qmk_firmware/keyboards/niu_mini/niu_mini.h

#ifndef NIU_MINI_H
#define NIU_MINI_H

#include "quantum.h"

#define LAYOUT_mit( \
	k00, k01, k02, k03, k04, k05, k06, k07, k08, k09, k0a, k0b, \
	k10, k11, k12, k13, k14, k15, k16, k17, k18, k19, k1a, k1b, \
	k20, k21, k22, k23, k24, k25, k26, k27, k28, k29, k2a, k2b, \
	k30, k31, k32, k33, k34,    k35,   k37, k38, k39, k3a, k3b \
) \
{ \
	{ k00, k01, k02, k03, k04, k05, k06,   k07, k08, k09, k0a, k0b }, \
	{ k10, k11, k12, k13, k14, k15, k16,   k17, k18, k19, k1a, k1b }, \
	{ k20, k21, k22, k23, k24, k25, k26,   k27, k28, k29, k2a, k2b }, \
	{ k30, k31, k32, k33, k34, k35, KC_NO, k37, k38, k39, k3a, k3b } \
}

#define LAYOUT_grid( \
	k00, k01, k02, k03, k04, k05, k06, k07, k08, k09, k0a, k0b, \
	k10, k11, k12, k13, k14, k15, k16, k17, k18, k19, k1a, k1b, \
	k20, k21, k22, k23, k24, k25, k26, k27, k28, k29, k2a, k2b, \
	k30, k31, k32, k33, k34, k35, k36, k37, k38, k39, k3a, k3b \
) \
{ \
	{ k00, k01, k02, k03, k04, k05, k06, k07, k08, k09, k0a, k0b }, \
	{ k10, k11, k12, k13, k14, k15, k16, k17, k18, k19, k1a, k1b }, \
	{ k20, k21, k22, k23, k24, k25, k26, k27, k28, k29, k2a, k2b }, \
	{ k30, k31, k32, k33, k34, k35, k36, k37, k38, k39, k3a, k3b } \
}

#define LAYOUT LAYOUT_grid
#define LAYOUT_ortho_4x12 LAYOUT_grid

#endif