neilkatahira/handwired_preonic

QMK based 5x12 ortholinear keyboard

Handwired 5x12 Ortholinear Keyboard

This repo contains layout-specific files and a build log for an Atmel-AVR based handwired 50% ortholinear keyboard similar to the Preonic. Keyboard firmware used is the open-source QMK, maintained by Jack Humbert of OLKB along with the MK community.

BOM

• 1x Pro Micro 5V 16MHz
• 1x set Preonic Plate + Case
• 60x Switches (used Outemu Ice V2)
• 60x 1N4148 Diodes
• Wires (used 22AWG solid core)
• 10x M2 6mm screws
• 5x M2 Female Brass Standoffs 12mm
• 1x Micro USB Cable
• 1x Keycap set

Additional Tools

• Ender 3 Pro
• Station 60 Soldering Station
• Kester 44 63/37 Solder
• Overture Black + Overture Orange PLA Filament
• Multimeter
• Klein Tools Wire Stripper/Cutter
• Flush Cutter
• Screwdriver
• Hot Glue / Superglue
• Heat Gun / Lighter

Assembly

1. 3D print or source out case and switch plate. If 3D printing, making the plate thicker to reduce flexing is recommended.

2. Loop anode end (non-black line side) of 1N4148 diode to one leg of the switch as shown. Solder, and repeat for all switches. Solder cathode ends (black line side) together to form diode rows. Check for continuity from end to end.

3. Solder column wires as shown to other leg of the switches. Keeping insulation between connections is recommended. Check for continuity from top row switch leg to bottom row switch leg for each column.

4. Pick 17 I/O pins on Pro Micro for each row and column. Pro Micro pinout information can be found on Deskthority. Measure leads to respectable lengths, then cut and solder onto microcontroller board.

5. Solder wires created in step 4 to each row and column. Test each connection for continuity.

6. Follow QMK's environment setup and firmware building tutorial.
7. If new to QMK, setup basic firmware structure for handwired builds in QMK's handwiring guide.
8. Setup keyboard layers as desired. Use Keyboard Layout Editor, QMK Configurator, and QMK basic keycodes as help.
9. In config.h, change MATRIX_ROWS, MATRIX_COLS, MATRIX_ROW_PINS, and MATRIX_COL_PINS as wired.
10. Short GND and RST to bring the Pro Micro into bootloader mode.
11. Use QMK Toolbox or other methods listed in the QMK flashing guide to flash the bootloader.
12. Use QMK Keyboard Tester to test if each key works as intended. If a key does not work, check wiring for continuity, switches if working, and code.
13. Once working, prepare case by screwing in M2 screws from below to brass standoffs inside.
14. Place plate into case, lining up Pro Micro to port hole in the rear of the case. Screw M2 screws to secure plate.

15. Place keycaps onto switches.

References

• Pro Micro Information
• QMK Toolbox
• QMK Configurator
• KB Firmware Builder
• Keyboard Layout Editor
• In-depth Handwiring Guide
• How to Handwire a Planck
• How a Keyboard Matrix Works
• Keyboard Matrix Scanning