Pico Keyboard Rev.1

Pico Keyboard is designed for small hands.
It adopted the footprint for Kailh Mid-Height smaller than Cherry MX compatible switches.

Japanese Manual is here.

Summary

• Bill of materials
• Assembly guide
• Firmware
  • Basic compiling and burning command
  • First time burning
  • Burning keymap for 70 keys

Bill of materials

Qty	Item	Notes
2	Pico PCBs
65	1N4148 diodes	SMD diodes can also be used
2	PJ-320A 4 poles 3.5 mm TRRS connectors
2	4.7 kΩ resistors	Need to be soldered on one half only
2	Through hole momentary switch	Dimensions 6mm x 6mm x 4.3mm
2	Arduino Pro Micro	ATMega32U4
1	TRRS cable
1	USB micro cable
2	Cases
10	Screws	M3
10	Spacers	M3
8	Washers	M3 thickness 0.8mm
2	Nuts	M3 thickness 2.4mm
65	Kailh Mid-Height	Brown, Red or Blue.
65	Kailh Mid-Height compatible keycaps	65x 1u keycaps

It is possible to assembly Pico Keyboard as 70 keys keyboard. In this case, you need 70 each 1N4148 diodes, switches, keycaps.

Pico rev1 Basic is on sale at BOOTH (NOT including switches and keycaps).

mulgrey created Kailh Mid-Height compatible keycaps! Thanks 🎉
Thease are in DMM.make Creator's market.

• DMM.make > mini keycap 72 pieces
  

Assembly guide

Installation steps:

• Solder components on Mounting Surface side:
  1. Solder 1N4148 diodes. Keep the diode legs for the right hand controller installation.
     
     
  2. Solder PJ-320A connectors.
  3. Solder momentary switches.
  4. Solder 4.7 kΩ resistors on one half only.
  5. Solder the Pro Micro header pins (do not solder the Pro Micro controllers yet).
• Install upper cases to PCBs.
  • M3x10 screws → upper case → washers → PCB → spacers.
    
     
• Fit switches to the upper cases and solder to the PCB.
• Solder Pro Micros to the header pins.
  • Solder Pro Micro face down.
    
    

Firmware

Pico keyboard uses QMK Firmware for its firmware.
Follow the QMK installation instructions here, then compile and burn the firmware as follows:

Basic compiling and burning command

$ cd path/to/qmk_firmware
$ make pico/65keys:default:flash

※ If you burn a keymap for 70 keys, please see Burning keymap for 70 keys.

First time burning

You need to burn the firmware both left hand and right hand.

1. Left hand side

Edit pico/config.h and activate MASTER_LEFT .

/* Select hand configuration */
#define MASTER_LEFT
// #define MASTER_RIGHT
// #define EE_HANDS

Save the file, then connect Pro Micro(left hand) and your PC by USB cable.
Compile and burn the firmware by running Basic compiling and burning command as follows:

$ cd path/to/qmk_firmware
$ make pico/65keys:default:flash

2. Right hand side

Edit pico/config.h and activate MASTER_RIGHT .

/* Select hand configuration */
// #define MASTER_LEFT
#define MASTER_RIGHT
// #define EE_HANDS

Save the file, then connect Pro Micro(right hand) and your PC by USB cable.
Compile and burn the firmware by running Basic compiling and burning command.

3. Confirmation

Pull out the USB cable, then connect left hand and right hand by TRRS cable.
Plug in the Pro Micro (Master) the USB cable.

Burning keymap for 70 keys

Replace from 65keys to 70keys , and do the above 1 to 3.

$ cd path/to/qmk_firmware
$ make pico/70keys:default:flash

Layout

http://www.keyboard-layout-editor.com/

65 keys default

KLE Layout permalink

70 keys default

KLE Layout permalink