Instruction Manual

6. Modbus ASCII
218
Modbus
(4) Sample query
A sample query that reads the expansion device status (address 9007
H
) in a controller of axis No. 0
is shown below.
Query: 01 03 90 07 00 01 64 [CR] [LF]
Field ASCII mode
fixed character string
Converted ASCII
code data [H]
Start ‘:’ 3A
Slave address [H] ‘0’, ‘1’ 3031
Function code [H] ‘0’, ‘3’ 3033
Start address [H] ‘9’, ‘0’, ‘0’, ‘7’ 39303037
Number of registers [H] ‘0’, ‘0’, ‘0’, ‘1’ 30303031
Error check [H] ‘6’, ‘4’ (In accordance with LRC calculation) 3634
End ‘CR’, ‘LF’ 0D0A
The response to the query is as follows.
Response: 01 03 02 33 C7 00 [CR] [LF]
Field ASCII mode
fixed character string
Converted ASCII
code data [H]
Start ‘:’ 3A
Slave address [H] ‘0’, ‘1’ 3031
Function code [H] ‘0’, ‘3’ 3033
Number of data bytes [H] ‘0’, ‘2’ (2 bytes = 1 register) 3032
Data 1 [H] ‘3’, ‘3’, ‘C’, ‘7’ 33334337
Error check [H] ‘0’, ‘0’ (In accordance with LRC calculation) 3030
End ‘CR’, ‘LF’ 0D0A
Note The data of the response example is simply an example and will vary depending on
various conditions.