(* Sorting conveyor. *)
(* Start and Stop run the belt, with a seal-in. Parts arrive on their own. At the pusher station a photo-eye sees every part and an inductive sensor sees only metal ones: push the metal parts into the reject bin and let the plastic parts ride to the end. Ten in a row with no mistakes passes. *)

VAR_GLOBAL
  Start_PB     AT %IX0.0  : BOOL; (* Start pushbutton, normally open *)
  Stop_PB      AT %IX0.1  : BOOL; (* Stop pushbutton, normally closed, 1 when healthy *)
  PE_Entry     AT %IX0.2  : BOOL; (* Photo-eye at the feeder, 1 when a part is there *)
  PE_Pusher    AT %IX0.3  : BOOL; (* Photo-eye at the pusher station, sees every part *)
  Metal_Sensor AT %IX0.4  : BOOL; (* Inductive sensor at the pusher station, sees metal parts only *)
  Belt         AT %QX0.0  : BOOL; (* Conveyor motor contactor *)
  Pusher       AT %QX0.1  : BOOL; (* Reject pusher solenoid valve, 1 extends *)
END_VAR

PROGRAM Main
  (* Write the logic here. *)
END_PROGRAM