Some of people like warm light and the other prefer cold light , so I want to make lighting unit with 2 or 3 lighting source , you can change warm or cold as you prefer , and to be suitable to your activities like " read , sleep , work ". If there are two partner in one place , every one of them can change the light type as he like.

Software: Arduino IDE

3 resistor 220 ohm

Arduino uno

Breadboard

Potentiometer

Jumper Wires (Male - Male)

3 Led with three colour (red-green-yellow)

LCD display 16x2

I searched online for something could change led light colour between three led light using Potentiometer and show numbers on lcd screen , every colour has number shown on screen

So I found this "Simple LED Meter Using Potentiometer and I2C LCD " and it will give me the same result .

Also I searched for simple lamp could be made by card board , I found Chinese lamp , I change the dimensions little bit to put breadboard .

the code :

#include <Wire.h>

#include <FastIO.h>

#include <I2CIO.h>

#include <LCD.h>

#include <LiquidCrystal.h>

#include <LiquidCrystal_I2C.h>

#include <LiquidCrystal_SR.h>

#include <LiquidCrystal_SR2W.h>

#include <LiquidCrystal_SR3W.h>

#include <Wire.h> //enables us to use i2c communication

#include <LiquidCrystal_I2C.h> //enables us to use the lcd functions

//I2C pins declaration

LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); //lcd is a user-defined name

int sensorValue = 0;

int led_1=4, led_2=5,led_3=6;

void setup()

{

lcd.begin(16,2);

lcd.backlight();

pinMode(led_1,OUTPUT);

pinMode(led_2,OUTPUT);

pinMode(led_3,OUTPUT);

}

void loop()

{

sensorValue=analogRead(A0);

sensorValue=map(sensorValue,0,1023,1,5);

lcd.clear();

lcd.setCursor(0,0);

lcd.print("Value is: ");

lcd.print(sensorValue);

delay(500);

if (sensorValue <= 2){ //sensorValue is less than or equal to 2

digitalWrite(led_1,HIGH);

digitalWrite(led_2,LOW);

digitalWrite(led_3,LOW);

}

else if (sensorValue==3){

digitalWrite(led_1,LOW);

digitalWrite(led_2,HIGH);

digitalWrite(led_3,LOW);

}

else if (sensorValue>=3){ //sensorValue is greater than or equal to 3

digitalWrite(led_1,LOW);

digitalWrite(led_2,LOW);

digitalWrite(led_3,HIGH);

}

}

I had two problems , first one when I wiring the circuit , one led work and the others didn't work , I try to change the resistor , the jumpers , the led , doesn't work . after a lot of tries I discover that the two led were on the other side in the bread board and the two sides didn't connect . so I move them in one side in the bread board

Second one , I can't add the LiquidCrystal_V1.2.1 to Arduino library , and the LCD didn't work and didn't show the value , and the code couldn't upload to Arduino

I search and found the way to add it to library through this website https://arduinointro.com/projects/displaying-characters-using-the-i2c-liquid-crystal-display-lcd

Step 1. First, download the LiquidCrystal_V1.2.1 and Wire zip files.

Step 2. Open your Arduino IDE and from the menu bar, go to Sketch->Include Library->Add .ZIP Library..

Step 3. Browse to where you saved the zip files and select one file at a time, then click Open. In this case, we select the LiquidCrystal_V1.2.1 zip file first.

After clicking Open, the library is now installed.

Step 4. Repeat the same process to include the Wire library.

My final project I am confused about using LCD to show the degree of temperature of cup of tea , or make led changing color by sensor feel the temperature , so I want to learn more about led and LCD and how to connect them with breadboard and how to write the code for them . so this Idea wad very useful for me.