qmk_firmware/keyboards/ckeys/obelus/obelus.c

#include "quantum.h"

void matrix_init_kb(void) {
	// put your keyboard start-up code here
	// runs once when the firmware starts up
	// Turn status LED on
	gpio_set_pin_output(D6);
	gpio_write_pin_high(D6);

	matrix_init_user();
}