diff --git a/common.mk b/common.mk
index be9f289c..6759e6ef 100644
--- a/common.mk
+++ b/common.mk
@@ -5,7 +5,7 @@ SRC +=	$(COMMON_DIR)/host.c \
 	$(COMMON_DIR)/action_tapping.c \
 	$(COMMON_DIR)/action_oneshot.c \
 	$(COMMON_DIR)/action_macro.c \
-	$(COMMON_DIR)/layer_switch.c \
+	$(COMMON_DIR)/action_layer.c \
 	$(COMMON_DIR)/keymap.c \
 	$(COMMON_DIR)/timer.c \
 	$(COMMON_DIR)/print.c \
diff --git a/common/action.c b/common/action.c
index 07a3a64d..06518874 100644
--- a/common/action.c
+++ b/common/action.c
@@ -21,7 +21,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "command.h"
 #include "debug.h"
 #include "led.h"
-#include "layer_switch.h"
+#include "action_layer.h"
 #include "action_tapping.h"
 #include "action_oneshot.h"
 #include "action_macro.h"
@@ -50,15 +50,19 @@ void action_exec(keyevent_t event)
 void process_action(keyrecord_t *record)
 {
     keyevent_t event = record->event;
+#ifndef NO_ACTION_TAPPING
     uint8_t tap_count = record->tap.count;
+#endif
 
     if (IS_NOEVENT(event)) { return; }
 
     action_t action = layer_switch_get_action(event.key);
     debug("ACTION: "); debug_action(action);
-    debug(" overlays: "); overlay_debug();
-    debug(" keymaps: "); keymap_debug();
-    debug(" default_layer: "); debug_dec(default_layer); debug("\n");
+#ifndef NO_ACTION_LAYER
+    debug(" layer_state: "); layer_debug();
+    debug(" default_layer_state: "); default_layer_debug();
+#endif
+    debug("\n");
 
