Parts

Get the parts ready to wire up. Take a moment to cross check the parts list for this project.

• 1x Rotary Encoder
• 1x 1.3 OLED
• 3x potentiometers
• 1x KB2040
• 5x CHOC key switches
• 5x CHOCK key sockets
• 1x STEMMA QT cable (100mm long)

Wire for Keys

Use the white colored spool of wire to create a set of five wires that are approximately 4.5" inches (115mm) long.

Use the blue colored spool of wire to create four wires that are approximately 1" inch (25mm) long.

Cut a single blue wire to 4.5" inches (115mm) in length.

Use wire strippers to remove a bit of insulation from the tips of each wire then apply a bit of solder to tin them.

Install Key Switches 

Snap the five CHOC key switches into the 3D printed key plate oriented as shown here.

Ensure all of the keys are installed in the same orientation.

Install Key Sockets

Remove the protective cover from the cut tape reel of key sockets.

Insert the key sockets into CHOC key switches being very careful not to bend the pins.

Solder Wires to Sockets

Use the short blue wires to connect ground pins together on the switches.

Use the white wires to connect to the signal pins on the switches.

Solder Wires to KB2040

Connect the signal wires from the switches to the GPIO pins on the KB2040.

• Key 1 to D4
• Key 2 to D5
• Key 3 to D6
• Key 4 to D7
• Key 5 to D8

Solder the long blue wire to GND on the KB2040.

Solder Wires to Rotary Encoder

Use black, blue, yellow, and white wires to create connections for the rotary encoder.

Cut black, blue, yellow, and white wires to 4 inches (102mm) in length. Then, create a shorter black wire (1.5in/38mm long).

Solder the two black wires to the ground encoder switch pin. Then, solder the shorter black wire to the middle pin of the rotary encoder.

Solder the blue wire to either the far left or right pin. Solder yellow wire to the remaining pin on the rotary encoder.

Rotary Encoder Wired

Double check the wires on the rotary encoder and ensure the wires have been properly soldered to the pins.

Optionally, use a piece of heat shrink tubing to keep the wires bundled together.

Wires for Potentiometers

Use green, black and red colored wires to create connections for the three potentiometers.

Make three green wires, a single black and red wire to be 4.4in (112mm) long.

Make two black and red wires to be 1.5in (38mm) long.

Optionally apply labels to the bottom of the potentiometers.

Solder Potentiometers

Start with the first potentiometer (A-A2) and solder a short and long black wire to the far left pin. Then, solder a longer green wire to the middle pin. Solder a short and long red wire to the remaining pin on the potentiometer.

Solder the short black wire from Potentiometer A along with a second short black wire to the far left pin on Potentiometer B. Solder a green wire to the middle pin. Solder the short red wire from Potentiometer A along with the second short red wire to the remaining pin.

Solder the short black wire from Potentiometer B to the far left pin on Potentiometer C. Solder the last green wire to the middle pin. Solder the short red wire from Potentiometer B to the remaining pin.

Wired Potentiometers

Take a moment to ensure all of the wires have been properly soldered to the pins on each potentiometer.

Optionally add a piece of heat shrink tubing to keep the wires bundled together.

Connect Rotary Encoder to KB2040

Solder the wires from the rotary encoder to the following pins on the KB2040.

• Black wire to Ground
• Blue wire to D2
• Yellow wire to D3
• White wire to A3

Double check all of the wires have been properly soldered to the correct pins on the KB2040.

Connect Pots to KB2040

Solder the wires from the potentiometers to the following pins on the KB2040

• Pot A green wire to A2
• Pot B green wire to A1
• Pot C green wire to A0
• Shared black wire to Ground
• Shared red wire to 3V

Double check all of the wires from the potentiometer have been properly soldered to the correct pins on the KB2040.