Instruction Manual

5. Modbus RTU
106
Modbus
(4) Query sample
A sample query that reads the special input port (address 9012
H
) of a controller of axis No. 0 is
shown below.
Query (silent intervals are inserted before and after the query)
01 03 90 12 00 01 09 0F
Field RTU mode
8-bit data
Start Silent interval
Slave address [H] 01
Function code [H] 03
Start address [H] 9012
Number of registers [H] 0001
Error check [H] 090F (in accordance with
CRC calculation)
End Silent interval
The response to the query is as follows.
Response (silent intervals are inserted before and after the response)
01 03 02 43 00 89 74
Field RTU mode
8-bit data
Start Silent interval
Slave address [H] 01
Function code [H] 03
Number of data bytes [H] 02 (2 bytes = 1 register)
Data 1 [H] 43 00
Error check [H]
8974 (in accordance with CRC calculation)
End Silent interval
Note The data of the response example is simply an example and will vary depending on
various conditions.