     switch (action.kind.id) {
         /* Key and Mods */
@@ -68,22 +72,17 @@ void process_action(keyrecord_t *record)
                 uint8_t mods = (action.kind.id == ACT_LMODS) ?  action.key.mods :
                                                                 action.key.mods<<4;
                 if (event.pressed) {
-                    uint8_t tmp_mods = host_get_mods();
                     if (mods) {
                         host_add_mods(mods);
                         host_send_keyboard_report();
                     }
                     register_code(action.key.code);
-                    if (mods && action.key.code) {
-                        host_set_mods(tmp_mods);
-                        host_send_keyboard_report();
-                    }
                 } else {
-                    if (mods && !action.key.code) {
+                    unregister_code(action.key.code);
+                    if (mods) {
                         host_del_mods(mods);
                         host_send_keyboard_report();
                     }
-                    unregister_code(action.key.code);
                 }
             }
             break;
@@ -93,7 +92,7 @@ void process_action(keyrecord_t *record)
             {
                 uint8_t mods = (action.kind.id == ACT_LMODS_TAP) ?  action.key.mods :
                                                                     action.key.mods<<4;
-                switch (action.layer.code) {
+                switch (action.layer_tap.code) {
     #ifndef NO_ACTION_ONESHOT
                     case 0x00:
                         // Oneshot modifier
@@ -199,323 +198,88 @@ void process_action(keyrecord_t *record)
             }
             break;
 #endif
-#ifndef NO_ACTION_KEYMAP
-        case ACT_KEYMAP:
-            switch (action.layer.code) {
-                /* Keymap clear */
-                case OP_RESET:
-                    switch (action.layer.val & 0x03) {
-                        case 0:
-                            // NOTE: reserved
-                            overlay_clear();
-                            keymap_clear();
-                            break;
-                        case ON_PRESS:
-                            if (event.pressed) {
-                                overlay_clear();
-                                keymap_clear();
-                            }
-                            break;
-                        case ON_RELEASE:
-                            if (!event.pressed) {
-                                overlay_clear();
-                                keymap_clear();
-                            }
-                            break;
-                        case ON_BOTH:
-                            overlay_clear();
-                            keymap_clear();
-                            break;
-                        /* NOTE: 4-7 rserved */
+#ifndef NO_ACTION_LAYER
+        case ACT_LAYER:
+            if (action.layer_bitop.on == 0) {
+                /* Default Layer Bitwise Operation */
+                if (!event.pressed) {
+                    uint8_t shift = action.layer_bitop.part*4;
+                    uint32_t bits = ((uint32_t)action.layer_bitop.bits)<<shift;
+                    uint32_t mask = (action.layer_bitop.xbit) ? ~(((uint32_t)0xf)<<shift) : 0;
+                    switch (action.layer_bitop.op) {
+                        case OP_BIT_AND: default_layer_and(bits | mask); break;
+                        case OP_BIT_OR:  default_layer_or(bits | mask);  break;
+                        case OP_BIT_XOR: default_layer_xor(bits | mask); break;
+                        case OP_BIT_SET: default_layer_and(mask); default_layer_or(bits); break;
                     }
-                    break;
-                /* Keymap Reset default layer */
-                case (OP_RESET | ON_PRESS):
-                    if (event.pressed) {
-                        default_layer_set(action.layer.val);
+                }
+            } else {
+                /* Layer Bitwise Operation */
+                if (event.pressed ? (action.layer_bitop.on & ON_PRESS) :
+                                    (action.layer_bitop.on & ON_RELEASE)) {
+                    uint8_t shift = action.layer_bitop.part*4;
+                    uint32_t bits = ((uint32_t)action.layer_bitop.bits)<<shift;
+                    uint32_t mask = (action.layer_bitop.xbit) ? ~(((uint32_t)0xf)<<shift) : 0;
+                    switch (action.layer_bitop.op) {
+                        case OP_BIT_AND: layer_and(bits | mask); break;
+                        case OP_BIT_OR:  layer_or(bits | mask);  break;
+                        case OP_BIT_XOR: layer_xor(bits | mask); break;
+                        case OP_BIT_SET: layer_and(mask); layer_or(bits); break;
                     }
-                    break;
-                case (OP_RESET | ON_RELEASE):
-                    if (!event.pressed) {
-                        default_layer_set(action.layer.val);
-                    }
-                    break;
-                case (OP_RESET | ON_BOTH):
-                    default_layer_set(action.layer.val);
-                    break;
-
-                /* Keymap Bit invert */
-                case OP_INV:
-                    /* with tap toggle */
+                }
+            }
+            break;
+    #ifndef NO_ACTION_TAPPING
+        case ACT_LAYER_TAP:
+        case ACT_LAYER_TAP1:
+            switch (action.layer_tap.code) {
+                case OP_TAP_TOGGLE:
+                    /* tap toggle */
                     if (event.pressed) {
                         if (tap_count < TAPPING_TOGGLE) {
-                            debug("KEYMAP_INV: tap toggle(press).\n");
-                            keymap_invert(action.layer.val);
+                            layer_invert(action.layer_tap.val);
                         }
                     } else {
                         if (tap_count <= TAPPING_TOGGLE) {
-                            debug("KEYMAP_INV: tap toggle(release).\n");
-                            keymap_invert(action.layer.val);
+                            layer_invert(action.layer_tap.val);
                         }
                     }
                     break;
-                case (OP_INV | ON_PRESS):
-                    if (event.pressed) {
-                        keymap_invert(action.layer.val);
-                    }
+                case OP_ON_OFF:
+                    event.pressed ? layer_on(action.layer_tap.val) :
+                                    layer_off(action.layer_tap.val);
                     break;
-                case (OP_INV | ON_RELEASE):
-                    if (!event.pressed) {
-                        keymap_invert(action.layer.val);
-                    }
+                case OP_OFF_ON:
+                    event.pressed ? layer_off(action.layer_tap.val) :
+                                    layer_on(action.layer_tap.val);
                     break;
-                case (OP_INV | ON_BOTH):
-                    keymap_invert(action.layer.val);
+                case OP_SET_CLEAR:
+                    event.pressed ? layer_move(action.layer_tap.val) :
+                                    layer_clear();
                     break;
-
-                /* Keymap Bit on */
-                case OP_ON:
-                    if (event.pressed) {
-                        keymap_on(action.layer.val);
-                    } else {
-                        keymap_off(action.layer.val);
-                    }
-                    break;
-                case (OP_ON | ON_PRESS):
-                    if (event.pressed) {
-                        keymap_on(action.layer.val);
-                    }
-                    break;
-                case (OP_ON | ON_RELEASE):
-                    if (!event.pressed) {
-                        keymap_on(action.layer.val);
-                    }
-                    break;
-                case (OP_ON | ON_BOTH):
-                    keymap_on(action.layer.val);
-                    break;
-
-                /* Keymap Bit off */
-                case OP_OFF:
-                    if (event.pressed) {
-                        keymap_off(action.layer.val);
-                    } else {
-                        keymap_on(action.layer.val);
-                    }
-                    break;
-                case (OP_OFF | ON_PRESS):
-                    if (event.pressed) {
-                        keymap_off(action.layer.val);
-                    }
-                    break;
-                case (OP_OFF | ON_RELEASE):
-                    if (!event.pressed) {
-                        keymap_off(action.layer.val);
-                    }
-                    break;
-                case (OP_OFF | ON_BOTH):
-                    keymap_off(action.layer.val);
-                    break;
-
-                /* Keymap Bit set */
-                case OP_SET:
-                    if (event.pressed) {
-                        keymap_set(action.layer.val);
-                    } else {
-                        keymap_clear();
-                    }
-                    break;
-                case (OP_SET | ON_PRESS):
-                    if (event.pressed) {
-                        keymap_set(action.layer.val);
-                    }
-                    break;
-                case (OP_SET | ON_RELEASE):
-                    if (!event.pressed) {
-                        keymap_set(action.layer.val);
-                    }
-                    break;
-                case (OP_SET | ON_BOTH):
-                    keymap_set(action.layer.val);
-                    break;
-
-                /* Keymap Bit invert with tap key */
                 default:
+                    /* tap key */
                     if (event.pressed) {
                         if (tap_count > 0) {
                             debug("KEYMAP_TAP_KEY: Tap: register_code\n");
-                            register_code(action.layer.code);
+                            register_code(action.layer_tap.code);
                         } else {
                             debug("KEYMAP_TAP_KEY: No tap: On on press\n");
-                            keymap_on(action.layer.val);
+                            layer_on(action.layer_tap.val);
                         }
                     } else {
                         if (tap_count > 0) {
                             debug("KEYMAP_TAP_KEY: Tap: unregister_code\n");
-                            unregister_code(action.layer.code);
+                            unregister_code(action.layer_tap.code);
                         } else {
                             debug("KEYMAP_TAP_KEY: No tap: Off on release\n");
-                            keymap_off(action.layer.val);
-                        }
-                    }
-                    break;
-            }
-            break;
-#endif
-#ifndef NO_ACTION_OVERLAY
-        case ACT_OVERLAY:
-            switch (action.layer.code) {
-                // Overlay Invert bit4
-                case OP_INV4 | 0:
-                    if (action.layer.val == 0) {
-                        // NOTE: reserved for future use
-                        overlay_clear();
-                    } else {
-                        overlay_set(overlay_stat ^ action.layer.val);
-                    }
-                    break;
-                case OP_INV4 | 1:
-                    if (action.layer.val == 0) {
-                        // on pressed
-                        if (event.pressed) overlay_clear();
-                    } else {
-                        overlay_set(overlay_stat ^ action.layer.val<<4);
-                    }
-                    break;
-                case OP_INV4 | 2:
-                    if (action.layer.val == 0) {
-                        // on released
-                        if (!event.pressed) overlay_clear();
-                    } else {
-                        overlay_set(overlay_stat ^ action.layer.val<<8);
-                    }
-                    break;
-                case OP_INV4 | 3:
-                    if (action.layer.val == 0) {
-                        // on both
-                        overlay_clear();
-                    } else {
-                        overlay_set(overlay_stat ^ action.layer.val<<12);
-                    }
-                    break;
-
-                /* Overlay Bit invert */
-                case OP_INV:
-                    /* with tap toggle */
-                    if (event.pressed) {
-                        if (tap_count < TAPPING_TOGGLE) {
-                            debug("OVERLAY_INV: tap toggle(press).\n");
-                            overlay_invert(action.layer.val);
-                        }
-                    } else {
-                        if (tap_count <= TAPPING_TOGGLE) {
-                            debug("OVERLAY_INV: tap toggle(release).\n");
-                            overlay_invert(action.layer.val);
-                        }
-                    }
-                    break;
-                case (OP_INV | ON_PRESS):
-                    if (event.pressed) {
-                        overlay_invert(action.layer.val);
-                    }
-                    break;
-                case (OP_INV | ON_RELEASE):
-                    if (!event.pressed) {
-                        overlay_invert(action.layer.val);
-                    }
-                    break;
-                case (OP_INV | ON_BOTH):
-                    overlay_invert(action.layer.val);
-                    break;
-
-                /* Overlay Bit on */
-                case OP_ON:
-                    if (event.pressed) {
-                        overlay_on(action.layer.val);
-                    } else {
-                        overlay_off(action.layer.val);
-                    }
-                    break;
-                case (OP_ON | ON_PRESS):
-                    if (event.pressed) {
-                        overlay_on(action.layer.val);
-                    }
-                    break;
-                case (OP_ON | ON_RELEASE):
-                    if (!event.pressed) {
-                        overlay_on(action.layer.val);
-                    }
-                    break;
-                case (OP_ON | ON_BOTH):
-                    overlay_on(action.layer.val);
-                    break;
-
-                /* Overlay Bit off */
-                case OP_OFF:
-                    if (event.pressed) {
-                        overlay_off(action.layer.val);
-                    } else {
-                        overlay_on(action.layer.val);
-                    }
-                    break;
-                case (OP_OFF | ON_PRESS):
-                    if (event.pressed) {
-                        overlay_off(action.layer.val);
-                    }
-                    break;
-                case (OP_OFF | ON_RELEASE):
-                    if (!event.pressed) {
-                        overlay_off(action.layer.val);
-                    }
-                    break;
-                case (OP_OFF | ON_BOTH):
-                    overlay_off(action.layer.val);
-                    break;
-
-                /* Overlay Bit set */
-                case OP_SET:
-                    if (event.pressed) {
-                        overlay_move(action.layer.val);
-                    } else {
-                        overlay_clear();
-                    }
-                    break;
-                case (OP_SET | ON_PRESS):
-                    if (event.pressed) {
-                        overlay_move(action.layer.val);
-                    }
-                    break;
-                case (OP_SET | ON_RELEASE):
-                    if (!event.pressed) {
-                        overlay_move(action.layer.val);
-                    }
-                    break;
-                case (OP_SET | ON_BOTH):
-                    overlay_move(action.layer.val);
-                    break;
-
-                /* Overlay Bit invert with tap key */
-                default:
-                    if (event.pressed) {
-                        if (tap_count > 0) {
-                            debug("OVERLAY_TAP_KEY: Tap: register_code\n");
-                            register_code(action.layer.code);
-                        } else {
-                            debug("OVERLAY_TAP_KEY: No tap: On on press\n");
-                            overlay_on(action.layer.val);
-                        }
-                    } else {
-                        if (tap_count > 0) {
-                            debug("OVERLAY_TAP_KEY: Tap: unregister_code\n");
-                            unregister_code(action.layer.code);
-                        } else {
-                            debug("OVERLAY_TAP_KEY: No tap: Off on release\n");
-                            overlay_off(action.layer.val);
+                            layer_off(action.layer_tap.val);
                         }
                     }
                     break;
             }
             break;
+    #endif
 #endif
         /* Extentions */
 #ifndef NO_ACTION_MACRO
@@ -667,16 +431,9 @@ bool is_tap_key(key_t key)
     switch (action.kind.id) {
         case ACT_LMODS_TAP:
         case ACT_RMODS_TAP:
+        case ACT_LAYER_TAP:
+        case ACT_LAYER_TAP1:
             return true;
-        case ACT_KEYMAP:
-        case ACT_OVERLAY:
-            switch (action.layer.code) {
-                case 0x04 ... 0xEF:    /* tap key */
-                case OP_INV:
-                    return true;
-                default:
-                    return false;
-            }
         case ACT_MACRO:
         case ACT_FUNCTION:
             if (action.func.opt & FUNC_TAP) { return true; }
@@ -714,8 +471,9 @@ void debug_action(action_t action)
         case ACT_RMODS_TAP:         debug("ACT_RMODS_TAP");         break;
         case ACT_USAGE:             debug("ACT_USAGE");             break;
         case ACT_MOUSEKEY:          debug("ACT_MOUSEKEY");          break;
-        case ACT_KEYMAP:            debug("ACT_KEYMAP");            break;
-        case ACT_OVERLAY:           debug("ACT_OVERLAY");           break;
+        case ACT_LAYER:             debug("ACT_LAYER");             break;
+        case ACT_LAYER_TAP:         debug("ACT_LAYER_TAP");         break;
+        case ACT_LAYER_TAP1:        debug("ACT_LAYER_TAP1");        break;
         case ACT_MACRO:             debug("ACT_MACRO");             break;
         case ACT_COMMAND:           debug("ACT_COMMAND");           break;
         case ACT_FUNCTION:          debug("ACT_FUNCTION");          break;
diff --git a/common/action.h b/common/action.h
index a6cb4538..98c4ef81 100644
--- a/common/action.h
+++ b/common/action.h
@@ -21,71 +21,27 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <stdbool.h>
 #include "keyboard.h"
 #include "keycode.h"
+#include "action_code.h"
 #include "action_macro.h"
 
