How to use the MQ2 sensor with Microbit board | Gas Level monitoring system with MicroBit

Hello and welcome back. In this tutorial, we will learn how to use the MQ2 sensor with Micro:bit board. The MQ2 sensor can detect gases like LPG, smoke, carbon monoxide, and methane, making it useful for safety and environmental monitoring projects. I’ve also added a buzzer for alerts and an OLED display to show sensor readings in real time. This creates a simple gas-level detection system that demonstrates how the sensor works. In addition, this tutorial covers how to set up and program the OLED display with the microbit board. For coding, I used the MakeCode platform, which lets you create programs with block-based coding, JavaScript, or Python. If you’re a beginner, I recommend starting with the block coding. Then you can see the auto-generated Java and Python codes. You can use this tutorial to learn how to make LP gas and smoke detection systems. OK let’s go ahead.

What is the MQ2 sensor – Click on me
What is the OLED display – Click on me

OK, let’s do this project step by step. The required components are given below.

Microbit board — Our store / Amazon
MQ2 sensor x 1 — Our store / Amazon

Buzzer x 1 — Our store / Amazon
OLED display x 1 — Our store / Amazon
Microbit sensor shield — Our store / Amazon

Jumper wires — Our store / Amazon
Keyestudio BBC Micro: bit starter kit — Click on me

Step 1

Firstly, identify these components.

Step 2

Secondly, connect the microbit board to the sensor shield.

Step 3

Thirdly, connect the mq2 sensor, buzzer, and OLED display to the sensor shield. For that, use the circuit diagram below.

Step 4

Now, connect the microbit board to the computer. After, let’s make a program for this project. For that, follow the instructions below.

First, go to the Makecode website and create a new project as you like.

Then, include the OLED extension. Afterward, copy and paste the following Python script into the Python tab. Now you can see the auto-generated code blocks. Otherwise, you can make this code along with code blocks.

Python script — Download

value = 0
OLED12864_I2C.init(60)
OLED12864_I2C.show_string(2, 0, "GAS Level", 1)
OLED12864_I2C.show_string(1, 1, "Monitoring", 1)

def on_forever():
    global value
    value = pins.analog_read_pin(AnalogReadWritePin.P2)
    OLED12864_I2C.show_string(5, 2, "" + str(value) + " ", 1)
    if value >= 250:
        pins.digital_write_pin(DigitalPin.P5, 1)
        OLED12864_I2C.show_string(3, 3, "Warning!", 1)
        basic.show_leds("""
            . . # . .
            . . # . .
            . . # . .
            . . . . .
            . . # . .
            """)
    else:
        pins.digital_write_pin(DigitalPin.P5, 0)
        OLED12864_I2C.show_string(3, 3, "         ", 1)
        basic.clear_screen()
basic.forever(on_forever)