Going over material

Week 2

Lab 1 + Lab 2

Digital Input & Output

Lab: Sensor Change Detection

Push button as input

Push button as input

Push button as input LED as output

Push button as input LED as output

Code:

In words:

Expectations: When the button is pushed, the serial screen shows a message. Pin 13 LED lights up, waits for 2 seconds and turns off.

Output: As expected.

int lastButtonState = LOW;  // state of the button last time you checked

void setup() {
  // initialize serial communication:
  Serial.begin(9600);
  // make pin 2 an input:
  pinMode(2, INPUT);
  // make pin 13 output
  pinMode(LED_BUILTIN, OUTPUT);
}

void loop() {
  // read the pushbutton:
  int buttonState = digitalRead(2);

  digitalWrite(LED_BUILTIN, LOW);  // turn the LED off

  // if it's changed and it's high, toggle the mouse state:
  if (buttonState != lastButtonState) {
    if (buttonState == HIGH) {
      Serial.println("Button was just pressed.");
      digitalWrite(LED_BUILTIN, HIGH);  // turn the LED on (HIGH is the voltage level)
      delay(2000);
    }
  }
  // save button state for next comparison:
  lastButtonState = buttonState;
}

Code related Question:

Code Reference: https://itp.nyu.edu/physcomp/labs/labs-arduino-digital-and-analog/digital-input-and-output-with-an-arduino/