Week 11: In-Class Exercises with Serial Communication

1. Make an ellipse in p5 move on the horizontal axis using only one sensor. Video Link

int leftLedPin = 4;
int rightLedPin = 6;
const int trigPin = 10;
const int echoPin = 9;

void setup() {
  // Start serial communication at 9600 baud
  Serial.begin(9600);

  // Set up the LED and ultrasonic sensor pins
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(leftLedPin, OUTPUT);
  pinMode(rightLedPin, OUTPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);

  // Blink LEDs to check wiring
  digitalWrite(leftLedPin, HIGH);
  digitalWrite(rightLedPin, HIGH);
  delay(200);
  digitalWrite(leftLedPin, LOW);
  digitalWrite(rightLedPin, LOW);
}

void loop() {
  // Check if there is data available from p5.js
  if (Serial.available()) {
    int left = Serial.parseInt();   // Get the left LED value
    int right = Serial.parseInt();  // Get the right LED value

    // Update LEDs based on values from p5.js
    digitalWrite(leftLedPin, left);
    digitalWrite(rightLedPin, right);

    // Clear any remaining characters in the serial buffer (such as '\n')
    Serial.read();
  }

  // Trigger the ultrasonic sensor
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // determine the time for the echo
  long timeTraveled = pulseIn(echoPin, HIGH);

  // the distance in centimeters
  int distance = timeTraveled * 3.4/2;
  
  int sensor = analogRead(A1);

  // Send the distance value to p5.js
  Serial.print(sensor);
  Serial.print(",");
  Serial.println(distance); 

  delay(100);  
}

 2. Control the LED brightness from p5 Video Link

const int blue_LED = 4;
const int red_LED = 6;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

  // Initalization of LED pins 
  pinMode(blue_LED, OUTPUT);
  pinMode(red_LED, OUTPUT); 

  // Blink LEDs to check wiring
  digitalWrite(blue_LED, HIGH);
  digitalWrite(red_LED, HIGH);
  delay(200);
  digitalWrite(blue_LED, LOW);
  digitalWrite(red_LED, LOW);

}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println(0);
  if (Serial.available()) {
    int left = Serial.parseInt();   // Get the left LED value
    int right = Serial.parseInt();  // Get the right LED value

    // Update LEDs based on values from p5.js
    digitalWrite(blue_LED, left);
    digitalWrite(red_LED, right);

    // removes remaining characters in the serial buffer
  }
  Serial.read();
  delay(100);
}

3. Gravity and Wind Video Link

const int LED_pin = 6;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode (LED_pin, OUTPUT);

  // digitalWrite(LED_pin, HIGH);
  // delay(200);
  // digitalWrite(LED_pin, LOW);

}

void loop() {
  // put your main code here, to run repeatedly:
  if (Serial.available()) {
    int LED_value = Serial.parseInt();   // Get the LED value

    // Update LEDs based on values from p5.js
    digitalWrite(LED_pin, LED_value);

    // Clear any remaining characters in the serial buffer (such as '\n')
    Serial.read();
  }
  
  int sensor = analogRead(A0);
  Serial.println(sensor); 
}