qmk-firmware/keyboards/dp60/keymaps/indicator
..
config.h
indicator.c
keymap.c
led_driver.c
readme.md
rules.mk

Indicator RGB leds support for the open source viper/eagle fr4 plate

Three wires need to be soldered:

B1 pin (SCLK at the board) to the plate's D pin

VCC to plate's V

GND to plate's G