 
+/* tapping count and state */
+typedef struct {
+    bool    interrupted :1;
+    bool    reserved2   :1;
+    bool    reserved1   :1;
+    bool    reserved0   :1;
+    uint8_t count       :4;
+} tap_t;
+
+/* Key event container for recording */
 typedef struct {
     keyevent_t  event;
 #ifndef NO_ACTION_TAPPING
-    /* tapping count and state */
-    struct {
-        bool    interrupted :1;
-        bool    reserved2   :1;
-        bool    reserved1   :1;
-        bool    reserved0   :1;
-        uint8_t count       :4;
-    } tap;
+    tap_t tap;
 #endif
 } keyrecord_t;
 
-/* Action struct.
- *
- * In avr-gcc bit field seems to be assigned from LSB(bit0) to MSB(bit15).
- * AVR looks like a little endian in avr-gcc.
- *
- * NOTE: not portable across compiler/endianness?
- * Byte order and bit order of 0x1234:
- * Big endian:     15 ...  8 7 ... 210
- *                |  0x12   |  0x34   |
- *                 0001 0010 0011 0100
- * Little endian:  012 ... 7  8 ... 15
- *                |  0x34   |  0x12   |
- *                 0010 1100 0100 1000
- */
-typedef union {
-    uint16_t code;
-    struct action_kind {
-        uint16_t param  :12;
-        uint8_t  id     :4;
-    } kind;
-    struct action_key {
-        uint8_t  code   :8;
-        uint8_t  mods   :4;
-        uint8_t  kind   :4;
-    } key;
-    struct action_layer {
-        uint8_t  code   :8;
-        uint8_t  val    :4;
-        uint8_t  kind   :4;
-    } layer;
-    struct action_usage {
-        uint16_t code   :10;
-        uint8_t  page   :2;
-        uint8_t  kind   :4;
-    } usage;
-    struct action_command {
-        uint8_t  id     :8;
-        uint8_t  opt    :4;
-        uint8_t  kind   :4;
-    } command;
-    struct action_function {
-        uint8_t  id     :8;
-        uint8_t  opt    :4;
-        uint8_t  kind   :4;
-    } func;
-} action_t;
-
-
 
 /* Execute action per keyevent */
 void action_exec(keyevent_t event);
@@ -117,255 +73,4 @@ void debug_event(keyevent_t event);
 void debug_record(keyrecord_t record);
 void debug_action(action_t action);
 
