Onboard MAX31865 supports selecting 2-wire or 4-wire of PT100/ PT1000. The difference between U2C V1.0 and U2C V2.1: U2C V1.0 has 1 CAN OUTPUT, U2C V2.1 has 3 CAN OUTPUT. With BOOT and RESET buttons reserved, users can update the firmware via DFU mode by USB.
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