qmk_firmware/keyboards/handwired/6key/keymaps/via/keymap.c

 /* Copyright 2022 Bratzworth
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
#include QMK_KEYBOARD_H

const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
    [0] = LAYOUT(
        LCTL(KC_Z), LCTL(KC_Y), KC_A,
        KC_C,       KC_D,       KC_S
    ),
    [1] = LAYOUT(
        KC_F13, KC_F14, KC_F15,
        KC_F16, KC_F17, KC_F18
    ),
    [2] = LAYOUT(
        KC_TRNS, KC_TRNS, KC_TRNS,
        KC_TRNS, KC_TRNS, KC_TRNS
        ),
    [3] = LAYOUT(
        KC_TRNS, KC_TRNS, KC_TRNS,
        KC_TRNS, KC_TRNS, KC_TRNS
        ),
};