Tag Archives: LED

Arduino Tutorial 36: Understanding How to Use Tilt Switches in Your Projects

November 12, 2019 admin

This Circuit Gives Visual Indicator if Board Has Been Tilted

This is a simple project that allows you to create a circuit which will give a visual indication if the breadboard has been tilted. In the upright position, the Green LED is illuminated. To the left of the board is a tilt switch. If the project is tilted, the switch will go from the closed to the open condition. This can be detected on the arduino, and then the red LED is illuminated. The video below explains how to do this simple project.

You can get the kit we are using in these lessons HERE. You should create your own code based on the instructions in the video, but if you are having trouble, I include the code developed in the video below:

int tiltPin=2;
int tiltVal;
int redPin=7;
int greenPin=6;

void setup() {
  // put your setup code here, to run once:
pinMode(tiltPin,INPUT);
pinMode(redPin,OUTPUT);
pinMode(greenPin,OUTPUT);
digitalWrite(tiltPin,HIGH);
Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
tiltVal=digitalRead(tiltPin);
Serial.println(tiltVal);
if (tiltVal==0){
  digitalWrite(greenPin,HIGH);
  digitalWrite(redPin,LOW);
}
if (tiltVal==1){
  digitalWrite(greenPin,LOW);
  digitalWrite(redPin,HIGH);
  
}
}

int tiltPin=2;

int tiltVal;

int redPin=7;

int greenPin=6;

void setup() {

// put your setup code here, to run once:

pinMode(tiltPin,INPUT);

pinMode(redPin,OUTPUT);

pinMode(greenPin,OUTPUT);

digitalWrite(tiltPin,HIGH);

Serial.begin(9600);

}

void loop() {

// put your main code here, to run repeatedly:

tiltVal=digitalRead(tiltPin);

Serial.println(tiltVal);

if (tiltVal==0){

digitalWrite(greenPin,HIGH);

digitalWrite(redPin,LOW);

}

if (tiltVal==1){

digitalWrite(greenPin,LOW);

digitalWrite(redPin,HIGH);

}

Arduino, Tutorial

Arduino Tutorial 29: Using Push Buttons to Create Dimmable LED

September 24, 2019 admin

In this lesson we show you how to create a Dimmable LED using two pushbuttons. Pressing one button will gradually increase the brightness, while pressing the other button will gradually decrease the brightness. The project also includes an active buzzer to provide the user feedback that either maximum or minimum brightness have been reached. I encourage you to try and build this yourself before watching the video. Then see if you can do it on your own, and then see if you are doing the way I do it, or if you find an alternative suitable solution.

If you want to follow along at home, you can order the Arduino Kit we are using HERE.

Below is the code we used to achieve the toggle operation. The video gives details on how to connect up the circuit.

int buttonPin1=12;
int buttonPin2=11;
int buzzPin=2;
int LEDPin=3;
int buttonVal1;
int buttonVal2;
int LEDbright=0;
int dt=500;
void setup() {
  // put your setup code here, to run once:
pinMode(buttonPin1,INPUT);
pinMode(buttonPin2,INPUT);
pinMode(LEDPin,OUTPUT);
pinMode(buzzPin,OUTPUT);
Serial.begin(9600);
}

void loop() {
buttonVal1=digitalRead(buttonPin1);
buttonVal2=digitalRead(buttonPin2);
Serial.print("Button 1 = ");
Serial.print(buttonVal1);
Serial.print(", ");
Serial.print("Button 2 = ");
Serial.println(buttonVal2);
delay(dt);
if (buttonVal1==0){
  LEDbright=LEDbright+5;
}
if (buttonVal2==0){
  LEDbright=LEDbright-5;
}
Serial.println(LEDbright);
if (LEDbright>255){
  LEDbright=255;
  digitalWrite(buzzPin,HIGH);
  delay(dt);
  digitalWrite(buzzPin,LOW);
  Serial.println("Buzz HIGH");
  
