Arduino - Button - Relay
We are going to learn how to:
- Turn on relay if button is pressing.
- Turn off relay if button is NOT pressing.
We will learn how to toggle relay each time button is pressed in Arduino - Button Toggles Relay tutorial.
By connecting relay to light bulb, led strip, motor or actuator... We can use the button to control light bulb, led strip, motor or actuator...
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-relay
*/
const int BUTTON_PIN = 7; // Arduino pin connected to button's pin
const int RELAY_PIN = 3; // Arduino pin connected to relay's pin
void setup() {
Serial.begin(9600); // initialize serial
pinMode(BUTTON_PIN, INPUT_PULLUP); // set arduino pin to input pull-up mode
pinMode(RELAY_PIN, OUTPUT); // set arduino pin to output mode
}
void loop() {
int buttonState = digitalRead(BUTTON_PIN); // read new state
if (buttonState == LOW) {
Serial.println("The button is being pressed");
digitalWrite(RELAY_PIN, HIGH); // turn on
}
else
if (buttonState == HIGH) {
Serial.println("The button is unpressed");
digitalWrite(RELAY_PIN, LOW); // turn off
}
}
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 relay's state
Code Explanation
Read the line-by-line explanation in comment lines of source code!
Video Tutorial
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