2 Operation CJ2M-CPU3 □ Option Board Setting Switch ON DIP switch 5 to select Peripheral Bus (Toolbus) protocol. Grid Connect Modbus/TCP Adapter Application and Setup Guide 2-5 Switch No. Setting Description Application Default 5 ON Used for peripheral bus (Toolbus). Used to enable a Serial Communications Option Board mounted in Option Board Slot 1 to be used by the peripheral bus. OFF OFF According to PLC Setup.