Topic 3. Arduino night lamp and button

Code allows you to toggle the LEDs on and off using a button while adjusting their brightness based on the light level sensed by the sensor. The autoTune() function ensures that the LED brightness adapts to varying light conditions efficiently.

Loop:

Reads the analog value from the sensor pin (pin 0), which presumably represents the light level.
Checks if the button (connected to pin 4) is pressed. If pressed, it toggles the ledState variable between true and false after a debounce delay of 200 milliseconds.
If ledState is true, it enters the block to control the LEDs:
- Calls the autoTune() function to adjust the lightLevel based on the low and high values.
- Sets the brightness of all three LEDs (ledPin1, ledPin2, ledPin3) using the adjusted lightLevel value.
If ledState is false, it turns off all three LEDs.

Arduino code

const int sensorPin = 0;
const int ledPin1 = 12;
const int ledPin2 = 11;
const int ledPin3 = 10;
const int buttonPin = 13; // Assuming the button is connected to digital pin 4

bool ledState = false; // Variable to track the state of LEDs
int low = 1023; // Initialize low and high values for autoTune()
int high = 0;

void setup() {
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP); // Enable internal pull-up resistor
  Serial.begin(9600); // Initialize serial communication
}

void loop() {
  int lightLevel = analogRead(sensorPin); // Read the analog value

  // Check if the button is pressed
  if (digitalRead(buttonPin) == LOW) {
    // If the button is pressed, toggle the LED state
    ledState = !ledState;
    delay(200); // Debouncing delay to prevent rapid toggling
  }

  if (ledState) {
    // If the LED state is true (ON), set the LEDs brightness based on light level
    autoTune(lightLevel); // Adjust lightLevel using autoTune()
    analogWrite(ledPin1, lightLevel);
    analogWrite(ledPin2, lightLevel);
    analogWrite(ledPin3, lightLevel);
  } else {
    // If the LED state is false (OFF), turn off the LEDs
    digitalWrite(ledPin1, LOW);
    digitalWrite(ledPin2, LOW);
    digitalWrite(ledPin3, LOW);
  }

  Serial.println(lightLevel); // Print the light level to serial monitor
  delay(1000); // Delay for stability
}

void autoTune(int &lightLevel) {
   if (lightLevel < low)  
  {                      
    low = lightLevel;   
  }
  if (lightLevel > high)
  {
    high = lightLevel;
  }
  lightLevel = map(lightLevel, low+10, high-30, 0, 255);
  lightLevel = constrain(lightLevel, 0, 255);
}