In this tutorial & video, I will show you how to control blinking speed of an LED using Arduino Nano & a variable resistor or a potentiometer aka the pot (short form of potentiometer).
This tutorial is similar to an LED blink code but, we added a pot to it, you may think that what is pot, basically pot is a type of resistor which value can be changed. It has three legs, 1 leg on each side which are rigid and are connected to each other with the small layer of conductor & 1 is in center which is movable means we can rotate it & it has a small pin which floats on this thin layer. For example, we connect GND to one leg & 5V to another leg, Now when we rotate the center pin to GND leg, the voltage passing through center will decrease & when we rotate it to 5V, the voltage passing through center pin will increase & if we rotate it to center the voltage will be half of the 5V, means 2.5V. understand !!
Now get back to our tutorial,
Things we will need :
A Arduino board ( I took Nano).
A LEDA resister ( 150 ohm )
A potentiometer ( yes, pot )
Full video of the tutorial :
Step 1: Wiring
Firstly, place the Nano, an LED & resistor on the bread board.
- Now, connect the Nano's 5V & GND to breadboard's power lines.
- Connect one end of resistor to Nano's D13 pin & other end to an LED's anode pin or say long leg.connect cathode or short leg to the GND.
- Now place the pot on breadboard.
- First leg of pot to GND.second to Nano's analog pin A0 &third to 5V.
Our wiring is now let's move to coding part.
Step 2: Coding
Connect Nona to PC through the USB cable & open Arduino IDE.
Now go to File > Examples > Analog > AnalogInput. A sketch will open, upload it to the Nano.
when uploading is done, you can change the blinking speed of an LED with the pot.
How the code works.
You may remember, in an LED code, we took 1000 ms as delay between HIGH & LOW, means an LED remains 1 second HIGH & 1 second LOW. In this example, Arduino takes the voltage form the center leg of pot & converts it to digital form (0 - 5 to 0 - 1023). So, when we rotate the nob of the pot to 0V, we are actually decrease the time between HIGH & LOW & when we rotate the nob of the pot to 5V, we are actually increase the time between HIGH & LOW. Simple but effective way to control blinking speed of an LED.