qmk_firmware/keyboards/dz60/keymaps/iso_uk/keymap.c

#include QMK_KEYBOARD_H

// LAYERS
#define _QWERTY 0      // QWERTY layer
#define _QW _QWERTY

#define _FUNCTION 1    // Function layer
#define _FN _FUNCTION

#define _CONTROL 2     // Control layer
#define _CN _CONTROL

// KEYCODES
#define _______ KC_TRNS
#define XXXXXXX KC_NO

#define MO_FN MO(1)
#define MO_FN MO(1)
#define MO_FN MO(1)

#define MODS_CTRL_MASK  (MOD_BIT(KC_LSHIFT)|MOD_BIT(KC_RSHIFT))

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

  [_QWERTY] = LAYOUT_60_iso(
    //       2        3        4        5        6        7        8        9        10       11       12       13       14       15       16
    KC_GESC, KC_1,    KC_2,    KC_3,    KC_4,    KC_5,    KC_6,    KC_7,    KC_8,    KC_9,    KC_0,    KC_MINS, KC_EQL,  KC_BSPC,
    KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_LBRC, KC_RBRC,
    KC_CAPS, KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT, KC_NUHS, KC_ENT,
    KC_LSFT, KC_NUBS, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, KC_RSFT,
    KC_LCTL, KC_LGUI, KC_LALT,                   KC_SPC,                             KC_RALT, KC_RGUI, MO(_FN), KC_RCTL
  ),

  [_FUNCTION] = LAYOUT_60_iso(
    //       2        3        4        5        6        7        8        9        10       11       12       13       14       15       16
    KC_GRV,  KC_F1,   KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   KC_F7,   KC_F8,   KC_F9,   KC_F10,  KC_F11,  KC_F12,  KC_DEL,
    _______, KC_CALC, KC_UP,   _______, _______, _______, KC_INS,  KC_HOME, KC_UP,   KC_END,  KC_PGUP, KC_PSCR, KC_PAUS,
    _______, KC_LEFT, KC_DOWN, KC_RGHT, _______, _______, KC_DEL,  KC_LEFT, KC_DOWN, KC_RGHT, KC_PGDN, _______, _______, _______,
    _______, _______, _______, KC_APP,  _______, _______, _______, _______, KC_MUTE, KC_VOLD, KC_VOLU, _______, _______,
    _______, _______, _______,                   TG(_CN),                            _______, _______, _______, _______
  ),

  [_CONTROL] = LAYOUT_60_iso(
    //       2        3        4        5        6        7        8        9        10       11       12       13       14       15       16
    TG(_CN), _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, RESET,
    _______, RGB_MOD, RGB_HUI, RGB_SAI, RGB_VAI, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, RGB_TOG, RGB_HUD, RGB_SAD, RGB_VAD, _______, _______, _______, _______, _______, _______, _______, _______, _______,
    _______, _______, BL_DEC,  BL_TOGG, BL_INC,  BL_STEP, _______, _______, _______, _______, _______, _______, _______,
    _______, _______, _______,                   XXXXXXX,                            _______, _______, _______, _______
  ),

};

enum function_id {
    SHIFT_ESC,
};

const uint16_t PROGMEM fn_actions[] = {
  [0]  = ACTION_FUNCTION(SHIFT_ESC),
};

void action_function(keyrecord_t *record, uint8_t id, uint8_t opt) {
  static uint8_t shift_esc_shift_mask;
  switch (id) {
    case SHIFT_ESC:
      shift_esc_shift_mask = get_mods()&MODS_CTRL_MASK;
      if (record->event.pressed) {
        if (shift_esc_shift_mask) {
          add_key(KC_GRV);
          send_keyboard_report();
        } else {
          add_key(KC_ESC);
          send_keyboard_report();
        }
      } else {
        if (shift_esc_shift_mask) {
          del_key(KC_GRV);
          send_keyboard_report();
        } else {
          del_key(KC_ESC);
          send_keyboard_report();
        }
      }
      break;
  }
}