Delta Electronics DVP15MC11T, Руководство по эксплуатации

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Appendix A. Modbus Communication
A_

Example
Write 0x0100 and 0x0200 to the addresses 0x0000 and 0x0001 in DVP15MC11T respectively
via function code 0x10. 0x0000 and 0x0001 are Modbus addresses of %MW0 and %MW1 in
DVP15MC11T respectively.
Request message: 01 10 00 00 00 02 04 01 00 02 00 F3 33
Response message: 01 10 00 00 00 02 41 C8

Function code 0x01 reads multiple output bit register values

Data structure of a request message:
Byte NO. Name Byte
Byte0
Modbus ID Single byte
Byte1
Function code Single byte
Byte2
The start address of DVP15MC11T bit registers to
be read
High byte
Byte3 Low byte
Byte4
The number of DVP15MC11T bit registers to be
read
High byte
Byte5 Low byte
Byte6
Low byte of CRC check sum Low byte
Byte7
High byte of CRC check sum High byte

Data structure of a response message:
Byte NO. Name Byte
Byte0
Modbus ID Single byte
Byte1
Function code Single byte
Byte2 Read the number of bytes of bit registers.
Single byte
Byte3 Read the state value of the bit register.
Single byte
… Read the state value of the bit register.
Single byte
Byte n Read the state value of the bit register.
Single byte
Byte n+1
Low byte of CRC check sum Low byte
Byte n+2
High byte of CRC check sum High byte

Data structure of an exception response message:
Byte NO. Name Byte
Byte0
Modbus ID
Single byte
Byte1
0x80+ function code Single byte
Byte2
Exception response message Single byte
Byte3
Low byte of CRC check sum Low byte
Byte4
High byte of CRC check sum
High byte
Note:
The value of Byte 2 in the response message is determined by the values of Byte 4 and Byte 5
in the request message. For example, the number of the read bit registers in the request
A-11