MITSUBISHI ELECTRIC T-60 - Manual (Page 95)

The Omron status write must be performed in the following manner:
CALL PLCWRITE(0,1,0,1,mode)
mode: 0 - program
1 - debug
2 - monitor
3 - run
The Omron PLC must be in the monitor mode to enable write commands to
perform without errors. A CALL PLCINIT( id, 1) places the PLC into the
monitor mode, but if your application has a programming panel or some other
peripheral device attached, it may be possible for the operator to disable
writes to the PLC. Use the status write function to return the PLC to the
monitor mode when necessary.
PLC Interface Commands PLC Specific Information
87