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Elecfreaks Sonar:bit for micro:bit Ultrasonic Sensor Distance Measuring 3V/5V


Elmwood Electronics has stopped accepting orders. This product might be available at PiShop.ca. Please check this blog post about our recent team merger.

Sonar:bit is an ultrasonic module with 3-5V voltage range. It can be used with 3.3V or 5V micro-controller systems only requiring a single 3-wire(GVS) cable. Compared to normal 4-wire ultrasonic modules, this saves one IO port.

The measurement range of sonar:bit is 4cm-400cm. It can output stable and accurate measurement data with ±1cm tolerance. You can use this module for short-distance measurement, smart cars, robots, micro:bit and Arduino instruction, Raspberry Pi, etc.


  • Input voltage:3V~5V
  • Enable to drive micro:bit or Arduino directly.
  • Standard 3-wire GVS connector, which occupies 1 I/O port only.

Definition of Pins


Introduction of Major Components


Transmitter is used to send ultrasonic signals.



Receiver is for collecting ultrasonic signals.


This is the master chip of sonar:bit.

Chip for Sending Signal

This chip is used to drive the transmitter to send out ultrasonic signals.

Chip for Receiving Signal

This chip is used to receive and process ultrasonic echo signals as well as give feedback to the master chip.

G-V-S Port

G-V-S port allows external device control.

Quick Start

Hardware Connection

Connect sonar:bit to P2 port on sensor:bit and connect micro:bit to your computer.


Open Makecode online editor.

Write your program to assign the returned value of P2 to variable distance and display it on micro:bit screen.

You can see the whole program from the link here: https://makecode.microbit.org/_b7JL2Yd3q3Km

We can see the distance between sonar:bit and the object is displayed on micro:bit in real time. The units are in centimeters.



Packing List

  • 1 x Sonar:bit
  • 1 x GVS Jumper Cable


Sonar:bit Guide

Collections: ElecFreaks, micro:bit

Type: micro:bit add on