47Example of analysis for packet receivedData received (hexadecimal)10H 02h 00h 13h 00h 00h 31h 32h 33h 34h 35h 36h 37h 38h 0Dh C4h 18h 10h 03h(1) Compare data lengths.Data length received in packet: 0013h = 19 bytesData received in packet: 19 bytes(2) Compare CRCs.1) Initialize CRC to 0.2) Retrieve the first data byte (00h).3) Shift the current CRC value one bit to the left. If the shift produces overflow, XOR the result with 1021h.4) Shift the data byte one bit to the left. If the shift produces overflow, XOR the current CRC value with 0001h.5) Repeat steps 3) and 4) a total of 8 times.6) Retrieve the second data byte (13h).7) Repeat steps 3) and 4) a total of 8 times.8) Repeat this calculation through to the final byte.9) Finally repeat the calculation for the two bytes (C4h 18h) in the CRC storage area, but reverse them firstbecause the 16-bit CRC is stored in little-endian order.Data CRC-- 0000h00h 0000h13h 1300h00h 0013h00h 221Ah31h 8EF9h32h 58C0h33h F554h34h 2054h35h 2181h36h A3A0h37h 92A9h38h 0059h0Dh C244h18h 1CE2hC4h 0000h(3) A result of 0000h indicates a successful transfer; a nonzero one, an error.Transfer dataSpareNumber ofdata bytesCRCHeader Terminator
