Introduction
Connect a potentiometer to a Bit Board and control an LED.
We'll explore how we can use a potentiometer as an input for the micro:bit and control the output of an LED.
Video Overview
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We'll use Maker Tape to connect the Potentiometer and LED to the Bit Board on a LEGO baseplate.
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The LED will connect to Pin 8 and to Ground (GND) BUT! We're going to use the "gutter" between the LEGO baseplate studs so we can have two layers of tape that do not touch.
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See the photos to show how this works. It's a technique we'll use for certain projects. It can also be used when you're tight on space for tape paths.
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Once the LED is connected we'll need to connect the Potentiometer. One side goes to Ground (GND) and the other side to 3.3v
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We will then connect the center of the Potentiometer to Pin 0. (Note that Pin 0 is an analog pin.)
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You'll notice the Ground on the Bit Board is color coded White.
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The 3.3v hole on the Bit Board is labeled and is actually two holes right next to each other on the Bit Board. (There is a small line showing the connection between them.)
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If you've never used a micro:bit before you'll want to check out this guide: Bit Board V2 Setup and Use
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We're going to load the following code for our Potentiometer LED Blink program: https://makecode.microbit.org/_6XFgiq1Co...
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Our code will use a function we created named blink to drive Pin 8 high and low which will make the LED turn on and off. We're also going to pass a number (the variable num) to the function.
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You'll notice we're also doing some math to set our pauseValue. Remember, anywhere a number is expected you can do math on the number.
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In the forever loop we'll actually use the Potentiometer (along with the map function) to set potValue and then pass that into the blink function.
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Note that we aren't using the Potentiometer to adjust the brightness this time, but to change the rate at which the LED blinks on and off.
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Once the code is loaded it should start running immediately.
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You can power the micro:bit via the USB cable you used to load the code or you can use a battery pack plugged into the Bit Board.
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Turn the small blue knob on the Potentiometer and you'll see the LED blink and the rate of blinking change as you turn the dial.
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Follow along with our recorded Live Stream!
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You can watch the full video of us walking through this project, along with explaining and exploring the code: https://youtube.com/live/1FlnatERZ94
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Attached Documents