}
if (LEDbright<0){
  LEDbright=0;
  digitalWrite(buzzPin,HIGH);
  delay(dt);
  digitalWrite(buzzPin,LOW);
  Serial.println("Buzz LOW");
}

analogWrite(LEDPin, LEDbright);
}

int buttonPin1=12;

int buttonPin2=11;

int buzzPin=2;

int LEDPin=3;

int buttonVal1;

int buttonVal2;

int LEDbright=0;

int dt=500;

void setup() {

// put your setup code here, to run once:

pinMode(buttonPin1,INPUT);

pinMode(buttonPin2,INPUT);

pinMode(LEDPin,OUTPUT);

pinMode(buzzPin,OUTPUT);

Serial.begin(9600);

}

void loop() {

buttonVal1=digitalRead(buttonPin1);

buttonVal2=digitalRead(buttonPin2);

Serial.print("Button 1 = ");

Serial.print(buttonVal1);

Serial.print(", ");

Serial.print("Button 2 = ");

Serial.println(buttonVal2);

delay(dt);

if (buttonVal1==0){

LEDbright=LEDbright+5;

}

if (buttonVal2==0){

LEDbright=LEDbright-5;

}

Serial.println(LEDbright);

if (LEDbright>255){

LEDbright=255;

digitalWrite(buzzPin,HIGH);

delay(dt);

digitalWrite(buzzPin,LOW);

Serial.println("Buzz HIGH");

}

if (LEDbright<0){

LEDbright=0;

digitalWrite(buzzPin,HIGH);

delay(dt);

digitalWrite(buzzPin,LOW);

Serial.println("Buzz LOW");

}

analogWrite(LEDPin, LEDbright);

}

Arduino, Tutorial

Arduino Tutorial 25: Understanding Photoresistors and Photo Detectors

August 27, 2019 admin

In this lesson we learn how to use photoresistors. A photoresistor is a semiconductor material. In the darkness, it has almost no free electrons, so its resistance is very high. When light shines on the device, electron hole pairs are created, and these electron hole pairs are free to conduct electricity. This lowers the resistance of the material. The brighter the light, the more electron hole pairs that are generated, and hence the lower the resistance. Hence, the resistance of these devices is inversely proportional to the brightness of the light. By hooking a photoresistor in series with a fixed resistor, the current will change as the resistance of the sensor changes. This leads to a measurable change in the voltage across the series resistor. Hence, by measuring this voltage, you get a signal that is proportional to the light. This can be read via an analog pin on the Arduino, and then the arduino can be programmed to do different things based on the brightness of the light. In this simple project we have a red LED and a green LED. If the light is on, the green LED is turned on. If the light is off, the red LED is on.

If you want to follow along at home, you can order the Arduino Kit we are using HERE.

The nice digital voltmeter used in the lesson is available HERE.

Below is the code we developed in this video lesson above.

int lightPen=A0;
int lightVal;
int dv=250;
int redPin=9;
int greenPin=8;
void setup() {
  // put your setup code here, to run once:
  pinMode(lightPen,INPUT);
  pinMode(redPin,OUTPUT);
  pinMode(greenPin,OUTPUT);
  Serial.begin(9600);
}

void loop() {
lightVal=analogRead(lightPen);
Serial.println(lightVal);
delay(dv);
if (lightVal>350){
  digitalWrite(greenPin,HIGH);
  digitalWrite(redPin,LOW);
}
if (lightVal<350){
    digitalWrite(greenPin,LOW);
  digitalWrite(redPin,HIGH);
}

}

int lightPen=A0;

int lightVal;

int dv=250;

int redPin=9;

int greenPin=8;

void setup() {

// put your setup code here, to run once:

pinMode(lightPen,INPUT);

pinMode(redPin,OUTPUT);

pinMode(greenPin,OUTPUT);

Serial.begin(9600);

}

void loop() {

lightVal=analogRead(lightPen);

Serial.println(lightVal);

delay(dv);

if (lightVal>350){

digitalWrite(greenPin,HIGH);

digitalWrite(redPin,LOW);

}

if (lightVal<350){

digitalWrite(greenPin,LOW);

digitalWrite(redPin,HIGH);

