Instruction FEND number main program ends FNC06, no operation, taking up 1 program step. FEND main program ends, as when performing to FEND, PLC input/output processing, watchdog timer, refresh, complete and return the start step.FEND instruction should be used note:
1) subroutines and interrupts service routines should be placed after the FEND;
2) subroutines and interrupts service routines must be written between FEND and END, or error.
PLC ONE 