Delta DVP-15MC Series, Руководство по эксплуатации

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Appendix A. Modbus Communication
A-9
A_
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Example
To read the contents of address 16#0000 and 16#0001 in DVP-15MC series motion controller
via function code 03.
16#0000 and 16#0001 are the Modbus addresses of %MW0 and %MW1 in DVP-15MC series
motion controller respectively.
Suppose the value of %MW0 is 16#0001 and %MW1 is 16#0002:
Request message: 01 03 00 00 00 02 C4 0B
Response message: 01 03 04 00 01 00 02 2A 32

Function code 06 writes one single word register value

Data structure of a request message:
Byte NO. Name Byte
Byte0
Modbus ID Single byte
Byte1
Function code Single byte
Byte2
Controller’s register address where to write
the value
High byte
Byte3
Low byte
Byte4
The written value
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
Controller’s word register address where to
write the value
High byte
Byte3
Low byte
Byte4
The written value
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 an exception response message:
Byte NO. Name Byte
Byte0
Modbus ID Single byte
Byte1
16#80+ 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

Example
Write 16#0100 to the address 16#0000 in DVP-15MC series motion controller via function
code 06.
Request message: 01 06 00 00 01 00 88 5A
Response message: 01 06 00 00 01 00 88 5A