}

Arduino, Tutorial

Arduino Tutorial 20: Understanding RGB LED’s

August 1, 2019 admin

In this lesson you will learn how to work with RGB LED’s. RGB LED’s can be used to create not only the primary colors, but also all mixtures of the primary colors. This video shows you how to connect up a Common Cathode RGB LED. This project is a little more complex than the ones we have done in the past, so I include the code down below. While the code is here for your reference, you should not just copy and paste it. In order to really learn, you need to type it in for yourself, and then find and debug your mistakes. If you just copy and paste from me, you will never learn how to troubleshoot.

int redPin=8;
int greenPin=9;
int bluePin=10;
String myColor;
String msg="What Colour Do You Want?";
void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode(redPin,OUTPUT);
pinMode(greenPin,OUTPUT);
pinMode(bluePin,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
Serial.println(msg);
while (Serial.available()==0){
  
}
myColor=Serial.readString();

if (myColor=="red"){
  digitalWrite(redPin,HIGH);
  digitalWrite(greenPin,LOW);
  digitalWrite(bluePin,LOW);
}
if (myColor=="green"){
  digitalWrite(redPin,LOW);
  digitalWrite(greenPin,HIGH);
  digitalWrite(bluePin,LOW);
}
if (myColor=="blue"){
  digitalWrite(redPin,LOW);
  digitalWrite(greenPin,LOW);
  digitalWrite(bluePin,HIGH);
}
if (myColor=="off"){
  digitalWrite(redPin,LOW);
  digitalWrite(greenPin,LOW);
  digitalWrite(bluePin,LOW);
}

if (myColor=="aqua"){
  digitalWrite(redPin,LOW);
  analogWrite(greenPin,255);
  analogWrite(bluePin,80);
}
}

int redPin=8;

int greenPin=9;

int bluePin=10;

String myColor;

String msg="What Colour Do You Want?";

void setup() {

// put your setup code here, to run once:

Serial.begin(9600);

pinMode(redPin,OUTPUT);

pinMode(greenPin,OUTPUT);

pinMode(bluePin,OUTPUT);

}

void loop() {

// put your main code here, to run repeatedly:

Serial.println(msg);

while (Serial.available()==0){

}

myColor=Serial.readString();

if (myColor=="red"){

digitalWrite(redPin,HIGH);

digitalWrite(greenPin,LOW);

digitalWrite(bluePin,LOW);

}

if (myColor=="green"){

digitalWrite(redPin,LOW);

digitalWrite(greenPin,HIGH);

digitalWrite(bluePin,LOW);

}

if (myColor=="blue"){

digitalWrite(redPin,LOW);

digitalWrite(greenPin,LOW);

digitalWrite(bluePin,HIGH);

}

if (myColor=="off"){

digitalWrite(redPin,LOW);

digitalWrite(greenPin,LOW);

digitalWrite(bluePin,LOW);

}

if (myColor=="aqua"){

digitalWrite(redPin,LOW);

analogWrite(greenPin,255);

analogWrite(bluePin,80);

}

In these lessons, we are using the Elegoo Arduino kit, which you can purchase HERE.

Arduino, Fusion 360

Arduino Tutorial 14: Dimmable LED Project

July 16, 2019 admin

You have actually learned quite a bit in the first 13 lessons, and now we are ready to bring it all together in an interesting project. In this lesson, we will show you how to build a dimmable LED. You will read values from a potentiometer, and then based on what value you read, you will set the brightness of the LED. This is a really cool little project, and will no doubt get you thinking about bigger and better things. If you want to follow along at home, you can order the Arduino Kit we are using HERE.

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Tag Archives: LED

Arduino Tutorial 36: Understanding How to Use Tilt Switches in Your Projects

Arduino Tutorial 29: Using Push Buttons to Create Dimmable LED

Arduino Tutorial 25: Understanding Photoresistors and Photo Detectors

Arduino Tutorial 20: Understanding RGB LED’s

Arduino Tutorial 14: Dimmable LED Project

Making The World a Better Place One High Tech Project at a Time. Enjoy!