pinMode(ledPin,OUTPUT); // initialize the pushbutton pin as an input: pinMode(buttonPin,INPUT); } voidloop() { // read the state of the pushbutton value: buttonState=digitalRead(buttonPin); // check if the pushbutton is pressed. If it is, the buttonState is HIGH: if(buttonState=...
}voidloop() {//read the state of the pushbutton valuebuttonState = digitalRead(2);//check if pushbutton is pressed. if it is, the//buttonState is HIGHif(buttonState ==HIGH) {//turn LED ondigitalWrite(13, HIGH); }else{//turn LED offdigitalWrite(13, LOW); } delay(10);//Delay a...
because it's connected to ground through the resistor. When you press the button, the input is at 5v, because it's directly connected to 5v through the switch. The resistor doesn't matter when you press the button, it just makes sure that the input is at 0v when the button is not ...
An LED connected to digital output pin 9 through a 220 ohm resistor. 从数字针 9 连接 LED 并通过 220 欧姆电阻接地。 (3)电路示意图 - Schematic (4)代码解析 - Code In this example two loops are executed one after the other to increase and then decrease the value of the output on pin 9...
/*Button Turns on and off a light emitting diode(LED) connected to digital pin 13, when pressing a pushbutton attached to pin 2. The circuit: - LED attached from pin 13 to ground - pushbutton attached to pin 2 from +5V - 10K resistor attached to pin 2 from ground ...
//configure pin2 as an input and enable the internal pull-up resistor pinMode(2, INPUT_PULLUP); pinMode(13, OUTPUT); } void loop() { //read the pushbutton value into a variable int sensorVal = digitalRead(2); //print out the value of the pushbutton ...
int pushButton = 2; (4)设置函数 // the setup routine runs once when you press reset: 按下重置按钮后设置例程仅运行一次: void setup() { // initialize serial communication at 9600 bits per second: 初始化串口通信为 9600 bps Serial.begin(9600); ...
I chose such resistor values so that when fully charged battery to 4.2V is measured it would give 33k / (33k + 100k) * 4.2 = 1.04V. This is perfect, because the internal reference actually varies from chip-to-chip and can be in the range 1 - 1.2V. The chosen value would allow ...
http://www.arduino.cc/en/Tutorial/Button */ int buttonState = 0;void setup(){ pinMode(2, INPUT);pinMode(13, OUTPUT);} void loop(){ // read the state of the pushbutton value buttonState = digitalRead(2);// check if pushbutton is pressed. if it is, the // buttonState is ...
(When using a TIP120 as a switch we need to make sure it is fully saturated or it doesn’t turn all the way on). To ensure the TIP120 is fully saturated we lower the resistor value, I normally go with 2K2 and for the valve I am using could probably go to 1K. I’ll stay ...