Zet Structured Text om in heldere diagrammen

PROGRAM PRG_TrafficLight
VAR
    xEnable        : BOOL;        // Master enable for the intersection
    xPedestrian    : BOOL;        // Pedestrian request button
    iStep          : INT := 0;    // State machine step

    xRed           : BOOL;        // Red lamp output
    xYellow        : BOOL;        // Yellow lamp output
    xGreen         : BOOL;        // Green lamp output
    xWalk          : BOOL;        // Pedestrian "walk" lamp

    fbStepTimer    : TON;         // Phase timer
END_VAR

CASE iStep OF

    0: // RED
        xRed    := TRUE;
        xYellow := FALSE;
        xGreen  := FALSE;
        xWalk   := FALSE;
        fbStepTimer(IN := TRUE, PT := T#5s);
        IF xEnable AND fbStepTimer.Q THEN
            fbStepTimer(IN := FALSE);
            iStep := 10; // Go to green
        END_IF;

    10: // GREEN
        xRed    := FALSE;
        xGreen  := TRUE;
        fbStepTimer(IN := TRUE, PT := T#8s);
        IF fbStepTimer.Q THEN
            fbStepTimer(IN := FALSE);
            iStep := 20; // Time to clear the intersection
        END_IF;

    20: // YELLOW
        xGreen  := FALSE;
        xYellow := TRUE;
        fbStepTimer(IN := TRUE, PT := T#3s);
        IF fbStepTimer.Q THEN
            fbStepTimer(IN := FALSE);
            IF xPedestrian THEN
                iStep := 30; // Serve waiting pedestrians
            ELSE
                iStep := 0;  // Back to red
            END_IF;
        END_IF;

    30: // WALK
        xRed    := TRUE;
        xYellow := FALSE;
        xWalk   := TRUE;
        fbStepTimer(IN := TRUE, PT := T#6s);
        IF fbStepTimer.Q THEN
            fbStepTimer(IN := FALSE);
            xWalk := FALSE;
            iStep := 0; // Back to red
        END_IF;

END_CASE;

PROGRAM PLC_PRG
VAR
    // System Control Inputs
    xStartKnop          : BOOL;    // Starts the batch process
    xStopKnop           : BOOL;    // Pauses the process safely
    xNoodstop           : BOOL;    // Emergency Stop (Active LOW)
    xResetKnop          : BOOL;    // Resets faults

    // Process Feedback Sensors
    rActueelGewicht     : REAL;    // Current tank weight from load cells [kg]
    rDoelGewicht        : REAL := 500.0; // Target weight for raw material [kg]
    xNiveauHoog         : BOOL;    // High level switch sensor (safety backup)
    xNiveauLaag         : BOOL;    // Low level switch sensor (tank empty indicator)

    // Actuator Outputs
    xVulVentiel         : BOOL;    // Control valve for filling raw material
    xMengMotor          : BOOL;    // Motor control for the tank mixer
    xAfvoerVentiel      : BOOL;    // Control valve for discharging final product

    // Internal State Machine Variables
    diStap              : DINT := 0;  // Current step indicator for state machine
    diVorigeStap        : DINT := -1; // Tracking for ENTRY logic execution
    xFoutActief         : BOOL;    // System fault flag
    sStatusMelding      : STRING;  // Human-readable status message

    // Process Timers
    fbMengTimer         : TON;     // Timer for the mixing duration
    fbVulTimeout        : TON;     // Safety timeout if filling takes too long
END_VAR

// =============================================================================
// GLOBAL SAFETY INTERLOCKS (Executed every cycle)
// =============================================================================
IF NOT xNoodstop THEN
    diStap := 100; // Immediate jump to Emergency Stop State
END_IF;

// =============================================================================
// MAIN STATE MACHINE
// =============================================================================
CASE diStap OF

    0: // IDLE STATE 
        sStatusMelding := "0 - System Idle. Awaiting Start.";
        xVulVentiel    := FALSE;
        xMengMotor     := FALSE;
        xAfvoerVentiel := FALSE;

        // Transition Condition
        IF xStartKnop AND NOT xStopKnop AND NOT xFoutActief THEN
            diStap := 10; // Proceed to Initialization
        END_IF;


    10: //  INITIALIZATION 
        sStatusMelding := "10 - Initializing Process and Verifying Sensors.";
        
        // Reset process timers
        fbMengTimer(IN := FALSE);
        fbVulTimeout(IN := FALSE);

        // Transition Condition (Verify tank is ready and empty)
        IF NOT xNiveauHoog THEN
            diStap := 20; // Proceed to Filling
        ELSE
            xFoutActief := TRUE;
            diStap := 90; // High level fault on startup
        END_IF;


    20: //  FILLING RAW MATERIAL 
        sStatusMelding := "20 - Filling Valve Open. Dosing Material.";
        xVulVentiel    := TRUE;

        // Run safety filling timeout
        fbVulTimeout(IN := TRUE, PT := T#45s);

        // Transition Conditions
        IF rActueelGewicht >= rDoelGewicht THEN
            xVulVentiel := FALSE;
            diStap      := 30; // Weight reached, go to Mixing
        ELSIF fbVulTimeout.Q OR xNiveauHoog THEN
            xVulVentiel := FALSE;
            xFoutActief := TRUE;
            diStap      := 91; // Timeout or Overflow Fault
        ELSIF xStopKnop THEN
            xVulVentiel := FALSE;
            diStap      := 50; // Pause requested
        END_IF;


