Egg58v2

egg58

The egg58 is a staggered-column, split, low-profile keyboard with 58 keys and per-key RGB. The PCB is reversible (i.e. the same part is used for both hands). This repository contains its design files.

Layout

The egg58 was designed to remain fairly close in layout to an ANSI 60% keyboard, but with a reduced number of keys and minimal thumb clusters.

This is a suggested layout, but obviously it is customizable.

Original variant

The original (wired) keyboard design files can be found in directory egg58v2.

Materials

• 2x PCB (from this repo)
• 2x switchplate (from this repo)
• 2x Pro Micro or Elite-C
• 2x 4.7K through hole resistors (for I2C option)
• 2x 3.5mm TRRS jack (PJ-320A)
• 58 Choc sockets
• 58 Choc switches (Choc V1 only)
• 58 diodes (1N4148 or similar, throughhole or SOD123)
• 58 SK6812 Mini-E LEDs
• 1x TRRS cable

Build instructions

On the back of each board:

• Install LEDs such that the notched corner aligns with the indicator on the silkscreen.
  • Be aware that the orientation of the LEDs changes each row.
• Install diodes, such that the cathode (the side with the line) points toward the square holes (upward).
  • If using through-hole diodes with the FR4 switchplate, ensure that the leads are trimmed very short on the front, otherwise they may scratch through the switchplate solder mask and short out.
• Install sockets.
• If I2C is being used, install the two resistors beneath the location for the TRRS. (They can be placed on the front instead if desired.)
  • Recommended to use either 2x 4.7K on a single hand, or 4x 10K on both hands.
  • The values are fairly flexible, as long as the total resistance on each line is between 2.2K-10K.
• Solder the two jumpers to select serial/I2C and Elite-C/Pro Micro.
  • The EliteC/ProMicro jumper selects the position of the VBUS/RAW pin, to supply 5v to the LEDs and across the TRRS cable. On the Elite-C, the RAW pin is replaced with an extra I/O pin (B0) and an extra VBUS pin is added above it. Select EliteC in this case, or ProMicro for all others.
  • The Serial/I2C jumper selects which data pin is attached to the TRRS jack. The firmware uses I2C by default, but select Serial if you have customized it.
  • Each jumper should have one "outer" pad soldered to the inner pad. See Issue #4 for further explanation and a diagram.

On the front:

• Install TRRS.
• Install MCU (preferably in a socket).

Mount the switchplate to the PCB with 5x M2 screws. Nylon screws are recommended. A spacer is recommended between the two layers. Finally, install switches in the sockets.

Firmware

My fork of QMK contains default configuration and a keymap for the board.

The configuration will need to be changed if using soft serial instead of I2C, or if your microcontrollers do not use the DFU bootloader.

Changelog

Revision 2.1 - 2023-04-01

• Add support for VBUS from Elite-C

Revision 2.0 - 2022-03-04

• Original Chocs are used rather than Choc v2
• There is an option to use soft serial instead of I2C for the bridge transport
• The Elite-C microcontroller is now supported in addition to the Pro Micro
• The LEDs are now north-facing (since that is more suitable for the only shine-through caps for Choc currently available)
• The thumb cluster is now designed for 2x 1.5u instead of one 1.5u and one 2u key
• Keys now use Choc spacing instead of MX (be aware of this when purchasing keycaps)

Wireless variant

A simplified version designed to be used with ZMK is available in the egg58bt directory. This version has no RGB and uses BLE for both connectivity to the host and the split transport.

Materials

• 2x PCB (from this repo)
• 2x switchplate (from this repo)
• 2x nice!nano microcontrollers
• 58 Choc sockets
• 58 Choc switches (Choc V1 only)
• 58 diodes (1N4148 or similar, throughhole or SOD123)

Build instructions

Construction is the same as the original variant above, just skip the steps related to the split transport and LEDs.

Firmware

ZMK support is available from my zmk-config repo.

Changelog

2023-02-20

• Created wireless variant

Accessories

A 3D-printable case compatible with both the original and wireless boards can be found in egg58v2 case. The case uses M2 threaded heat-set inserts to mount the board.

Minimal tenting stands in 15, 10, and 5 degree variants can be printed from the models in egg58v2 tenting stands. They also use M2 threaded inserts. The tenting stands are mutually exclusive with the full-bottom case. Rubber bumpons should be applied to the bottom of the stands, and on the "outside" edge of the PCB where the stands do not attach.

A model for a wrist rest is also available in egg58v2 wrist rest.

License

This repository is available under the terms of the GPL, verison 3.

Some portions are derived from:

• keyswitches.pretty (CC BY-SA 4.0)
• Keebio-Parts.pretty (MIT)
• ProMicroKiCad (MIT)
• SofleKeyboard (MIT)