Pico42: Simple Hand-Solderable PCB in BM40/JJ40 Form-Factor, rev 2023.1

Pico42: Simple Hand-Solderable PCB in BM40/JJ40 Form-Factor

A very simple, hand-solderable PCB which uses the Raspberry Pi Pico dev board.

I made this design because in my first attempt at designing a CNC case for the PyKey40,
I put the cutout for the USB connector in the wrong place.
Having a design which doesn't use a USB connector underneath the PCB works around this.

The form factor encourages the thumbs to use 2-3 keys each (and rely on the pinky fingers less).

Design goals:

• Simple, hand-solderable PCB.

• Uses Raspberry Pi Pico devboard. / Doesn't use USB connector underneath PCB.

• Same mounting holes as JJ40/BM40/PyKey40.

• Same pinout as PyKey40 (PyKey60).

Pictures:

Pico42 PCB assembled with MX switches, in a low profile aluminium case.

Height of the Pico mounted on round-pin male headers in female headers.

Pico42 PCB assembled with Kailh Choc switches, in a sandwich case.

Underside of the Pico42 in a sandwich style case.

2D Renders of the PCB, revision rev2023.1

Build Guides

• rev2023.1 Interactive BOM

• rev2023.1 Build Guide Notes

Release Assets

• DXF/SVG Plates:

  • Take care with DXF files. DXF files don't have units. Different programs might make different assumptions about the plate size. (Should be 230.5x77.5mm, or 227x75mm for the _pcb files).
  • The _pcb DXF/SVG is for cutting a bottom plate that aligns with the PCB. This is useful for a plate-less build.

• Firmware:

  • rgoulter_pico42_default.uf2 provides a keymap where every key is assigned. This is useful to check that each key works, using a keyboard tester like QMK Configurator, although this keymap is not practical for any more than that.
  • rgoulter_pico42_manna-harbour_miryoku.uf2 provides a split_3x5_3 build of the Miryoku layout. See Miryoku Reference. This uses the default Colmak Mod-DH as its base layer, and QWERTY as its extra keymap (c.f. Miryoku's Additional Features).