Introduction
Connect a 7 Segment Display and a Potentiometer to a Bit Board and control them with code.
We'll explore code to control a 7 Segment Digital Display that can show numbers up to 9999.
Video Overview
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We'll connect the 7 Segment Display with a Crazy Circuits Ribbon Cable using all four wires.
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Start by plugging the connector with the three wires in it (Black, Red, Yellow) into the Pin 1 row of the Bit Board. (Make sure the Black wire is in - and the Yellow wire labeled S1 is closest to the number 1 on the Bit Board.) We can then plug the Orange wire labeled S2 into Pin 0 on the Bit Board.
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Now we'll connect the other end of the Ribbon Cable to the 7 Segment Display. The pin labels are on the back of the 7 Segment Display PCB. From top to bottom it's CLK, DIO, VCC, GND.
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CLK stands for Clock and DIO stands for Data Input/Output. VCC is the Positive (+) and GND is the Ground (-) or Negative.
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S2 (Orange) goes to CLK, S1 (Yellow) goes to DIO, and then + (Positive) goes to VCC and - (Ground or Negative) goes to GND.
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We'll need to connect one side of the Potentiometer 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, which we'll need for the Potentiometer.)
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We used a 3D printed holder we designed to hold the 7 Segment Display in place on the LEGO baseplate.
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You can find the guide for the holder here: 7 Segment Display Holder
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Alternately you can use some LEGO bricks and a rubber band or tape to hold the display in place.
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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 7 Segment Display Potentiometer Values program: https://makecode.microbit.org/_6roiPLi9p...
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In the on start block we'll set up our display using the pins we've connected. CLK to Pin 0 and DIO to Pin 1.
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In our forever block we'll just clear the display and then use the show number function to display the raw value from the Potentiometer that we'll read on Pin 0.
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Once the code is loaded it should start running immediately but won't display anything until we turn the dial.
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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 Potentiometer dial and you should see the number on the 7 Segment Display change.
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You'll notice that you probably won't get values from 0 to 1023, which you might expect, since that is the range of the analog pins on the micro:bit
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In fact you may not even see consistent results at the leftmost and rightmost ends of the dial.
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Follow along with our recorded Live Stream!
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(We'll add the video to this step after we do the stream!)
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