7-7
Chapter 7. Modbus RTU Communication Functions
z
Multiple data write command (10H)
Writes continuous data addresses in hexadecimal notation.
z
z
Instruction message
Specifies the start address and the amount of data and 1 or more data items. The
structure of the instruction message is as follows.
Example: The values at addresses 01A0H and 0E53H are written to two continuous
data addresses starting at 05DDH.
(1) Station address
(2) Function code
(3) Write start data address
(4) Number of write data
(5) Number of write data × 2
(6) Write data 1
(7) Write data 2
(8) Check code (CRC)
z
z
Response message
The structure of the response message is as follows.
(1) Station address
(2) Function code
(3) Write start data address
(4) Number of write data
(5) Check code (CRC)
Note
•
The response message in case of an error is the same as the multiple data read
command in case of an error.
z
1 data write command (06H)
Writes data only with one data address in hexadecimal notation.
z
z
Original message
Specifies the data address and data. The structure of the instruction message is as
follows.
Example: The value of 01A0H is written to the data address of 05DDH.
(3)
(4)
01H
(1)
10H
(2)
05H
00H 02H 04H
(5)
01H A0H 0EH 53H 45H B9H
(6)
(7)
(8)
DDH
(2)
(1)
(3)
(4)
01H 10H 05H DDH 00H 02H D1H
(5)
3EH
(2)
(1)
(3)
(4)
01H 06H 05H DDH 01H A0H 18H
(5)
D4H
