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Activity

Sound meter

Beginner | MakeCode, Python | LED display, Microphone | Data handling, Input/output

Step 1: Make it

What is it?

Measure how noisy it is around you using the new micro:bit's microphone sensor and a simple bar chart display.

Introduction

Coding guide

What you'll learn

  • How to use the new micro:bit's built-in microphone input sensor to measure how loud sounds are around you
  • How to display numerical data from input sensors graphically on the LED display output

How it works

  • The new micro:bit's microphone measures sound levels in numbers between 0 and 255. 0 is the quietest and 255 is the loudest sound measurement it can make.
  • The code uses a forever loop to keep the microphone measuring sound levels and plotting a bar graph on the LED display.
  • The louder the sounds measured, the higher the bar graph gets.

What you need

  • new micro:bit with sound (or MakeCode simulator)
  • MakeCode or Python editor
  • battery pack (optional)

Step 2: Code it

Step 3: Improve it

  • Create your own ways of displaying how loud a sound is, for example showing different emojis depending on how loud it is
  • Make a visual noise alarm that only flashes when the sound goes over a certain level - you could use this to help keep your classroom peaceful