-
-
-/*
- * Action codes
- * ============
- * 16bit code: action_kind(4bit) + action_parameter(12bit)
- *
- * Keyboard Keys(00XX)
- * -------------------
- * ACT_LMODS(0000):
- * 0000|0000|000000|00    No action
- * 0000|0000|000000|01    Transparent
- * 0000|0000| keycode     Key
- * 0000|mods|000000|00    Left mods
- * 0000|mods| keycode     Key & Left mods
- *
- * ACT_RMODS(0001):
- * 0001|0000|000000|00    No action(not used)
- * 0001|0000|000000|01    Transparent(not used)
- * 0001|0000| keycode     Key(no used)
- * 0001|mods|000000|00    Right mods
- * 0001|mods| keycode     Key & Right mods
- *
- * ACT_LMODS_TAP(0010):
- * 0010|mods|000000|00    Left mods OneShot
- * 0010|mods|000000|01    (reserved)
- * 0010|mods|000000|10    (reserved)
- * 0010|mods|000000|11    (reserved)
- * 0010|mods| keycode     Left mods + tap Key
- *
- * ACT_RMODS_TAP(0011):
- * 0011|mods|000000|00    Right mods OneShot
- * 0011|mods|000000|01    (reserved)
- * 0011|mods|000000|10    (reserved)
- * 0011|mods|000000|11    (reserved)
- * 0011|mods| keycode     Right mods + tap Key
- *
- *
- * Other keys(01XX)
- * --------------------
- * This action handles other usages than keyboard.
- * ACT_USAGE(0100):
- * 0100|00| usage(10)     System control(0x80) - General Desktop page(0x01)
- * 0100|01| usage(10)     Consumer control(0x01) - Consumer page(0x0C)
- * 0100|10| usage(10)     (reserved)
- * 0100|11| usage(10)     (reserved)
- *
- * ACT_MOUSEKEY(0110):
- * 0101|XXXX| keycode     Mouse key
- *
- *
- * Layer Actions(10XX)
- * -------------------
- * ACT_KEYMAP:
- * 1000|--xx|0000 0000   Clear keyamp and overlay
- * 1000|LLLL|0000 00xx   Reset default layer and clear keymap and overlay
- * 1000|LLLL| keycode    Invert with tap key
- * 1000|LLLL|1111 0000   Invert with tap toggle
- * 1000|LLLL|1111 00xx   Invert[^=  1<<L]
- * 1000|LLLL|1111 0100   On/Off
- * 1000|LLLL|1111 01xx   On[|= 1<<L]
- * 1000|LLLL|1111 1000   Off/On
- * 1000|LLLL|1111 10xx   Off[&= ~(1<<L)]
- * 1000|LLLL|1111 1100   Set/Clear
- * 1000|LLLL|1111 11xx   Set[= 1<<L]
- * default layer: 0-15(4bit)
- * xx: On {00:for special use, 01:press, 10:release, 11:both}
- *
- * ACT_OVERLAY:
- * 1011|0000|0000 0000   Clear overlay
- * 1011|LLLL|0000 00ss   Invert 4-bit chunk [^= L<<(4*ss)]
- * 1011|LLLL| keycode    Invert with tap key
- * 1011|LLLL|1111 0000   Invert with tap toggle
- * 1011|LLLL|1111 00xx   Invert[^= 1<<L]
- * 1011|LLLL|1111 0100   On/Off(momentary)
- * 1011|LLLL|1111 01xx   On[|= 1<<L]
- * 1011|LLLL|1111 1000   Off/On
- * 1011|LLLL|1111 10xx   Off[&= ~(1<<L)]
- * 1011|LLLL|1111 1100   Set/Clear
- * 1011|LLLL|1111 11xx   Set[= 1<<L]
- * overlays: 16-layer on/off status(16bit)
- * xx: On {00:for special use, 01:press, 10:release, 11:both}
- *
- *
- * Extensions(11XX)
- * ----------------
- * ACT_MACRO(1100):
- * 1100|opt | id(8)      Macro play?
- * 1100|1111| id(8)      Macro record?
- *
- * ACT_COMMAND(1110):
- * 1110|opt | id(8)      Built-in Command exec
- *
- * ACT_FUNCTION(1111):
- * 1111| address(12)     Function?
- * 1111|opt | id(8)      Function?
- *
- */
-enum action_kind_id {
-    ACT_LMODS           = 0b0000,
-    ACT_RMODS           = 0b0001,
-    ACT_LMODS_TAP       = 0b0010,
-    ACT_RMODS_TAP       = 0b0011,
-
-    ACT_USAGE           = 0b0100,
-    ACT_MOUSEKEY        = 0b0101,
-
-    ACT_KEYMAP          = 0b1000,
-    ACT_OVERLAY         = 0b1001,
-
-    ACT_MACRO           = 0b1100,
-    ACT_COMMAND         = 0b1110,
-    ACT_FUNCTION        = 0b1111
-};
-
-
-/* action utility */
-#define ACTION_NO                       0
-#define ACTION_TRANSPARENT              1
-#define ACTION(kind, param)             ((kind)<<12 | (param))
-#define MODS4(mods)                     (((mods)>>4 | (mods)) & 0x0F)
-
-/*
- * Key
- */
-#define ACTION_KEY(key)                 ACTION(ACT_LMODS,    key)
-/* Mods & key */
-#define ACTION_LMODS(mods)              ACTION(ACT_LMODS,    MODS4(mods)<<8 | 0x00)
-#define ACTION_LMODS_KEY(mods, key)     ACTION(ACT_LMODS,    MODS4(mods)<<8 | (key))
-#define ACTION_RMODS(mods)              ACTION(ACT_RMODS,    MODS4(mods)<<8 | 0x00)
-#define ACTION_RMODS_KEY(mods, key)     ACTION(ACT_RMODS,    MODS4(mods)<<8 | (key))
-#define ACTION_LMOD(mod)                ACTION(ACT_LMODS,    MODS4(MOD_BIT(mod))<<8 | 0x00)
-#define ACTION_LMOD_KEY(mod, key)       ACTION(ACT_LMODS,    MODS4(MOD_BIT(mod))<<8 | (key))
-#define ACTION_RMOD(mod)                ACTION(ACT_RMODS,    MODS4(MOD_BIT(mod))<<8 | 0x00)
-#define ACTION_RMOD_KEY(mod, key)       ACTION(ACT_RMODS,    MODS4(MOD_BIT(mod))<<8 | (key))
-/* Tap key */
-enum mods_codes {
-    MODS_ONESHOT           = 0x00,
-};
-#define ACTION_LMODS_TAP_KEY(mods, key) ACTION(ACT_LMODS_TAP, MODS4(mods)<<8 | (key))
-#define ACTION_LMODS_ONESHOT(mods)      ACTION(ACT_LMODS_TAP, MODS4(mods)<<8 | MODS_ONESHOT)
-#define ACTION_RMODS_TAP_KEY(mods, key) ACTION(ACT_RMODS_TAP, MODS4(mods)<<8 | (key))
-#define ACTION_RMODS_ONESHOT(mods)      ACTION(ACT_RMODS_TAP, MODS4(mods)<<8 | MODS_ONESHOT)
-#define ACTION_LMOD_TAP_KEY(mod, key)   ACTION(ACT_LMODS_TAP, MODS4(MOD_BIT(mod))<<8 | (key))
-#define ACTION_LMOD_ONESHOT(mod)        ACTION(ACT_LMODS_TAP, MODS4(MOD_BIT(mod))<<8 | MODS_ONESHOT)
-#define ACTION_RMOD_TAP_KEY(mod, key)   ACTION(ACT_RMODS_TAP, MODS4(MOD_BIT(mod))<<8 | (key))
-#define ACTION_RMOD_ONESHOT(mod)        ACTION(ACT_RMODS_TAP, MODS4(MOD_BIT(mod))<<8 | MODS_ONESHOT)
-
-/* HID Usage */
-enum usage_pages {
-    PAGE_SYSTEM,
-    PAGE_CONSUMER
-};
-#define ACTION_USAGE_SYSTEM(id)         ACTION(ACT_USAGE, PAGE_SYSTEM<<10 | (id))
-#define ACTION_USAGE_CONSUMER(id)       ACTION(ACT_USAGE, PAGE_CONSUMER<<10 | (id))
-
-/* Mousekey */
-#define ACTION_MOUSEKEY(key)            ACTION(ACT_MOUSEKEY, key)
-
-
-
-/* Layer Actions:
- *      Invert  layer ^= (1<<layer)
- *      On      layer |= (1<<layer)
- *      Off     layer &= ~(1<<layer)
- *      Set     layer = (1<<layer)
- *      Clear   layer = 0
- */
-enum layer_params {
-    ON_PRESS    = 1,
-    ON_RELEASE  = 2,
-    ON_BOTH     = 3,
-
-    OP_RESET  = 0x00,
-    OP_INV4  = 0x00,
-    OP_INV   = 0xF0,
-    OP_ON    = 0xF4,
-    OP_OFF   = 0xF8,
-    OP_SET   = 0xFC,
-};
-
-/* 
- * Default Layer
- */
-#define ACTION_DEFAULT_LAYER                     ACTION(ACT_KEYMAP, ON_RELEASE<<8 | OP_RESET | 0)
-#define ACTION_DEFAULT_LAYER_SET(layer)          ACTION_DEFAULT_LAYER_TO(layer, ON_RELEASE)
-#define ACTION_DEFAULT_LAYER_TO(layer, on)       ACTION(ACT_KEYMAP, (layer)<<8 | OP_RESET | (on))
-/*
- * Keymap Layer
- */
-#define ACTION_KEYMAP_MOMENTARY(layer)           ACTION_KEYMAP_ON_OFF(layer)
-#define ACTION_KEYMAP_TOGGLE(layer)              ACTION_KEYMAP_INV(layer, ON_RELEASE)
-/* Keymap Invert */
-#define ACTION_KEYMAP_INV(layer, on)             ACTION(ACT_KEYMAP, (layer)<<8 | OP_INV | (on))
-#define ACTION_KEYMAP_TAP_TOGGLE(layer)          ACTION(ACT_KEYMAP, (layer)<<8 | OP_INV | 0)
-/* Keymap On */
-#define ACTION_KEYMAP_ON(layer, on)              ACTION(ACT_KEYMAP, (layer)<<8 | OP_ON  | (on))
-#define ACTION_KEYMAP_ON_OFF(layer)              ACTION(ACT_KEYMAP, (layer)<<8 | OP_ON  | 0)
-/* Keymap Off */
-#define ACTION_KEYMAP_OFF(layer, on)             ACTION(ACT_KEYMAP, (layer)<<8 | OP_OFF | (on))
-#define ACTION_KEYMAP_OFF_ON(layer)              ACTION(ACT_KEYMAP, (layer)<<8 | OP_OFF | 0)
-/* Keymap Set */
-#define ACTION_KEYMAP_SET(layer, on)             ACTION(ACT_KEYMAP, (layer)<<8 | OP_SET | (on))
-#define ACTION_KEYMAP_SET_CLEAR(layer)           ACTION(ACT_KEYMAP, (layer)<<8 | OP_SET | 0)
-/* Keymap Invert with tap key */
-#define ACTION_KEYMAP_TAP_KEY(layer, key)        ACTION(ACT_KEYMAP, (layer)<<8 | (key))
-
-/*
- * Overlay Layer
- */
-#define ACTION_OVERLAY_MOMENTARY(layer)           ACTION_OVERLAY_ON_OFF(layer)
-#define ACTION_OVERLAY_TOGGLE(layer)              ACTION_OVERLAY_INV(layer, ON_RELEASE)
-/* Overlay Clear */
-#define ACTION_OVERLAY_CLEAR(on)                  ACTION(ACT_OVERLAY, 0<<8 | OP_INV4 | (on))
-/* Overlay Invert 4-bit chunk */
-#define ACTION_OVERLAY_INV4(bits, shift)          ACTION(ACT_OVERLAY, (bits)<<8 | OP_INV4 | shift)
