Do the RM024, LT1110 modules already perform some sort of CRC or checksum into the packets being transferred? If so how many bytes are used for the CRC?

Answer

 Do the RM024, LT1110 modules already perform some sort of CRC or checksum into the packets being transferred? If so how many bytes are used for the CRC? Yes, both the RM024 and LT1110 (as well as the EOL LT2510) radios run a CRC on the received packets. If the CRC fails the packet is discarded and retries are used. The modules have a 16-bit CRC which is automatically calculated across the entire payload. What we found in testing was that 16 bits was not enough, as we were able to induce errors on the RF that passed the 16-bit CRC check, and was allowing packets through containing errors. Therefore, we added an 8-bit checksum in addition to the 16-bit CRC. This effectively gives 24-bits, and we have not been able to induce an error that was not caught by the 16-bit CRC + 8-bit checksum. We hope this helps.