How to Control LED Lights with Microcontroller

How to control LED lights with simple buttons on a microcontroller?

Microcontroller has become an indispensable core component in modern electronic products. It helps designers integrate a variety of different electronic components together to realize a wide range of functions. Microcontrollers have many uses, but one of them is to control external devices such as LED lights. In this article, we will explore in detail how to control LED lights with a simple keystroke.

The Basics of Microcontrollers

Before we start exploring the specifics, we need to understand some basics, including what a microcontroller is and how to install and configure an integrated development environment (IDE). Microcontrollers are microcomputers that typically consist of a processor, memory, input/output ports, and other electronic components. They are somewhat similar to PCs, but they are smaller, cheaper, more durable, and consume less power.

Before we start working with microcontrollers, we need to install or select an integrated development environment (IDE). This software helps us to edit, compile and upload code. For beginners, Arduino IDE is a good choice. It has support for many different types of microcontrollers and is easy to use.

Next, we need to understand some basic programming generalities. We will use C to write the code, as it is a common language used for microcontroller programming.

Hardware materials

Next, we need to prepare some hardware machine parts to accomplish our task. We need the following components:

• 1. a microcontroller board. In this article, we will use Arduino Uno.
• 2. an LED.
• 3. a resistor.
• 4. two Dupont wires.
• 5. a switch button.
• 6. a breadboard.
• 7. connecting tools, etc.

In this project, we will use the breadboard to provide power and connections for all the devices. We will connect all the devices to the breadboard.

Connecting LEDs and Resistors

First we need to connect the LED to the microcontroller.The LED is called an output port in the microcontroller and then we need to connect it to a pin. Many microcontroller boards have pins that can be connected directly to the LED, but in our project we will connect the LED to pin 3 because it is a programmable pin and we can use it later in the program.

The microcontroller cannot drive the LEDs directly because the LED zero resistance current is too low. We need a resistor to limit the current in the circuit and to prevent the LEDs from drawing too much power. We will use a 330 ohm resistor to connect the LED to the microcontroller.

Connecting the Switch Button

Next, we will connect the switch keypad to the microcontroller. The button is an input port in the microcontroller and we need to connect it to a pin on the microcontroller to enable it to receive signals from the switch. We will use pin 2 as the input port.

As with the LED, the microcontroller cannot read the switch state directly. We need to use a resistor on the switch to direct the input current, which helps to read the state of the switch more accurately. We will use a 10k ohm resistor to connect the switch to the microcontroller so that its value goes high. When the switch is pressed the pin will be energized by the electrode then the level value on the pin will change to low.

Writing the program

Now that we have a list of hardware devices, let's look at how to write a program to control the LEDs and read the switch status.

We need to let the microcontroller know which pin we want to use. In the Arduino IDE, we need to specify either an input pin or an output pin with the pinMode() function. In our program, we will set pin 2 as input port and pin 3 as output port as shown below:

```

void setup() {

pinMode(2, INPUT); //set pin 2 as input port

pinMode(3, OUTPUT); //set pin 3 as output port

}

``

Next, we need to write a program that will read the state of pin 2 and control the state of pin 3 according to the different states. In our program, if the key is pressed then the LED lights up and stops pressing the key and the LED goes off. The program is as follows:

``

void loop() {

if(digitalRead(2)==HIGH) { //if pin 2 is turned on

digitalWrite(3, HIGH); //LED lights up

}

else {

digitalWrite(3, LOW); //LED off

}

}

``

Our program is complete! When the switch is pressed the LED will light up and when the button is released the LED will go out. Now we can upload the program to the microcontroller and test that it works.

Summarize

In this article, we have learned how to control LED lights using microcontroller and manipulate them using simple keystrokes. We discussed the basics of microcontrollers, installed and configured the IDE, connected LEDs and resistors, switches and resistors, and finally wrote a program to make the LEDs go on and off with the switching of a key. This was a very short and simple project, but provided us with a basic template showing how to use the microcontroller to control external devices, inspiring us to undertake more complex microcontroller projects.