-/* Overlay Invert */
-#define ACTION_OVERLAY_INV(layer, on)             ACTION(ACT_OVERLAY, (layer)<<8 | OP_INV | (on))
-#define ACTION_OVERLAY_TAP_TOGGLE(layer)          ACTION(ACT_OVERLAY, (layer)<<8 | OP_INV | 0)
-/* Overlay On */
-#define ACTION_OVERLAY_ON(layer, on)              ACTION(ACT_OVERLAY, (layer)<<8 | OP_ON  | (on))
-#define ACTION_OVERLAY_ON_OFF(layer)              ACTION(ACT_OVERLAY, (layer)<<8 | OP_ON  | 0)
-/* Overlay Off */
-#define ACTION_OVERLAY_OFF(layer, on)             ACTION(ACT_OVERLAY, (layer)<<8 | OP_OFF | (on))
-#define ACTION_OVERLAY_OFF_ON(layer)              ACTION(ACT_OVERLAY, (layer)<<8 | OP_OFF | 0)
-/* Overlay Set */
-#define ACTION_OVERLAY_SET(layer, on)             ACTION(ACT_OVERLAY, (layer)<<8 | OP_SET | (on))
-#define ACTION_OVERLAY_SET_CLEAR(layer)           ACTION(ACT_OVERLAY, (layer)<<8 | OP_SET | 0)
-/* Overlay Invert with tap key */
-#define ACTION_OVERLAY_TAP_KEY(layer, key)        ACTION(ACT_OVERLAY, (layer)<<8 | (key))
-
-
-/*
- * Extensions
- */
-/* Macro */
-#define ACTION_MACRO(id)                ACTION(ACT_MACRO, (id))
-#define ACTION_MACRO_TAP(id)            ACTION(ACT_MACRO, FUNC_TAP<<8 | (id))
-#define ACTION_MACRO_OPT(id, opt)       ACTION(ACT_MACRO, (opt)<<8 | (id))
-
-/* Command */
-#define ACTION_COMMAND(id, opt)         ACTION(ACT_COMMAND,  (opt)<<8 | (addr))
-
-/* Function */
-enum function_opts {
-    FUNC_TAP        = 0x8,      /* indciates function is tappable */
-};
-#define ACTION_FUNCTION(id)             ACTION(ACT_FUNCTION, (id))
-#define ACTION_FUNCTION_TAP(id)         ACTION(ACT_FUNCTION, FUNC_TAP<<8 | (id))
-#define ACTION_FUNCTION_OPT(id, opt)    ACTION(ACT_FUNCTION, (opt)<<8 | (id))
-
 #endif  /* ACTION_H */
diff --git a/common/action_code.h b/common/action_code.h
new file mode 100644
index 00000000..0933dce1
--- /dev/null
+++ b/common/action_code.h
@@ -0,0 +1,289 @@
+/*
+Copyright 2013 Jun Wako <wakojun@gmail.com>
+
+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/>.
+*/
+#ifndef ACTION_CODE_H
+#define ACTION_CODE_H
+
+/* Action codes
+ * ============
+ * 16bit code: action_kind(4bit) + action_parameter(12bit)
+ *
+ *
+ * Key Actions(00xx)
+ * -----------------
+ * ACT_MODS(000r):
+ * 000r|0000|0000 0000    No action code
+ * 000r|0000|0000 0001    Transparent code
+ * 000r|0000| keycode     Key
+ * 000r|mods|0000 0000    Modifiers
+ * 000r|mods| keycode     Key and Modifiers
+ *   r: Left/Right flag(Left:0, Right:1)
+ *
+ * ACT_MODS_TAP(001r):
+ * 0010|mods|0000 0000    Modifiers with OneShot
+ * 0010|mods|0000 00xx    (reserved)
+ * 0010|mods| keycode     Modifiers with Tap Key
+ *
+ *
+ * Other Keys(01xx)
+ * ----------------
+ * ACT_USAGE(0100): TODO: Not needed?
+ * 0100|00| usage(10)     System control(0x80) - General Desktop page(0x01)
+ * 0100|01| usage(10)     Consumer control(0x01) - Consumer page(0x0C)
+ * 0100|10| usage(10)     (reserved)
+ * 0100|11| usage(10)     (reserved)
+ *
+ * ACT_MOUSEKEY(0110): TODO: Not needed?
+ * 0101|xxxx| keycode     Mouse key
+ *
+ * 011x|xxxx xxxx xxxx    (reseved)
+ *
+ *
+ * Layer Actions(10xx)
+ * -------------------
+ * ACT_LAYER(1000):
+ * 1000|oo00|pppE BBBB   Default Layer Bitwise operation
+ *   oo:    operation(00:AND, 01:OR, 10:XOR, 11:SET)
+ *   ppp:   4-bit chunk part(0-7)
+ *   EBBBB: bits and extra bit
+ * 1000|ooee|pppE BBBB   Layer Bitwise Operation
+ *   oo:    operation(00:AND, 01:OR, 10:XOR, 11:SET)
+ *   ppp:   4-bit chunk part(0-7)
+ *   eBBBB: bits and extra bit
+ *   ee:    on event(00:default layer, 01:press, 10:release, 11:both)
+ *
+ * 1001|xxxx|xxxx xxxx   (reserved)
+ * 1001|oopp|BBBB BBBB   8-bit Bitwise Operation???
+ *
+ * ACT_LAYER_TAP(101x):
+ * 101E|LLLL| keycode    Invert with tap key
+ * 101E|LLLL|1110 xxxx   Reserved(0xE0-EF)
+ * 101E|LLLL|1111 0000   Invert with tap toggle(0xF0)
+ * 101E|LLLL|1111 0001   On/Off
+ * 101E|LLLL|1111 0010   Off/On
+ * 101E|LLLL|1111 0011   Set/Clear
+ * 101E|LLLL|1111 xxxx   Reserved(0xF4-FF)
+ *   ELLLL: layer(0-31)
+ *
+ *
+ * Extensions(11xx)
+ * ----------------
+ * ACT_MACRO(1100):
+ * 1100|opt | id(8)      Macro play?
+ * 1100|1111| id(8)      Macro record?
+ *
+ * ACT_COMMAND(1110):
+ * 1110|opt | id(8)      Built-in Command exec
+ *
+ * ACT_FUNCTION(1111):
+ * 1111| address(12)     Function?
+ * 1111|opt | id(8)      Function?
+ */
+enum action_kind_id {
+    /* Key Actions */
+    ACT_MODS            = 0b0000,
+    ACT_LMODS           = 0b0000,
+    ACT_RMODS           = 0b0001,
+    ACT_MODS_TAP        = 0b0010,
+    ACT_LMODS_TAP       = 0b0010,
+    ACT_RMODS_TAP       = 0b0011,
+    /* Other Keys */
+    ACT_USAGE           = 0b0100,
+    ACT_MOUSEKEY        = 0b0101,
+    /* Layer Actions */
+    ACT_LAYER           = 0b1000,
+    ACT_LAYER_TAP       = 0b1010,
+    ACT_LAYER_TAP1      = 0b1011,
+    /* Extensions */
+    ACT_MACRO           = 0b1100,
+    ACT_COMMAND         = 0b1110,
+    ACT_FUNCTION        = 0b1111
+};
+
+
+/* Action Code Struct
+ *
+ * NOTE:
+ * In avr-gcc bit field seems to be assigned from LSB(bit0) to MSB(bit15).
+ * AVR looks like a little endian in avr-gcc.
+ * Not portable across compiler/endianness?
+ *
+ * Byte order and bit order of 0x1234:
+ *   Big endian:                Little endian:
+ *   --------------------       --------------------
+ *   FEDC BA98  7654 3210       0123 4567  89AB CDEF
+ *   0001 0010  0011 0100       0010 1100  0100 1000
+ *     0x12       0x34            0x34       0x12
+ */
+typedef union {
+    uint16_t code;
+    struct action_kind {
+        uint16_t param  :12;
+        uint8_t  id     :4;
+    } kind;
+    struct action_key {
+        uint8_t  code   :8;
+        uint8_t  mods   :4;
+        uint8_t  kind   :4;
+    } key;
+    struct action_layer_bitop {
+        uint8_t  bits   :4;
+        uint8_t  xbit   :1;
+        uint8_t  part   :3;
+        uint8_t  on     :2;
+        uint8_t  op     :2;
+        uint8_t  kind   :4;
+    } layer_bitop;
+    struct action_layer_tap {
+        uint8_t  code   :8;
+        uint8_t  val    :5;
+        uint8_t  kind   :3;
+    } layer_tap;
+    struct action_usage {
+        uint16_t code   :10;
+        uint8_t  page   :2;
+        uint8_t  kind   :4;
+    } usage;
+    struct action_command {
+        uint8_t  id     :8;
+        uint8_t  opt    :4;
+        uint8_t  kind   :4;
+    } command;
+    struct action_function {
+        uint8_t  id     :8;
+        uint8_t  opt    :4;
+        uint8_t  kind   :4;
+    } func;
+} action_t;
+
+
+/* action utility */
+#define ACTION_NO                       0
+#define ACTION_TRANSPARENT              1
+#define ACTION(kind, param)             ((kind)<<12 | (param))
+
+
+/*
+ * Key Actions
+ */
+/* Mod bits:    43210
+ *   bit 0      ||||+- Control
+ *   bit 1      |||+-- Shift
+ *   bit 2      ||+--- Alt
+ *   bit 3      |+---- Gui
+ *   bit 4      +----- LR flag(Left:0, Right:1)
+ */
+enum mods_bit {
+    MOD_LCTL = 0x01,
+    MOD_LSFT = 0x02,
+    MOD_LALT = 0x04,
+    MOD_LGUI = 0x08,
+    MOD_RCTL = 0x11,
+    MOD_RSFT = 0x12,
+    MOD_RALT = 0x14,
+    MOD_RGUI = 0x18,
+};
+enum mods_codes {
+    MODS_ONESHOT = 0x00,
+};
+#define ACTION_KEY(key)                 ACTION(ACT_MODS, (key))
+#define ACTION_MODS(mods)               ACTION(ACT_MODS, (mods)<<8 | 0)
+#define ACTION_MODS_KEY(mods, key)      ACTION(ACT_MODS, (mods)<<8 | (key))
+#define ACTION_MODS_TAP_KEY(mods, key)  ACTION(ACT_MODS_TAP, (mods)<<8 | (key))
+#define ACTION_MODS_ONESHOT(mods)       ACTION(ACT_MODS_TAP, (mods)<<8 | MODS_ONESHOT)
+
+
+/*
+ * Other Keys
+ */
+enum usage_pages {
+    PAGE_SYSTEM,
+    PAGE_CONSUMER
+};
+#define ACTION_USAGE_SYSTEM(id)         ACTION(ACT_USAGE, PAGE_SYSTEM<<10 | (id))
+#define ACTION_USAGE_CONSUMER(id)       ACTION(ACT_USAGE, PAGE_CONSUMER<<10 | (id))
+#define ACTION_MOUSEKEY(key)            ACTION(ACT_MOUSEKEY, key)
+
+
+
+/* 
+ * Layer Actions
+ */
+enum layer_param_on {
+    ON_PRESS    = 1,
+    ON_RELEASE  = 2,
+    ON_BOTH     = 3,
+};
+enum layer_param_bit_op {
+    OP_BIT_AND = 0,
+    OP_BIT_OR  = 1,
+    OP_BIT_XOR = 2,
+    OP_BIT_SET = 3,
+};
+enum layer_pram_tap_op {
