Return Query Data (Sub-Function Code: 00H) - Mitsubishi Electric MELSEC iQ-R Series Reference Manual

Return query data (sub-function code: 00H)

Operation description
Returns the contents of the request message without change.
Used to check if the network or the target device is operating normally. (Loopback test)
Request message format (from master to slave)
Function code Sub-function code
08H
(H)
Response message format (from slave to master)
■ When completed successfully
The slave returns the request message received from the master as-is.
■ When completed with an error
Function code Data
Exception code
88H
3 MODBUS STANDARD FUNCTION DETAILS
22
3.8 Diagnostics (FC: 08H)
(0000H)
(L)
Data
Arbitrary data