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With FMC640 two external devices can be connected with RS232 to the device.
With FMC125 one RS232 or one RS485. Only one device can be used with FMC125
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Q: what is the command to get the odometer value?
A: FMB odoget
more information: https://wiki.teltonika-gps.com/view/FMB_odoget
https://wiki.teltonika-gps.com/view/FMB003_SMS/GPRS_Commands#Commands_Related_to_Features
Q: How to update his device with CAN-Control?
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