+    OP_TAP_TOGGLE = 0xF0,
+    OP_ON_OFF,
+    OP_OFF_ON,
+    OP_SET_CLEAR,
+};
+#define ACTION_LAYER_BITOP(op, part, bits, on)      (ACT_LAYER<<12 | (op)<<10 | (on)<<8 | (part)<<5 | ((bits)&0x1f))
+#define ACTION_LAYER_TAP(layer, key)                (ACT_LAYER_TAP<<12 | (layer)<<8 | (key))
+/* Default Layer */
+#define ACTION_DEFAULT_LAYER_SET(layer)             ACTION_DEFAULT_LAYER_BIT_SET((layer)/4, 1<<((layer)%4))
+/* Layer Operation */
+#define ACTION_LAYER_CLEAR(on)                      ACTION_LAYER_BIT_AND(0, 0, (on))
+#define ACTION_LAYER_MOMENTARY(layer)               ACTION_LAYER_ON_OFF(layer)
+#define ACTION_LAYER_TOGGLE(layer)                  ACTION_LAYER_INVERT(layer, ON_RELEASE)
+#define ACTION_LAYER_INVERT(layer, on)              ACTION_LAYER_BIT_XOR((layer)/4,   1<<((layer)%4),  (on))
+#define ACTION_LAYER_ON(layer, on)                  ACTION_LAYER_BIT_OR( (layer)/4,   1<<((layer)%4),  (on))
+#define ACTION_LAYER_OFF(layer, on)                 ACTION_LAYER_BIT_AND((layer)/4, ~(1<<((layer)%4)), (on))
+#define ACTION_LAYER_SET(layer, on)                 ACTION_LAYER_BIT_SET((layer)/4,   1<<((layer)%4),  (on))
+#define ACTION_LAYER_ON_OFF(layer)                  ACTION_LAYER_TAP((layer), OP_ON_OFF)
+#define ACTION_LAYER_OFF_ON(layer)                  ACTION_LAYER_TAP((layer), OP_OFF_ON)
+#define ACTION_LAYER_SET_CLEAR(layer)               ACTION_LAYER_TAP((layer), OP_SET_CLEAR)
+/* With Tapping */
+#define ACTION_LAYER_TAP_KEY(layer, key)            ACTION_LAYER_TAP((layer), (key))
+#define ACTION_LAYER_TAP_TOGGLE(layer)              ACTION_LAYER_TAP((layer), OP_TAP_TOGGLE)
+/* Bitwise Operation */
+#define ACTION_LAYER_BIT_AND(part, bits, on)        ACTION_LAYER_BITOP(OP_BIT_AND, (part), (bits), (on))
+#define ACTION_LAYER_BIT_OR( part, bits, on)        ACTION_LAYER_BITOP(OP_BIT_OR,  (part), (bits), (on))
+#define ACTION_LAYER_BIT_XOR(part, bits, on)        ACTION_LAYER_BITOP(OP_BIT_XOR, (part), (bits), (on))
+#define ACTION_LAYER_BIT_SET(part, bits, on)        ACTION_LAYER_BITOP(OP_BIT_SET, (part), (bits), (on))
+/* Default Layer Bitwise Operation */
+#define ACTION_DEFAULT_LAYER_BIT_AND(part, bits)    ACTION_LAYER_BITOP(OP_BIT_AND, (part), (bits), 0)
+#define ACTION_DEFAULT_LAYER_BIT_OR( part, bits)    ACTION_LAYER_BITOP(OP_BIT_OR,  (part), (bits), 0)
+#define ACTION_DEFAULT_LAYER_BIT_XOR(part, bits)    ACTION_LAYER_BITOP(OP_BIT_XOR, (part), (bits), 0)
+#define ACTION_DEFAULT_LAYER_BIT_SET(part, bits)    ACTION_LAYER_BITOP(OP_BIT_SET, (part), (bits), 0)
+
+
+/*
+ * Extensions
+ */
+/* Macro */
+#define ACTION_MACRO(id)                ACTION(ACT_MACRO, (id))
+#define ACTION_MACRO_TAP(id)            ACTION(ACT_MACRO, FUNC_TAP<<8 | (id))
+#define ACTION_MACRO_OPT(id, opt)       ACTION(ACT_MACRO, (opt)<<8 | (id))
+/* Command */
+#define ACTION_COMMAND(id, opt)         ACTION(ACT_COMMAND,  (opt)<<8 | (addr))
+/* Function */
+enum function_opts {
+    FUNC_TAP = 0x8,     /* indciates function is tappable */
+};
+#define ACTION_FUNCTION(id)             ACTION(ACT_FUNCTION, (id))
+#define ACTION_FUNCTION_TAP(id)         ACTION(ACT_FUNCTION, FUNC_TAP<<8 | (id))
+#define ACTION_FUNCTION_OPT(id, opt)    ACTION(ACT_FUNCTION, (opt)<<8 | (id))
+
+#endif /* ACTION_CODE_H */
diff --git a/common/action_layer.c b/common/action_layer.c
new file mode 100644
index 00000000..3413c53e
--- /dev/null
+++ b/common/action_layer.c
@@ -0,0 +1,135 @@
+#include <stdint.h>
+#include "keyboard.h"
+#include "action.h"
+#include "debug.h"
+#include "util.h"
+#include "action_layer.h"
+
+
+/* 
+ * Default Layer State
+ */
+uint32_t default_layer_state = 0;
+
+static void default_layer_state_set(uint32_t state)
+{
+    debug("default_layer_state: ");
+    default_layer_debug(); debug(" to ");
+    default_layer_state = state;
+    default_layer_debug(); debug("\n");
+    clear_keyboard_but_mods(); // To avoid stuck keys
+}
+
+void default_layer_debug(void)
+{
+    debug_hex32(default_layer_state);
+    debug("("); debug_dec(biton32(default_layer_state)); debug(")");
+}
+
+void default_layer_set(uint8_t layer)
+{
+    default_layer_state_set(1UL<<layer);
+}
+
+#ifndef NO_ACTION_LAYER
+void default_layer_or(uint32_t state)
+{
+    default_layer_state_set(default_layer_state | state);
+}
+void default_layer_and(uint32_t state)
+{
+    default_layer_state_set(default_layer_state & state);
+}
+void default_layer_xor(uint32_t state)
+{
+    default_layer_state_set(default_layer_state ^ state);
+}
+#endif
+
+
+#ifndef NO_ACTION_LAYER
+/* 
+ * Keymap Layer State
+ */
+uint32_t layer_state = 0;
+
+static void layer_state_set(uint32_t state)
+{
+    debug("layer_state: ");
+    layer_debug(); debug(" to ");
+    layer_state = state;
+    layer_debug(); debug("\n");
+    clear_keyboard_but_mods(); // To avoid stuck keys
+}
+
+void layer_clear(void)
+{
+    layer_state_set(0);
+}
+
+void layer_move(uint8_t layer)
+{
+    layer_state_set(1UL<<layer);
+}
+
+void layer_on(uint8_t layer)
+{
+    layer_state_set(layer_state | (1UL<<layer));
+}
+
+void layer_off(uint8_t layer)
+{
+    layer_state_set(layer_state & ~(1UL<<layer));
+}
+
+void layer_invert(uint8_t layer)
+{
+    layer_state_set(layer_state ^ (1UL<<layer));
+}
+
+void layer_or(uint32_t state)
+{
+    layer_state_set(layer_state | state);
+}
+void layer_and(uint32_t state)
+{
+    layer_state_set(layer_state & state);
+}
+void layer_xor(uint32_t state)
+{
+    layer_state_set(layer_state ^ state);
+}
+
+void layer_debug(void)
+{
+    debug_hex32(layer_state);
+    debug("("); debug_dec(biton32(layer_state)); debug(")");
+}
+#endif
+
+
+
+action_t layer_switch_get_action(key_t key)
+{
+    action_t action;
+    action.code = ACTION_TRANSPARENT;
+
+#ifndef NO_ACTION_LAYER
+    uint32_t layers = layer_state | default_layer_state;
+    /* check top layer first */
+    for (int8_t i = 31; i >= 0; i--) {
+        if (layers & (1UL<<i)) {
+            action = action_for_key(i, key);
+            if (action.code != ACTION_TRANSPARENT) {
+                return action;
+            }
+        }
+    }
+    /* fall back to layer 0 */
+    action = action_for_key(0, key);
+    return action;
+#else
+    action = action_for_key(biton32(default_layer_state), key);
+    return action;
+#endif
+}
diff --git a/common/action_layer.h b/common/action_layer.h
new file mode 100644
index 00000000..23f8a00b
--- /dev/null
+++ b/common/action_layer.h
@@ -0,0 +1,77 @@
+/*
+Copyright 2013 Jun Wako <wakojun@gmail.com>
+
+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/>.
+*/
+#ifndef ACTION_LAYER_H
+#define ACTION_LAYER_H
+
+#include <stdint.h>
+#include "keyboard.h"
+#include "action.h"
+
+
+/*
+ * Default Layer
+ */
+extern uint32_t default_layer_state;
+void default_layer_debug(void);
+void default_layer_set(uint8_t layer);
+
+#ifndef NO_ACTION_LAYER
+/* bitwise operation */
+void default_layer_or(uint32_t state);
+void default_layer_and(uint32_t state);
+void default_layer_xor(uint32_t state);
+#else
+#define default_layer_or(state)
+#define default_layer_and(state)
+#define default_layer_xor(state)
+#endif
+
+
+/*
+ * Keymap Layer
+ */
+#ifndef NO_ACTION_LAYER
+extern uint32_t layer_state;
+void layer_debug(void);
+void layer_clear(void);
+void layer_move(uint8_t layer);
+void layer_on(uint8_t layer);
+void layer_off(uint8_t layer);
+void layer_invert(uint8_t layer);
+/* bitwise operation */
+void layer_or(uint32_t state);
+void layer_and(uint32_t state);
+void layer_xor(uint32_t state);
+#else
+#define layer_state             0
+#define layer_clear()
+#define layer_move(layer)
+#define layer_on(layer)
+#define layer_off(layer)
+#define layer_invert(layer)
+
+#define layer_or(state)
+#define layer_and(state)
+#define layer_xor(state)
+#define layer_debug()
+#endif
+
+
+/* return action depending on current layer status */
+action_t layer_switch_get_action(key_t key);
+
+#endif
diff --git a/common/action_tapping.h b/common/action_tapping.h
index c9f09f57..9b42d50d 100644
--- a/common/action_tapping.h
+++ b/common/action_tapping.h
@@ -18,7 +18,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define ACTION_TAPPING_H
 
