4-4 Communication Function CRC-16 Calculation Example CRC-16 calculation CRC *1 CRC = FFFFh CRC register (2 bytes) Target data Exists CRC = CRC XOR target data All target data completed 8-bit shift Completed 4 Bits left Interchange the Hi and Lo bytes of CRC Shift CRC = CRC by 1 bit to the right Functions 0 Overflow bit after shift 1 Completed CRC = CRC XOR A001h Shift by 1 byte against target data •Wait time from receiving the query from the master to the response by the Inverter. •Be sure to provide 3.5 characters (24 bits) as the wait time. If the length does not reach 3.5 characters, the Inverter does not respond.
•The actual communication wait time is the total of the silent interval (3.5-character length) and C078 (communication wait time) setting. Message Configuration: Response •The time from receiving query to the response by the Inverter is the total of the silent interval (3.5- character length) and C078 (communication wait time) setting. •If sending another query to the Inverter after receiving the response, be sure to provide the silent interval length (3.5 characters) at the minimum. •If the query is the loop-back function code (08h), the Inverter sends back a response of the same content as the query.
•If the query is the function code to be written into the holding register or coil (05h, 06h, 0Fh, 10h), the Inverter sends back the query as it is in response. •If the query is the function code to be read from the holding register or coil (01h, 03h), the Inverter makes the slave address and function code the same as the query and attaches the read data to the query. 4-156 Hi Lo