3. Instruction Set
Low byte to be force ON/OFF
Checksum: LRC CHK (0,1)
Registers for received data (responding messages)
D1072 low byte ‘0’ 30 H
Data Address
High byte to be force ON/OFF
Low byte to be force ON/OFF
RTU mode (M1143 = ON)
When X0 = ON, MODRW instruction executes the function specified by Function Code 05
PLC1 PLC2, PLC1 sends: “01 05 0500 FF00 8C F6”
PLC2 PLC1, PLC1 receives: “01 05 0500 FF00 8C F6”
Registers for data to be sent (sending messages)
Data Address
Data content (ON = FF00H)
Registers for received data (responding messages)
Data Address
Data content (ON = FF00H)