text: // the number of the motor pins
  const int gpioMotorA1 = 17;
  const int gpioMotorA2 = 2;
  const int gpioMotorAPwm = 15;
  const int gpioMotorB1 = 12;
  const int gpioMotorB2 = 13;
  const int gpioMotorBPwm = 27;
  
  // setting PWM properties
  const int pwmFreq = 20000;
  const int motorRPwmChannel = 0;
  const int motorLPwmChannel = 1;
  const int pwmResolution = 8; //bits
  
  // TTGO Display buttons
  const int gpioSelectButton = 35;
  const int gpioEnterButton = 0;
  
  // Connected Servos
  const int gpioSteeringServo = 26;
  const int steeringServoCentre = 105; // Nominally 100 = mid range of movement (bigger = steer more left)
  const int steeringServoFreq = 300;  // Servo refresh rate (50Hz to about 300Hz for most digial servos)
  
  // Sensors
  const int gpioSensorStartFinish = A5; // Rightmost sensor
  const int gpioSensorRightLine = A4;
  const int gpioSensorLeftLine = A3;
  const int gpioSensorRadius = A0;  // Leftmost sensor
  
  // LEDs
  const int gpioIlluminationLED = 25;
  
  // PID values
  const float LOOP_INTERVAL = 0.003;  // 1mS
  const float LOOP_FREQUENCY = 1/LOOP_INTERVAL;  // Hz
  const float MAX_MOTOR_VOLTS = 100.0;
  const float PID_Kp = 0.005;// 0.007;
  const float PID_Ki = 0.0;
  const float PID_Kd = 0.001;
  