18
3 MODBUS STANDARD FUNCTION DETAILS
3.5 Write Single Coil (FC: 05H)
3.5 Write Single Coil (FC: 05H)
Operation description
Writes a value (ON/OFF) to one coil.
Request message format (from master to slave)
Response message format (from slave to master)
â– When completed successfully
The slave returns the request message received from the master as-is.
â– When completed with an error
(H) (L) (H) (L)
05H
FF00H: ON
0000H: OFF
Coil number specification
Data
ON/OFF specification
Function code
(0000H to FFFFH)
85H
Data
Exception code
Function code