Arduino - Button - LED
We are going to learn how to:
- Turn on LED if button is pressing.
- Turn off LED if button is NOT pressing.
We will learn how to toggle LED each time button is pressed in Arduino - Button Toggles LED tutorial.
Hardware Required
Or you can buy the following sensor kits:
1 | × | DIYables Sensor Kit (30 sensors/displays) | |
1 | × | DIYables Sensor Kit (18 sensors/displays) |
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Additionally, some links direct to products from our own brand, DIYables.
Additionally, some links direct to products from our own brand, DIYables.
Wiring Diagram
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Arduino Code
/*
* Created by ArduinoGetStarted.com
*
* This example code is in the public domain
*
* Tutorial page: https://arduinogetstarted.com/tutorials/arduino-button-led
*/
// constants won't change. They're used here to set pin numbers:
const int BUTTON_PIN = 7; // the number of the pushbutton pin
const int LED_PIN = 3; // the number of the LED pin
// variables will change:
int buttonState = 0; // variable for reading the pushbutton status
void setup() {
// initialize the LED pin as an output:
pinMode(LED_PIN, OUTPUT);
// initialize the pushbutton pin as an pull-up input:
// the pull-up input pin will be HIGH when the switch is open and LOW when the switch is closed.
pinMode(BUTTON_PIN, INPUT_PULLUP);
}
void loop() {
// read the state of the pushbutton value:
buttonState = digitalRead(BUTTON_PIN);
// control LED according to the state of button
if(buttonState == LOW) // If button is pressing
digitalWrite(LED_PIN, HIGH); // turn on LED
else // otherwise, button is not pressing
digitalWrite(LED_PIN, LOW); // turn off LED
}
Quick Steps
- Connect Arduino to PC via USB cable
- Open Arduino IDE, select the right board and port
- Copy the above code and open with Arduino IDE
- Click Upload button on Arduino IDE to upload code to Arduino
- Press and keep pressing the button several seconds
- See the change of LED's state
Code Explanation
Read the line-by-line explanation in comment lines of source code!
Video Tutorial
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