program PID_Control;

// Variable declarations
var 
  Setpoint: real;  // Desired value 
  ProcessValue: real;  // Measured value
  Error: real;  // Difference between setpoint and process value 
  Integral: real;  // Accumulated error
  Derivative: real;  // Rate of change of error
  Output: real;  // Control signal
  Kp, Ki, Kd: real;  // PID gains 
  PreviousError: real;  // Error from previous iteration 

procedure CalculatePID;
begin
  Error := Setpoint - ProcessValue;  // Calculate error
  Integral := Integral + Error; // Update integral term 
  Derivative := (Error - PreviousError); // Calculate derivative 
  Output := Kp * Error + Ki * Integral + Kd * Derivative; // Calculate control signal
  PreviousError := Error;  // Update previous error for next iteration
end; 

begin
  // Initialize PID gains
  Kp := 1; 
  Ki := 0.1; 
  Kd := 0.01;

  // Main loop
  repeat 
    // Read process value (replace with actual sensor reading)
    ProcessValue := ... ; 

    // Calculate PID output
    CalculatePID; 

    // Apply control signal (replace with actuator control)
    ... 
  until false; 
end.