kevin-nel / pico-dactyl

a work in progress corne inspired dactyl manuform style keyboard with addressible rgb leds using the raspberry pi pico and an io expander and KMK firmware

PicoDactyl

THIS HAS BEEN ARCHIVED I am leaving this here because it has a pretty decent readme with the thought process for desighning a handware that I will probably want to come back to. I printed half the dactyl and then realised i do not like how it feels.

inspiration:

hardware

The following are links to purchase hardware at microrobotics.org.za. If you are not located in South Africa you should use your own local electronics store.

• rpi pico
  • datasheet
• pcf8575
  • python library
  • datasheet
  • check this example firmware which uses a different i2c expander chip
    • mcp23017 io expander (out of stock at time of planning)
      • datasheet
      • example circuit
      • another example schematic
• rj 45 connectors
  • provides up to eight wires
• usb B printer cable
• EC11 rotary encoder
• M3 brass heat set inserts
• cherry mx brown switches (salvaged from another keyboard)

design

• minidox/corne/reviung inspired design
  • 3x6 for main clusters
  • 3/4 keys per hand for thumb cluster
    • can therefore use 2 3x7 matrices and use the rj45 connector for scl/sda/vbus/gnd/v+
  • rotary encoder on one half
  • rgb leds (ws2812 rings from banggood)
    • need 1 data pin (din), power and ground (check pico datasheet for whether to use vbus or vdd!)
  • printed in transparent (translucent) PLA
    • print time is estimated 18 hours per side (excluding bottom plate)
  • will need to design inserts for the rj45 connectors and for the usb B adaptor as well as the pi pico holder
    • loligag sled format
      • example
    • wally plate gen
  • will also need to design holder for led rings (probably on the base plate)
  • holder for the pi pico and the io expander
    • this on from printables.com
  • use this converter to mount an ec11 encoder in an mx socket.

I used this dactyl case generator that uses open cascade and generates much neater models (cleaner stls).

• see run_config.json for my config used to generate the case
• installation was fairly simple:
  1. install docker desktop
  2. download the dactyl case generator repo
  3. run the build_docker.bat script.
  4. in docker desktop open the DM-shell container in terminal and run bash
  5. run generate_configuration.py
  6. edit src/run_config.json (don't forget to save)
  7. run python3 dactyl_manuform.py
  8. open things/DM_left.scad and preview it in openSCAD
  9. repeat steps 6-8 until happy with the case.
  10. compile the case files in openSCAD and export the stls

my tweaks were:

• 3x6 design with 3 keys on each thumb cluster
• remove oled clips (use null)
• make screw posts larger to fit my inserts
• import into tinkercad to make holes for the connectors and attach mounts for the controller boards
• cleanup mesh in blender (some of the screw posts were sticking through the outside of the case).

edit: Custom case?

I am currently working on a custom dactylesqu case inspired by the skeletyl. I want to try to close all the gaps without making it look spikey. Doing it from scratch will also make the connectors a bit more polished than my attempts at hacking together stls in tinkercad. I am using onShape for the time being and it is my first time actually using a real cad package so this might take a while.

firmware

IO expander:

• some example firmware using an IO expander
• more example firmware with pcf8575 (commented out)
• adafruit pcf8575 example
• adafruit circuit python module for the pcf8575

Pi Pico

• mostly just going to try KMK there are lots of examples

construction

• do columns/rows and diodes first
• attach connectors and micros
• measure out the length of wire to connect rows and columns
• connect rows/cols to the micros and connectors
• hotglue any switches/components that are not fitting tightly

circuit diagram:

references