7. Connection Procedure 7.4.2. Checking Data that are Sent and Received Confirm that correct data are sent and received. Confirm safety sufficiently before monitoring power flow and present value status in the Ladder Section window or before monitoring present values in the Watch window. If force-set/reset or set/reset operations are incorrectly performed by pressing short-cut keys, the devices connected to Output Units may malfunction, regardless of the operating mode of the CPU Unit. 26 1 Confirm that the PLC is in PROGRAM mode. *If the PLC is not in the PROGRAM mode, change to PROGRAM mode by referring to step 1 of 7.3.3. Creating the I/O Table. 2 Select Edit - Memory from the PLC Menu.