COMPxELEC_TeleCommunication Let's gooooo! Packing and Unpacking notes: The checksum is using CRC16. https://crccalc.com/?crc=123456789&method=&datatype=ascii&outtype=hex The checksum is represented as big endian. The starting key for every packet is b'\x1A\xCF'. (0x1ACF)