const int buttonPin = 27; // the number of the pushbutton pin

const int ledPin = D7;

// the number of the LED pin

bool flag = false;

  

// variables will change:

int buttonState = 0; // variable for reading the pushbutton status

  

void setup() {

// initialize the LED pin as an output:

pinMode(ledPin, OUTPUT);

// initialize the pushbutton pin as an input:

pinMode(buttonPin, INPUT);

}

  

void loop() {

// 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 == HIGH)

{

if(flag = !flag); //flag=!flag

  

}

digitalWrite (ledPin, flag);

}