/*   https://www.arduino.cc/en/Tutorial/BuiltInExamples/Button
*/

// constants won't change. They're used here to set pin numbers:
const int buttonPin = 2;  // pino que le a chave
const int ledPin = 8;    // pino que alimenta o led

int buttonState = 0;  // guarda o estado da chave

void setup() {
  pinMode(ledPin, OUTPUT); // pino saída para alimentar o led
  // initialize the pushbutton pin as an input:
  pinMode(buttonPin, INPUT); // pino entrada para ler a chave
}

void loop() {
  buttonState = digitalRead(buttonPin);
  // guarda valor digital do estado da porta
   if (buttonState == HIGH) { // acende o led
    // turn LED on:
    digitalWrite(ledPin, HIGH);
  } else {
    // turn LED off:
    digitalWrite(ledPin, LOW); // apaga o led
  }
}