Using buttons with Arduino (no pull-up resistor)

This is a sample code for using buttons in Arduino.
It's not well known, but when you use a pull-up, you can easily use the buttons with no pull-up resistance.
If you connect the Ground to the second port of the Degital (by pressing the button), you will be aware of this.

	const int buttonPin = 2;

	void setup() {
	Serial.begin(9600);
	pinMode(buttonPin, INPUT_PULLUP);
	}

	void loop(){
	//ボタンが押されているとbuttonPinがGNDに落ちるのでLOWになる
	if (digitalRead(buttonPin) == LOW) {
	Serial.println("PushPush");
	} else {
	Serial.println("Not Push");
	}

	delay(1000);
	}

view raw ButtonTest.ino hosted with ❤ by GitHub