 
-#ifndef NO_ACTION_TAPPING
 
 /* period of tapping(ms) */
 #ifndef TAPPING_TERM
@@ -33,8 +32,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define WAITING_BUFFER_SIZE 8
 
 
+#ifndef NO_ACTION_TAPPING
 void action_tapping_process(keyrecord_t record);
-
 #endif
 
 #endif
diff --git a/common/command.c b/common/command.c
index b2933388..3a1fcb18 100644
--- a/common/command.c
+++ b/common/command.c
@@ -26,7 +26,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "timer.h"
 #include "keyboard.h"
 #include "bootloader.h"
-#include "layer_switch.h"
+#include "action_layer.h"
 #include "eeconfig.h"
 #include "sleep_led.h"
 #include "led.h"
@@ -573,8 +573,8 @@ static uint8_t numkey2num(uint8_t code)
 
 static void switch_default_layer(uint8_t layer)
 {
-    print("switch_default_layer: "); print_dec(default_layer); print(" to "); print_dec(layer); print("\n");
+    print("switch_default_layer: "); print_dec(biton32(default_layer_state));
+    print(" to "); print_dec(layer); print("\n");
     default_layer_set(layer);
-    overlay_clear();
     clear_keyboard();
 }
diff --git a/common/keymap.c b/common/keymap.c
index ace3f49b..c98ce09b 100644
--- a/common/keymap.c
+++ b/common/keymap.c
@@ -18,7 +18,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "keymap.h"
 #include "report.h"
 #include "keycode.h"
-#include "layer_switch.h"
+#include "action_layer.h"
 #include "action.h"
 #include "action_macro.h"
 #include "debug.h"
diff --git a/common/layer_switch.c b/common/layer_switch.c
deleted file mode 100644
index a5d426a8..00000000
--- a/common/layer_switch.c
+++ /dev/null
@@ -1,209 +0,0 @@
-#include <stdint.h>
-#include "keyboard.h"
-#include "action.h"
-#include "debug.h"
-#include "util.h"
-#include "layer_switch.h"
-
-
-/* 
- * Default Layer (0-15)
- */
-uint8_t default_layer = 0;
-
-void default_layer_set(uint8_t layer)
-{
-    debug("default_layer_set: ");
-    debug_dec(default_layer); debug(" to ");
-
-    default_layer = layer;
-
-    debug_dec(default_layer); debug("\n");
-
-    clear_keyboard_but_mods(); // To avoid stuck keys
-}
-
-
-#ifndef NO_ACTION_KEYMAP
-/* 
- * Keymap Layer (0-15)
- */
-uint16_t keymap_stat = 0;
-
-/* return highest layer whose state is on */
-uint8_t keymap_get_layer(void)
-{
-    return biton16(keymap_stat);
-}
-
-static void keymap_stat_set(uint16_t stat)
-{
-    debug("keymap: ");
-    keymap_debug(); debug(" to ");
-
-    keymap_stat = stat;
-
-    keymap_debug(); debug("\n");
-
-    clear_keyboard_but_mods(); // To avoid stuck keys
-}
-
-void keymap_clear(void)
-{
-    keymap_stat_set(0);
-}
-
-
-void keymap_set(uint16_t stat)
-{
-    keymap_stat_set(stat);
-}
-
-void keymap_move(uint8_t layer)
-{
-    keymap_stat_set(1<<layer);
-}
-
-void keymap_on(uint8_t layer)
-{
-    keymap_stat_set(keymap_stat | (1<<layer));
-}
-
-void keymap_off(uint8_t layer)
-{
-    keymap_stat_set(keymap_stat & ~(1<<layer));
-}
-
-void keymap_invert(uint8_t layer)
-{
-    keymap_stat_set(keymap_stat ^ (1<<layer));
-}
-
-void keymap_or(uint16_t stat)
-{
-    keymap_stat_set(keymap_stat | stat);
-}
-void keymap_and(uint16_t stat)
-{
-    keymap_stat_set(keymap_stat & stat);
-}
-void keymap_xor(uint16_t stat)
-{
-    keymap_stat_set(keymap_stat ^ stat);
-}
-
-void keymap_debug(void)
-{
-    debug_hex16(keymap_stat); debug("("); debug_dec(keymap_get_layer()); debug(")");
-}
-#endif
-
-
-
-#ifndef NO_ACTION_OVERLAY
-/* 
- * Overlay Layer (16-31 = 0-15|0x10)
- */
-uint16_t overlay_stat = 0;
-
-/* return highest layer whose state is on */
-uint8_t overlay_get_layer(void)
-{
-    return biton16(overlay_stat);
-}
-
-static void overlay_stat_set(uint16_t stat)
-{
-    debug("overlay: ");
-    overlay_debug(); debug(" to ");
-
-    overlay_stat = stat;
-
-    overlay_debug(); debug("\n");
-
-    clear_keyboard_but_mods(); // To avoid stuck keys
-}
-
-void overlay_clear(void)
-{
-    overlay_stat_set(0);
-}
-
-
-void overlay_set(uint16_t stat)
-{
-    overlay_stat_set(stat);
-}
-
-void overlay_move(uint8_t layer)
-{
-    overlay_stat_set(1<<layer);
-}
-
-void overlay_on(uint8_t layer)
-{
-    overlay_stat_set(overlay_stat | (1<<layer));
-}
-
-void overlay_off(uint8_t layer)
-{
-    overlay_stat_set(overlay_stat & ~(1<<layer));
-}
-
-void overlay_invert(uint8_t layer)
-{
-    overlay_stat_set(overlay_stat ^ (1<<layer));
-}
-
-void overlay_or(uint16_t stat)
-{
-    overlay_stat_set(overlay_stat | stat);
-}
-void overlay_and(uint16_t stat)
-{
-    overlay_stat_set(overlay_stat & stat);
-}
-void overlay_xor(uint16_t stat)
-{
-    overlay_stat_set(overlay_stat ^ stat);
-}
-
-void overlay_debug(void)
-{
-    debug_hex16(overlay_stat); debug("("); debug_dec(overlay_get_layer()); debug(")");
-}
-#endif
-
-action_t layer_switch_get_action(key_t key)
-{
-    action_t action;
-    action.code = ACTION_TRANSPARENT;
-
-#ifndef NO_ACTION_OVERLAY
-    /* overlay: top layer first */
-    for (int8_t i = 15; i >= 0; i--) {
-        if (overlay_stat & (1<<i)) {
-            action = action_for_key(i | OVERLAY_BIT, key);
-            if (action.code != ACTION_TRANSPARENT) {
-                return action;
-            }
-        }
-    }
-#endif
-
-#ifndef NO_ACTION_KEYMAP
-    /* keymap: top layer first */
-    for (int8_t i = 15; i >= 0; i--) {
-        if (keymap_stat & (1<<i)) {
-            action = action_for_key(i, key);
-            if (action.code != ACTION_TRANSPARENT) {
-                return action;
-            }
-        }
-    }
-#endif
-
-    /* default layer */
-    action = action_for_key(default_layer, key);
-    return action;
-}
diff --git a/common/layer_switch.h b/common/layer_switch.h
deleted file mode 100644
index eb4cf61b..00000000
--- a/common/layer_switch.h
+++ /dev/null
@@ -1,110 +0,0 @@
-/*
-Copyright 2013 Jun Wako <wakojun@gmail.com>
-
-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/>.
-*/
-#ifndef LAYER_SWITCH_H
-#define LAYER_SWITCH_H
-
-#include <stdint.h>
-#include "keyboard.h"
-#include "action.h"
-
-
-/* overlays are asigned at layer 16-31 */
-#define OVERLAY_BIT      0x10
-#define OVERLAY_MASK     0x0F
-
-
-/*
- * Default Layer
- */
-/* base layer to fall back */
-extern uint8_t default_layer;
-void default_layer_set(uint8_t layer);
-
-
-/*
- * Keymap Layer
- */
-#ifndef NO_ACTION_KEYMAP
-extern uint16_t keymap_stat;
-/* return current active layer */
-uint8_t keymap_get_layer(void);
-void keymap_clear(void);
-void keymap_set(uint16_t stat);
-void keymap_move(uint8_t layer);
-void keymap_on(uint8_t layer);
-void keymap_off(uint8_t layer);
-void keymap_invert(uint8_t layer);
-/* bitwise operation */
-void keymap_or(uint16_t stat);
-void keymap_and(uint16_t stat);
-void keymap_xor(uint16_t stat);
-void keymap_debug(void);
-#else
-#define keymap_stat             0
-#define keymap_get_layer()
-#define keymap_clear()
-#define keymap_set(stat)
-#define keymap_move(layer)
-#define keymap_on(layer)
-#define keymap_off(layer)
-#define keymap_invert(layer)
-#define keymap_or(stat)
-#define keymap_and(stat)
-#define keymap_xor(stat)
-#define keymap_debug()
-#endif
-
-
-/*
- * Overlay Layer
- */
-#ifndef NO_ACTION_OVERLAY
-extern uint16_t overlay_stat;
-/* return current active layer */
-uint8_t overlay_get_layer(void);
-void overlay_clear(void);
-void overlay_set(uint16_t stat);
-void overlay_move(uint8_t layer);
-void overlay_on(uint8_t layer);
-void overlay_off(uint8_t layer);
-void overlay_invert(uint8_t layer);
-/* bitwise operation */
-void overlay_or(uint16_t stat);
-void overlay_and(uint16_t stat);
-void overlay_xor(uint16_t stat);
-void overlay_debug(void);
-#else
-#define overlay_stat            0
-#define overlay_get_layer()
-#define overlay_clear()
-#define overlay_set(stat)
-#define overlay_move(layer)
-#define overlay_on(layer)
-#define overlay_off(layer)
-#define overlay_invert(layer)
-#define overlay_or(stat)
-#define overlay_and(stat)
-#define overlay_xor(stat)
-#define overlay_debug()
-#endif
-
-
-
-/* return action depending on current layer status */
-action_t layer_switch_get_action(key_t key);
-
-#endif
diff --git a/common/util.c b/common/util.c
index ff1926d7..6d4d6bfd 100644
--- a/common/util.c
+++ b/common/util.c
@@ -38,6 +38,14 @@ uint8_t bitpop16(uint16_t bits)
     return c;
 }
 
