qmk_firmware/keyboards/handwired/zeropad/keymaps/default/keymap.c

// Copyright 2023 QMK
// SPDX-License-Identifier: GPL-2.0-or-later

#include QMK_KEYBOARD_H

const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {

    [0] = LAYOUT_ortho_3x3(
        KC_1,   KC_2,   KC_3,
        KC_4,   KC_5,   KC_6, 
        KC_7,   KC_8,   KC_9
    )
};