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0xB2 - splinky controller

0xB2 - splinky is a Pro-Micro/Elite-C replacement development board by plut0nium – with USB-C and RP2040.
Published July 24, 2022

Designed for use in custom mechanical (split) keyboards, 0xB2 - splinky is an open-hardware development board designed and shared by Charles aka plut0nium.


  • Pro Micro / Sparkfun RP2040 compatible footprint with 5 extra pins (GPIO12..16) at bottom a la Elite-C
  • Raspberry Pi RP2040 MCU
  • Up to 16MB flash memory (depending on component selection and availability)
  • User LED & USB VBUS detect (GPIO19)
  • Low profile USB-C mid-mount connector
  • Designed to be manufactured and assembled by all common PCBA services

This pinout is a de facto standard, established by actors of the MK community (see discussions in #RP2040 on the bastardkb Discord server) – Charles.


GitHub repo with required information (gerbers, bom, pos) for assembly e.g. by JLCPCB.:

(Thanks for the tip Quentin!)

Published on Sun 24th Jul 2022. Featured in KBD #88 (source).

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