Delta Electronics DVP15MC11T, Руководство по эксплуатации

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DVP15MC11T Operation Manual
A
A.5 Introduction to Modbus Function Codes

Function code 03 reads one single or multi word register values

Data structure of a request message:
Byte NO. Name Byte
Byte0
Modbus ID Single byte
Byte1
Function code Single byte
Byte2
Read the start address of word registers in
DVP15MC11T
High byte
Byte3
Low byte
Byte4
Read the number of addresses of word registers
in DVP15MC11T
(Counted by Word)
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 addresses of word registers
in DVP15MC11T
(Counted by Byte)
Single byte
Byte3
The address content of the word register in
DVP15MC11T
High byte
Byte4
Low byte
…
The address content of the word register in
DVP15MC11T
High byte
… Low byte
Byte n
The address content of the word register in
DVP15MC11T
High byte
Byte n+1
Low byte
Byte n+2
Low byte of CRC check sum Low byte
Byte n+3 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 code Single byte
Byte3
Low byte of CRC check sum Low byte
Byte4
High byte of CRC check sum High byte
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