计算CRC校验和,可以计算modbus规约/CDT规约/DISA规约/DF1规约/DNP规约/1801等规约的校验和.-and CRC calculation, modbus connection can be calculated Statute / CDT Statute / DISA Statute / DF1 Statute / DNP Statute / 18 01 of the Statute, such as checksum.