Modbus – IAI America ROBO Cylinder Series User Manual
Page 90

5. Modbus RTU
82
Modbus
(4) Query sample
A sample query that reads the current position (address 9003
H
) of a controller with axis No. 0 is
shown below.
z
Query (silent intervals are inserted before and after the query)
01 03 90 03 00 01 59 0A
Field
RTU mode
8-bit data
Start
Silent interval
Slave address [H]
01
Function code [H]
03
Start address [H]
9003
Number of registers [H] 0001
Error check [H]
590A (in accordance with
CRC calculation)
End
Silent interval
The response to the query is as follows.
z
Response (silent intervals are inserted before and after the response)
01 03 02 90 00 D4 44
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]
90 00
Error check [H]
D444 (in accordance with CRC calculation)
End
Silent interval
The input data area address is “9000”
H
, o Convert into binary number
“1001000000000000.”
n
n
INT15 -------------------- INT 1
Note The data of the response example is simply an example and will vary depending on
various conditions.