Design a program to control the LED ‘traffic light’ in the photo.

Build the following circuit, connecting a buzzer to the 8th pin of an Arduino board. Open the example toneMultiple from File >Examples >Digital and check the result. Explain here your steps.

How can we add a sound effect to the traffic light when it is red? Your work in the two previous activities will help you.

Modify the program that controls the series port. When you push the button, the message “You are pushing me” should appear on the screen.

Build the circuit that is described in this section in the simulator 123d.circuits.ico (Computer application section). Try using the series port, too.

Add a second LED to the example on the previous page. This second LED should blink when the button is pushed. The first LED should blink when the button is released.

Control program :

const int   pinPushbutton = 3; // we define the pins

const int   pinLED = 13;

int   pushbuttonOn; // variable that stores the state of the push button

void setup() {

     // we configure inputs and outputs

     pinMode(pinLED, OUTPUT);

     pinMode(pinPushbutton, INPUT);

}

void loop(){

     // we read the state of the push button

     pushbuttonOn = digitalRead(pinPushbutton);

     // if pressed we switch on the LED

     if (pushbuttonOn == HIGH) {

         digitalWrite(pinLED, HIGH);

}

  else {

     // if not pressed we switch it off

     digitalWrite(pinLED, LOW);

  }

}

What will happen to the LED if we replace the voidloop() function with the commands in the margin?

void loop() {

    for (int lightLED = 0; 

    lightLED <= 255; lightLED += 5) {

    analogWrite(pinLED, lightLED);

    // we wait 25 milliseconds:

    delay(25);

   }

}

Draw the shape of a signal that leaves the axis at 45 degrees.

Look at the servomotor above. What does it do?

#include <Servo.h>

//Name of servo:

Servo myServo;

void setup(){

  //Connected to pin 9:

     myServo.attach(9);

}

void loop(){

     myServo.write(0);

     delay (4000);

     myServo.write(180);

     delay (4000);

}

Complete the circuit and control program for an electric gate that controls access to a car park.

Find out if a sweep servomotor can be converted into a continuous rotation servomotor, and how to do it.

How would you design a robot that avoids obstacles as it moves around? What would you add to the previous program?

How can a robot follow a black line painted on a white floor?

An encoder lets us measure the speed of a rotating wheel. Can you guess how it works?