Distance Display

Gather your components. You will need a micro:bit, a Bit Board, Jumbo 10mm LED, Ultrasonic Distance Sensor, 7 Segment Display, and some 1/8" Maker Tape.

Make sure to view the PDF for a full diagram and more information about this project.

Build on a LEGO baseplate with a few LEGO pieces used to raise up the Bit Board on the edges.

Add the LED as show, connecting it to Pin 8 and Ground with Maker Tape.

Make sure you have the polarity correct for your LED or it will not light up. Positive goes to Pin 8. Negative goes to Ground.

Add the Ultrasonic Distance Sensor by connecting it to the header pins on the back of the Bit Board using jumper wires.

You can use any color jumper wire for your connections, just make sure they are connected to the correct pin.

It can be easier to plug in all the jumper wires before plugging your micro:bit into the Bit Board.

You'll notice a high-tech solution to mounting our sensor and our display... rubber bands and LEGO!

Add the 7 Segment Display by connecting jumper wires to the correct pins on the module and the Bit Board.

You should now have your LED connected with Maker Tape, and your sensor and display connected with jumper wires.

In the next few steps we'll walk you through how to add code extensions.

This is meant to be informational, and you can follow along if you like, but if you use the code we provide it will all automagically work.

If you already know how to add code extensions you can skip to Step 8 where we provide the code.

In the MakeCode editor, click on Extensions under the Advanced menu on the left.

You'll go to the extension repository where you can browse or search for extensions.

We're going to type TM1637 into the search bar, and we should get the TM1637 as a result.

Click on it to add it to your program. This will allow us to use our 7 Segment Display.

After it is added you'll see it appear in the left menu.

Now we'll add the Sonar extension using the same procedure.

This extension will allow us to use the Ultrasonic Distance Sensor in our program.

For our new extensions you can click on their names in the left menu and you'll see the new functionality you now have in your program.

Some extensions add a lot of new functions, and some are quite minimal, adding just a few new functions.

Connect a USB cable to the micro:bit and then plug it into your computer.

We'll be using makecode.microbit.org to program our board. It uses a simple drag and drop block interface.

We're going to load the following code for our Distance Display program: https://makecode.microbit.org/_VHVhgkV43...

Once the code is loaded you should start to see numbers on the display.

The included PDF has more information about the code if you want to dig deeper.

Once you've got everything assembled and you've loaded your code, you can test it out!

Move your hand towards and then away from the sensor. You should see the numbers change, showing the distance your hand is from the sensor in centimeters.

If something isn't working right, double check all of your connections and make sure you've loaded the code properly.

Our program is pretty simple, and you should be able to figure out how to change the numbers that cause the LED to turn on as a starting point to expanding this project.

Maybe you can add a Piezo Speaker and play a tone or a melody when someone gets too close.

You could also add more LEDs and have different LEDs turn on to indicate different distances.

Like many circuits, we've got a cause and effect thing going on. Think about what you want to happen when an object is a certain distance from the sensor, and work through what is involved in altering the circuit (or the code) to do what you want.