As well, instructions on how to properly configure your DualCam is available from here: https://wiki.teltonika-gps.com/view/DualCam_Configuration#FMC650_DualCam_Configuration