int ldrPin = A0;
int ledPin = 9;
int ldrValue = 0;
int threshold = 500;
void setup() {
pinMode(ledPin, OUTPUT);
Serial.begin(9600);
}
void loop() {
ldrValue = analogRead(ldrPin);
Serial.println(ldrValue);
if (ldrValue < threshold) {
digitalWrite(ledPin, HIGH);
} else {
digitalWrite(ledPin, LOW);
}
delay(100);
}
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// Reads LDR values and prints them to Serial Monitor
int ldrPin = A0; // LDR connected to analog pin A0
int ldrValue = 0; // Variable to store LDR value
void setup() {
Serial.begin(9600); // Start Serial communication
}
void loop() {
ldrValue = analogRead(ldrPin);
Serial.print("LDR Value: ");
Serial.println(ldrValue);
delay(1000); // Wait for 1 seconds
}
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// The press of button changes the pattern of LED glow
const int ledPins[] = {10, 11, 12, 13};
const int buttonPin = 7;
int currentPattern = 0;
int lastButtonState = 0; // For button state check
void setup() {
for (int i = 0; i < 4; i++) {
pinMode(ledPins[i], OUTPUT);
}
pinMode(buttonPin, INPUT);
}
void loop() {
int buttonState = digitalRead(buttonPin);
if (buttonState == HIGH && lastButtonState == LOW) {
currentPattern = (currentPattern + 1) % 4;
delay(300); // debounce
}
lastButtonState = buttonState;
runPattern(currentPattern);
}
void runPattern(int p) {
switch (p) {
case 0:
// Pattern 1: Forward running light
for (int i = 0; i < 4; i++) {
clearLEDs();
digitalWrite(ledPins[i], HIGH);
delay(150);
}
break;
case 1:
// Pattern 2: Forward + Backward running light
for (int i = 0; i < 4; i++) {
clearLEDs();
digitalWrite(ledPins[i], HIGH);
delay(150);
}
for (int i = 2; i >= 1; i--) {
clearLEDs();
digitalWrite(ledPins[i], HIGH);
delay(150);
}
break;
case 2:
// Pattern 3: Outside to Inside
clearLEDs();
digitalWrite(ledPins[0], HIGH);
digitalWrite(ledPins[3], HIGH);
delay(200);
clearLEDs();
digitalWrite(ledPins[1], HIGH);
digitalWrite(ledPins[2], HIGH);
delay(200);
break;
case 3:
// Pattern 4: Quick strobe effect
for (int j = 0; j < 10; j++) { // blink 10 times
setAllLEDs(HIGH);
delay(600);
setAllLEDs(LOW);
delay(600);
}
break;
}
}
void clearLEDs() {
for (int i = 0; i < 4; i++) {
digitalWrite(ledPins[i], LOW);
}
}
void setAllLEDs(int state) {
for (int i = 0; i < 4; i++) {
digitalWrite(ledPins[i], state);
}
}
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// LED Control using Increment and Decrement Buttons
const int ledPins[] = {10, 11, 12, 13};
const int plushBtn = 7;
const int minusBtn = 8;
int ledIndex = 0;
bool plushBtnState = HIGH;
bool minusBtnState = HIGH;
void setup() {
for (int i = 0; i < 4; i++) {
pinMode(ledPins[i], OUTPUT);
digitalWrite(ledPins[i], LOW);
}
pinMode(plushBtn, INPUT);
pinMode(minusBtn, INPUT);
}
void loop() {
bool currentInc = digitalRead(plushBtn);
bool currentDec = digitalRead(minusBtn);
// Increment button pressed
if (plushBtnState == HIGH && currentInc == LOW) {
if (ledIndex < 4) {
digitalWrite(ledPins[ledIndex], HIGH);
ledIndex++;
}
delay(200);
}
// Decrement button pressed
if (minusBtnState == HIGH && currentDec == LOW) {
if (ledIndex > 0) {
ledIndex--;
digitalWrite(ledPins[ledIndex], LOW);
}
delay(200);
}
plushBtnState = currentInc;
minusBtnState = currentDec;
}
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// Buzzer gives beep for 100ms and LED status is toggled
int ledState = LOW;
int buttonState = 0;
int lastButtonState = LOW;
void setup() {
pinMode(2, INPUT);
pinMode(12, OUTPUT);
pinMode(13, OUTPUT);
}
void loop() {
buttonState = digitalRead(2);
if (buttonState == HIGH && lastButtonState == LOW) {
ledState = !ledState;
digitalWrite(13, ledState);
digitalWrite(12, HIGH);
delay(100);
digitalWrite(12, LOW);
}
lastButtonState = buttonState;
delay(100);
}
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// LED blinks/glow when button is pressed
int buttonState = 0;
void setup() {
pinMode(2, INPUT);
pinMode(13, OUTPUT);
}
void loop() {
buttonState = digitalRead(2);
if (buttonState == HIGH) {
digitalWrite(13, HIGH);
} else {
digitalWrite(13, LOW);
}
delay(100);
}
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// LED and Buzzer is on and off delay of 1 sec
void setup() {
pinMode(13, OUTPUT);
pinMode(12, OUTPUT);
}
void loop() {
digitalWrite(13, HIGH);
digitalWrite(12, HIGH);
delay(1000);
digitalWrite(13, LOW);
digitalWrite(12, LOW);
delay(1000);
}
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// Buzz on/off with the delay of 1sec
void setup()
{
pinMode(13, OUTPUT);
}
void loop()
{
digitalWrite(13, HIGH);
delay(1000);
digitalWrite(13, LOW);
delay(1000);
}
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int leds[] = {10, 11, 12, 13};
// Each row represents a step in the pattern
int pattern[][4] = {
{1, 0, 0, 0},
{0, 1, 0, 0},
{0, 0, 1, 0},
{0, 0, 0, 1},
{1, 1, 0, 0},
{0, 1, 1, 0},
{0, 0, 1, 1}
};
int steps = sizeof(pattern) / sizeof(pattern[0]);
void setup() {
for (int i = 0; i < 4; i++) {
pinMode(leds[i], OUTPUT);
}
}
void loop() {
for (int i = 0; i < steps; i++) {
for (int j = 0; j < 4; j++) {
digitalWrite(leds[j], pattern[i][j]);
}
delay(3000);
}
}
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// Blinks 4 LEDs one-by-one
void setup() {
for (int i = 10; i <= 13; i++) {
pinMode(i, OUTPUT);
}
}
void loop() {
for (int i = 10; i <= 13; i++) {
// Turn OFF all LEDs
for (int j = 10; j <= 13; j++) {
digitalWrite(j, LOW);
}
// Turn ON current LED
digitalWrite(i, HIGH);
delay(1000);
}
}
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// LED Blink with 2 Second Delay
void setup() {
// Pin 13 ko output mode me set karna
pinMode(13, OUTPUT);
}
void loop() {
// LED ON karna
digitalWrite(13, HIGH);
delay(2000); // 2 second delay
// LED OFF karna
digitalWrite(13, LOW);
delay(2000); // 2 second delay
}
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