CH26-D - Servo Potentiometer Step

The 270 Degree Servo Motor has a 3-wire connector on the end that can plug directly into the pins on the back of the Bit Board.

Make sure the Orange Wire is closest to the number 13 for the Pin 13 column.

Then the Brown Wire should be closest to the micro:bit (in the - row) and the Red Wire will be in the middle (the +5v row).

We'll need to connect one side of the Potentiometer to Ground (GND) and the other side to 3.3v

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.)

The other analog pins are 1, 2, 3, 4, and 10. See this chart for a pinout diagram: https://makecode.microbit.org/device/pin...

You'll notice the Ground on the Bit Board is color coded White.

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.)

If you've never used a micro:bit before you'll want to check out this guide: Bit Board V2 Setup and Use

We're going to load the following code for our Servo Potentiometer Step program: https://makecode.microbit.org/_CgYJieX9Y...

Our Potentiometer will function like a four-position rotary switch.

The code will check the value of the Potentiometer and determine what angle to set the Servo based on the potVal variable.

Where does the 60 come from? If we divide 180 by 4 we get 45... but we need to divide 180 by 3 because we also need the 0 (zero) position, so 180 / 3 = 60.

We do (almost) the same thing with the Potentiometer value, though the math gets tricky because 0 to 1023 is 1024 values, so when we count the first 256 values we use 0 to 255. (Math gets weird when you include zero)

Once the code is loaded it should start running immediately.

You can power the micro:bit via the USB cable you used to load the code, but now that we are using servos we recommend using a battery pack plugged into the Bit Board.

The Blue Pins on the Bit Board provide extra power (5 volts instead of 3 volts) by boosting the voltage coming from the battery pack. This helps improve servo performance, especially with multiple servos.

Turn the Potentiometer dial to move the Servo to one of four different positions/angles.

Follow along with our recorded Live Stream!

You can watch the full video of us walking through this project, along with explaining and exploring the code: https://youtube.com/live/7ulebPcKk2A