错误号与错误原因对照表:
0x01-“Illegal function”;
0x02-“Illegal data address”;
0x03-“Illegal data value”;
0x04-“Slave device or server failure”;
0x05-“Acknowledge”;
0x06-“Slave device or server is busy”;
0x07-“Negative acknowledge”;
0x08-“Memory parity error”;
0x09-“Not defined”;
0x0A-“Gateway path unavailable”;
0x0B-“Target device failed to respond”;
0x0C-“Invalid CRC”;
0x0D-“Invalid data”;
0x0E-“Invalid exception code”;
0x10-“Too many data”;
0x11-“Response not from requested slave”