Microbit Inventor Project
Beginner
30 mins
85 points
What you need:
  • Computer/laptop
  • Microbit

Sound level

Using the microphone in a Microbit, turn a Microbit into a sound level detector.

1 - Create a new Microbit project

Go to the makecode.com website and create a new Microbit project.

2 - Show the sound level as a graph

Microbits (version 2) have a microphone built into them that can detect sound. The sound level that is detected by the microphone is stored in the sound level block. It stores a number between 0 (low sound) and 255 (loud sound).

Using the plot bar graph of 0 up to 0 block (from the Led toolbox), we can display a graph on the Microbit that shows the current level of sound that is being detected.

Add the following code to your project.

basic.forever(function () {
    led.plotBarGraph(
    input.soundLevel(),
    255
    )
})

A bar graph is a kind of chart that shows numbers as lines with different lengths.



3 - Challenge!

Do you want to turn your Microbit into a warning device that protects your room from unwanted visitors when you're not there?

Use the sound level block to monitor the sound level and if it goes above a certain loudness then use the speaker in your Microbit to sound the alarm!

Have a think about what code you will need to add and then try and code it.

see answer

basic.forever(function () {
    led.plotBarGraph(
    input.soundLevel(),
    255
    )
    if (input.soundLevel() >= 100) {
        for (let index = 0; index < 4; index++) {
            soundExpression.giggle.playUntilDone()
        }
    }
})
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