digitalreadserial

Other Hardware Displays
1

I can not get the screen output, no result shows on the screen.

2

Try this:

Upload this sketch to your Arduino board:

void setup() {
  Serial.begin(9600);
}

void loop() {
  Serial.println("hello");
  delay(1000);
}

Tools > Serial Monitor
Select "9600" from the baudrate menu at the bottom right corner of the Serial Monitor window.