    30: // MIXING PROCESS 
        sStatusMelding := "30 - Mixing Agitator Running.";
        xMengMotor     := TRUE;

        // Run mixing timer (e.g., 15 seconds)
        fbMengTimer(IN := TRUE, PT := T#15s);

        // Transition Conditions
        IF fbMengTimer.Q THEN
            xMengMotor := FALSE;
            diStap     := 40; // Mixing done, go to Discharge
        ELSIF xStopKnop THEN
            xMengMotor := FALSE;
            diStap     := 50; // Pause requested
        END_IF;


    40: //  DISCHARGING TANK 
        sStatusMelding := "40 - Discharge Valve Open. Emptying Tank.";
        xAfvoerVentiel := TRUE;

        // Transition Conditions
        IF NOT xNiveauLaag AND rActueelGewicht <= 5.0 THEN
            xAfvoerVentiel := FALSE;
            diStap         := 0; // Tank is empty, return to Idle
        ELSIF xStopKnop THEN
            xAfvoerVentiel := FALSE;
            diStap         := 50; // Pause requested
        END_IF;


    50: // PAUSE STATE 
        sStatusMelding := "50 - Process Paused by Operator.";
        // Keep all actuators safely off during pause
        xVulVentiel    := FALSE;
        xMengMotor     := FALSE;
        xAfvoerVentiel := FALSE;

        // Transition Condition (Resume or Abort)
        IF xStartKnop AND NOT xStopKnop THEN
            // Retain timers and jump back to previous execution state
            IF rActueelGewicht < rDoelGewicht THEN
                diStap := 20; // Resume Filling
            ELSE
                diStap := 30; // Resume Mixing
            END_IF;
        END_IF;


    90: // FAULT: STARTUP HIGH LEVEL OVERFLOW 
        sStatusMelding := "90 - CRITICAL FAULT: Tank high level on startup.";
        IF xResetKnop THEN
            xFoutActief := FALSE;
            diStap      := 0;
        END_IF;


    91: // FAULT: FILLING TIMEOUT / OVERFLOW 
        sStatusMelding := "91 - CRITICAL FAULT: Filling timeout or sensor high active.";
        IF xResetKnop AND NOT xNiveauHoog THEN
            xFoutActief := FALSE;
            diStap      := 10; // Re-initialize
        END_IF;


    100: //  EMERGENCY STOP ACTIVE 
        sStatusMelding := "100 - EMERGENCY STOP ACTIVE. Hard shutdown.";
        xVulVentiel    := FALSE;
        xMengMotor     := FALSE;
        xAfvoerVentiel := FALSE;

        // Transition Condition (Only allow escape if hardware E-stop is physically cleared)
        IF xNoodstop AND xResetKnop THEN
            diStap := 0; // Return to Idle safely
        END_IF;

ELSE
    // Catch-all safety for undefined states
    diStap := 100;
END_CASE;

// =============================================================================
// TIMER FUNCTION BLOCK CALLS (Executed every cycle)
// =============================================================================
fbMengTimer();
fbVulTimeout();

PROGRAM PRG_ConveyorSorter
VAR
    xStart         : BOOL;        // Start / run request
    xPartPresent   : BOOL;        // Photo-eye: part on the belt
    xScanDone      : BOOL;        // Vision scan finished
    xIsReject      : BOOL;        // Scan result: bad part
    xDiverted      : BOOL;        // Pusher reached end position
    xFault         : BOOL;        // Any drive / sensor fault
    xReset         : BOOL;        // Operator reset

    xBelt          : BOOL;        // Belt motor output
    xPusher        : BOOL;        // Divert pusher output
    iStep          : INT := 0;    // State machine step

    fbScan         : TON;         // Vision scan dwell timer
END_VAR

IF xFault THEN
    iStep := 90; // Jump to fault from any state
END_IF;

CASE iStep OF

    0: // IDLE
        xBelt   := FALSE;
        xPusher := FALSE;
        IF xStart AND xPartPresent THEN
            iStep := 10; // Part detected, start transporting
        END_IF;

    10: // TRANSPORT
        xBelt := TRUE;
        fbScan(IN := TRUE, PT := T#1s);
        IF fbScan.Q THEN
            fbScan(IN := FALSE);
            iStep := 20; // Hold under the scanner
        END_IF;

    20: // SCAN
        xBelt := FALSE;
        IF xScanDone THEN
            IF xIsReject THEN
                iStep := 40; // Bad part, push to reject lane
            ELSE
                iStep := 30; // Good part, pass through
            END_IF;
        END_IF;

    30: // ACCEPT
        xBelt := TRUE;
        IF NOT xPartPresent THEN
            iStep := 0; // Part has left the belt
        END_IF;

    40: // DIVERT
        xBelt   := FALSE;
        xPusher := TRUE;
        IF xDiverted THEN
            xPusher := FALSE;
            iStep := 0; // Reject pushed off, back to idle
        END_IF;

    90: // FAULT
        xBelt   := FALSE;
        xPusher := FALSE;
        IF xReset THEN
            iStep := 0; // Cleared, back to idle
        END_IF;

END_CASE;