Satec PM172 Series, Руководство владельца

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3 MODBUS MESSAGE FORMATS
3.1 Function 03 - Read Multiple Registers
This command allows the user to obtain contents of up to 125 contiguous registers from a single data table.
Request
Instrument
Address
Function
(03)
Starting
Address
Word Count Error Check
1 byte 1 byte 2 bytes 2 bytes 2 bytes
Starting Address Address of the first register to be read
Word Count The number of contiguous words to be read
Response
Instrument
Address
Function
(03)
Byte
Count
Data
Word 1
... Data
Word N
Error
Check
1 byte 1 byte 1 byte 2 bytes ... 2 bytes 2 bytes
The byte count field contains quantity of bytes to be returned.
3.2 Function 04 - Read Multiple Registers
This command allows the user to obtain contents of up to 125 contiguous registers from a single data table. It can
be used instead of function 03.
Request
Instrument
Address
Function
(04)
Starting
Address
Word Count Error Check
1 byte 1 byte 2 bytes 2 bytes 2 bytes
Starting Address Address of the first register to be read
Word Count The number of contiguous words to be read
Response
Instrument
Address
Function
(04)
Byte
Count
Data
Word 1
... Data
Word N
Error
Check
1 byte 1 byte 1 byte 2 bytes ... 2 bytes 2 bytes
The byte count field contains quantity of bytes to be returned.
3.3 Function 06 - Write Single Register
This command allows the user to write the contents of a data register in any data table where a register can be
written.
Request
Instrument
Address
Function
(06)
Starting
Address
Data
Word
Error check
1 byte 1 byte 2 bytes 2 bytes 2 bytes
Starting Address Address of the register to be written
Data Value Data to be written to the register
Response
The normal response is the retransmission of the write request.
3.4 Function 16 - Write Multiple Registers
This request allows the user to write the contents of multiple contiguous registers to a single data table where
registers can be written.