If it still doesn’t work after that, I would conclude that you have a bad resistor or your analog pin 0 has somehow been damaged (the latter is really unlikely). These are the readings I got with a 200 Ohm “unknown” resistor:įirst, check all your connections, and also verify that you have updated the sketch with the new resistance value for R1. After you’ve got the LCD set up, connect the Ohm meter as shown above, and upload this program to the Arduino: #include That will show you how to connect everything. First you’ll want to read our tutorial on setting up an LCD display on the Arduino. One reader commented that they would like to display the resistance measurements on an LCD. Vout: is the voltage drop across your unknown resistor.R2: is the resistance of your unknown resistor in Ohms.When you open up the serial monitor you’ll see the resistance values printed once per second. There will be two values, R2 and Vout. You can use any other analog pin though, just change the pin number in line 1, and wire the circuit accordingly. The program sets up analog pin A0 to read the voltage between the known resistor and the unknown resistor. Therefore, my line 5 should look like this: float R1 = 1000. In my case, I’m using a known resistor with a value of 1K Ohms (1000 Ohms). The resistors we use here are 100 ohms (Brown Black Brown rings).Now, enter this code into the Arduino IDE and upload it to your board: int analogPin = 0 Įnter the value of your known resistor (in Ohms) on line 5 of the code above. The purpose of the resistors is to limit the amperage in the circuit and hence protect the LED from receiving a too strong current (which could damage the LED). This is how we will connect our RGB LED to our Arduino board. It has 3 cathodes (+ pins) that can take different amperages. It consists of a RED LED, a Green LED and a Blue LED all within the same component. This code consists of three numbers between 0 and 255, indicating how much red, green and blue are used to recreate the colour.Ĭheck the following RGB Color picker to see how RGB codes work:Īn RGB LED is a 3-in-1 LED. Open Tinkercad in new windowĭid you know that every colour on the screen can be represented using an RGB code (Red, Green, Blue) code. Instead you can use the online Arduino simulator from Tinkercad to recreate the electronic circuit and add the code provided below. You do not need to have access to an Arduino board. In this challenge we will use the Arduino board to control a RGB LED to create a gradient light effect where the LED will fade from red to purple, to blue, to purple and back to red.

Arduino resistor color code