Full sample code

/*
  Roboda verified Arduino sample 0052
  Feature: Digital Input Pullup
  Generated for online build, classroom practice, and hardware upload testing.
*/

const byte buttonPin = 4;
const byte outputPin = 13;

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

void loop() {
  bool pressed = digitalRead(buttonPin) == LOW;
  digitalWrite(outputPin, pressed ? HIGH : LOW);
  Serial.println(pressed ? "pressed" : "released");
  delay(150);
}

Teacher notes

• Compile the sample before changing wiring or constants.
• When changing boards, keep the code names the same and update only the pin number constants.
• For 3.3V boards, level-shift 5V sensors and modules before connecting signal pins.
• Use the first compiler error and the Roboda diagnostic suggestion before fixing later warnings.