qmk-firmware/keyboards/ckeys/handwire_101/handwire_101.h

#pragma once

#include "quantum.h"

// This a shortcut to help you visually see your layout.
// The following is an example using the Planck MIT layout
// The first section contains all of the arguements
// The second converts the arguments into a two-dimensional array
#define LAYOUT( \
    k00, k01, k02, k03, \
    k10, k11, k12, k13, \
    k20, k21, k22, k23, \
    k30, k31, k32, k33 \
) \
{ \
    { k00, k01, k02, k03 }, \
    { k10, k11, k12, k13 }, \
    { k20, k21, k22, k23 }, \
    { k30, k31, k32, k33 } \
}