Overview

In this guide we will create a simple knob sketcher toy using a graphical display and two potentiometers, also known as trim pots or just pots. We'll go over the basic idea of drawing a pixel to the display as well as how to use the pots to generate a variable voltage. The two concepts will be put together to create a couple different variations of a knob sketcher toy.

Parts

This guide uses an Adafruit ItsyBitsy M4 Express as the main board. However, you could adapt this to other boards that run CircuitPython and have the available pins. You might need to change the example code to match the pins for your board.

Adafruit ItsyBitsy M4 Express featuring ATSAMD51

PRODUCT ID: 3800
What's smaller than a Feather but larger than a Trinket? It's an Adafruit ItsyBitsy M4 Express featuring the Microchip ATSAMD51! Small,...
$14.95
IN STOCK

The other key part for this project is a graphical display. This guide uses the two displays below, but you could also substitute for other similar displays as long as there is a CircuitPython driver available.

Monochrome 1.3" 128x64 OLED graphic display

PRODUCT ID: 938
These displays are small, only about 1.3" diagonal, but very readable due to the high contrast of an OLED display. This display is made of 128x64 individual white OLED pixels,...
OUT OF STOCK

Monochrome 2.42" 128x64 OLED Graphic Display Module Kit

PRODUCT ID: 2719
If you've been diggin' our monochrome OLEDs but need something bigger, this display will delight you! These displays...
$39.95
IN STOCK

You'll need a pair of potentiometers also. The two options used in this guide are linked below. Pots are also pretty common things, so any similar ones would likely work.

Breadboard trim potentiometer

PRODUCT ID: 356
These are our favorite trim pots, perfect for breadboarding and prototyping. They have a long grippy adjustment knob and with 0.1" spacing, they plug into breadboards or...
OUT OF STOCK

Panel Mount 10K potentiometer (Breadboard Friendly)

PRODUCT ID: 562
This potentiometer is a two-in-one, good in a breadboard or with a panel. It's a fairly standard linear taper 10K ohm potentiometer, with a grippy shaft. It's smooth and easy...
$0.95
IN STOCK

In addition, you'll need a breadboard and some hookup wires. A button is used for the second knob sketcher. Details are provided later in the guide.

Full sized breadboard

PRODUCT ID: 239
This is a 'full-size' breadboard, 830 tie points. Good for small and medium projects. It's 2.2" x 7" (5.5 cm x 17 cm) with a standard double-strip in the middle...
$5.95
IN STOCK

Breadboarding wire bundle

PRODUCT ID: 153
75 flexible stranded core wires with stiff ends molded on in red, orange, yellow, green, blue, brown, black and white. These are a major improvement over the "box of bent...
$4.95
IN STOCK
This guide was first published on Dec 30, 2018. It was last updated on Dec 30, 2018. This page (Overview) was last updated on Aug 08, 2019.