This repository contains a project to create a modern replacement PCB for Apple Lisa keyboards.
The Apple Lisa used a Keytronic foam and foil keyboard which is notorious for the foam turning to dust rendering the keyboard unusable. Even after replacing the foam, I was unable to get my Lisa keyboard fully working, so instead I created a replacement PCB so I could use modern keyswitches.
This repository is still a work in progress. The timing on the keyboard controller code still needs adjusting, and the PCB may require further revisions. For example, I only recently added stabilizers to the board. If you downloaded the PCB designs before 28 November 2023, you will want to download them again to get stabilizers and a better fitting PCB. Otherwise your keys won't be stable and you'll need to expand some of the holes with a Dremel.
- 76x Cherry MX compatible keyswitches
- 76x through-hole 1N4148 diodes
- 1x through-hole 3mm LED
- 1x through-hole 150 ohm resistor
- 2x through-hole 3-pin 2.54mm-spacing male headers
- 2x through-hole 14-pin 2.54mm-spacing male headers
- 1x through-hole 5-pin 2.54mm-spacing male header
- 1x Adafruit ItsyBitsy 32u4 5V microcontroller
- 1x 2-pin jumper
- 6x 2u stabilizers
- 1x 6.5u stabilizer (good luck; you will most likely need to get a 7u stabilizer and shorten it)
- 1x keyboard matrix PCB, made from the Gerber files in the
gerberdirectory - 4x mounting brackets, 3D printed from the STL file in the
mounting-bracketdirectory - a set of keycaps, made from the templates in the
keycapsdirectory (more details needed)- The hardest to get will be the 6.5u spacebar and the 1.5u backspace. Max Keyboards will make custom sets with a 6.5u spacebar. I haven't found a source for 1.5u backspace yet. You can use a 1.5u backslash key, but the profile will be wrong.
- You will need a 1u backslash key.
- The 1.75u return key can be made from a 1.75u caps lock key.
- You will need two 2.25u shift keys instead of a 2.25u shift key and a 2.75u shift key.
- For the bottom row, in addition to the 6.5u spacebar, you will need two 1u option keys, a 2u command key, and a 2u enter key. (The original keyboard had 1.5u command and enter keys and a 7.5u spacebar, but I shortened the spacebar to at least something obtainable.)
- Instead of num lock, /, *, -, and 2u tall +, the Lisa has clear, -, +, *, /, and comma, all 1u. Additionally, the +, *, /, and comma keys have a unique style of directional arrows on the bottom half of the key.
- Program the ItsyBitsy microcontroller with the Arduino sketch in the
lisakeysplusdirectory - Solder in the diodes first
- Solder in the LED in the desired location near the caps lock key
- Solder in the resistor and headers
- Solder in the ItsyBitsy microcontroller
- Solder in the keyswitches last
- Add the jumper between VCC and TIP on the header above the microcontroller
- Attach the stabilizers
- Install the keycaps
- Install the four mounting brackets in the bottom of the keyboard case
- Attach the keyboard cable to the header on the top left of the board
- Assemble the keyboard case