HNC Electric HV480 Series, Руководство пользователя

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Function example
Function 0x03: read n register words, read range 1 ~ 16
The slave address is 01h, and two consecutive data words are read first. The starting address is F000H of the
communication parameter register. The structure of the frame is described as follows:
Message start 3.5 bytes of transmission time
Slave address 0 1H
Modbus function code 0 3H
Starting address high byte F 0H
Starting address low byte 0 0H
High byte of data 0 0H
Low byte of data 0 2H
CRC low byte F 7H
CRC high byte 0 BH
End of message 3.5 bytes of transmission time
Function instruction 0x03 requests frame
Message start 3.5 bytes of transmission time
Slave address 0 1H
Modbus function code 0 3H
High number of data bytes 0 0H
Low number of data bytes 0 4H
Register F000H data high byte 0 0H
Register F000H data high byte 0 BH
Register F000H data high byte 0 0H
Register F000H data high byte 0 0H
CRC low byte
CRC high byte
End of message 3.5 bytes of transmission time
Function instruction 0x03 slave responds to frame
Function 0x06: modify a register word.
Note: frequent write operations can damage internal memory!
①
Execute the write command, and the data will be written into the internal register. The memory has a limit on
the number of write operations. If the limit is exceeded, the memory address will be destroyed. Please avoid frequent
write operations.
② If it is necessary to write to an address frequently, it is recommended to use function instruction 0x05.