+uint8_t bitpop32(uint32_t bits)
+{
+    uint8_t c;
+    for (c = 0; bits; c++)
+        bits &= bits - 1;
+    return c;
+}
+
 // most significant on-bit - return highest location of on-bit
 // NOTE: return 0 when bit0 is on or all bits are off
 uint8_t biton(uint8_t bits)
@@ -58,3 +66,14 @@ uint8_t biton16(uint16_t bits)
     if (bits >> 1) { bits >>= 1; n += 1;}
     return n;
 }
+
+uint8_t biton32(uint32_t bits)
+{
+    uint8_t n = 0;
+    if (bits >>16) { bits >>=16; n +=16;}
+    if (bits >> 8) { bits >>= 8; n += 8;}
+    if (bits >> 4) { bits >>= 4; n += 4;}
+    if (bits >> 2) { bits >>= 2; n += 2;}
+    if (bits >> 1) { bits >>= 1; n += 1;}
+    return n;
+}
diff --git a/common/util.h b/common/util.h
index 58b7fdf1..4b8b5ca3 100644
--- a/common/util.h
+++ b/common/util.h
@@ -30,7 +30,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 uint8_t bitpop(uint8_t bits);
 uint8_t bitpop16(uint16_t bits);
+uint8_t bitpop32(uint32_t bits);
+
 uint8_t biton(uint8_t bits);
 uint8_t biton16(uint16_t bits);
+uint8_t biton32(uint32_t bits);
 
 #endif
diff --git a/converter/pc98_usb/keymap.c b/converter/pc98_usb/keymap.c
index 279b2b60..3ab0a4db 100644
--- a/converter/pc98_usb/keymap.c
+++ b/converter/pc98_usb/keymap.c
@@ -21,7 +21,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "keycode.h"
 #include "action.h"
 #include "action_macro.h"
-#include "layer_switch.h"
 #include "util.h"
 #include "keymap.h"
 
@@ -165,10 +164,10 @@ void action_function(keyrecord_t *record, uint8_t id, uint8_t opt)
  * Fn actions
  */
 static const uint16_t PROGMEM fn_actions[] = {
-    ACTION_KEYMAP_TAP_TOGGLE(0),                 // FN0
-    ACTION_KEYMAP_TAP_KEY(1, KC_SLASH),          // FN1
-    ACTION_KEYMAP_TAP_KEY(2, KC_SCLN),           // FN2
-    ACTION_KEYMAP_MOMENTARY(2),                  // FN3
+    ACTION_LAYER_TAP_TOGGLE(0),                  // FN0
+    ACTION_LAYER_TAP_KEY(1, KC_SLASH),           // FN1
+    ACTION_LAYER_TAP_KEY(2, KC_SCLN),            // FN2
+    ACTION_LAYER_MOMENTARY(2),                   // FN3
     ACTION_MACRO(LBRACKET),                      // FN4
     ACTION_MACRO(RBRACKET),                      // FN5
     ACTION_MACRO(DUMMY),                         // FN6
@@ -183,29 +182,16 @@ static const uint16_t PROGMEM fn_actions[] = {
  * No need to edit.
  */
 #define KEYMAPS_SIZE    (sizeof(keymaps) / sizeof(keymaps[0]))
-#define OVERLAYS_SIZE   (sizeof(overlays) / sizeof(overlays[0]))
 #define FN_ACTIONS_SIZE (sizeof(fn_actions) / sizeof(fn_actions[0]))
 
 /* translates key to keycode */
 uint8_t keymap_key_to_keycode(uint8_t layer, key_t key)
 {
-    /* Overlay: 16-31(OVERLAY_BIT(0x10) | overlay_layer) */
-    if (layer & OVERLAY_BIT) {
-        layer &= OVERLAY_MASK;
-        if (layer < OVERLAYS_SIZE) {
-            return pgm_read_byte(&overlays[(layer)][(key.row)][(key.col)]);
-        } else {
-            return KC_TRANSPARENT;
-        }
-    } 
-    /* Keymap: 0-15 */
-    else {
-        if (layer < KEYMAPS_SIZE) {
-            return pgm_read_byte(&keymaps[(layer)][(key.row)][(key.col)]);
-        } else {
-            // fall back to layer 0
-            return pgm_read_byte(&keymaps[0][(key.row)][(key.col)]);
-        }
+    if (layer < KEYMAPS_SIZE) {
+        return pgm_read_byte(&keymaps[(layer)][(key.row)][(key.col)]);
+    } else {
+        // fall back to layer 0
+        return pgm_read_byte(&keymaps[0][(key.row)][(key.col)]);
     }
 }
 
diff --git a/converter/pc98_usb/matrix.c b/converter/pc98_usb/matrix.c
index d03aaf10..8833e0a8 100644
--- a/converter/pc98_usb/matrix.c
+++ b/converter/pc98_usb/matrix.c
@@ -93,10 +93,6 @@ RETRY:
 
 void matrix_init(void)
 {
-    print_enable = true;
-//    debug_enable = true;
-//    debug_matrix = true;
-
     PC98_RST_DDR |= (1<<PC98_RST_BIT);
     PC98_RDY_DDR |= (1<<PC98_RDY_BIT);
     PC98_RTY_DDR |= (1<<PC98_RTY_BIT);
diff --git a/doc/keymap.md b/doc/keymap.md
index ca48c6e5..474a706e 100644
--- a/doc/keymap.md
+++ b/doc/keymap.md
@@ -3,20 +3,20 @@ Keymap framework - how to define your keymap
 ***NOTE: This is not final version, may be inconsistent with source code and changed occasionally for a while.***
 
 ## 0. Keymap and layers
-**Keymap** is comprised of multiple layers of key layout, you can define **16** layers at most.
-**Layer** is an array of **keycodes** to define **actions** on each physical keys.
-respective layers can be validated simultaneously. Layers are indexed with 0 to 15 and higher layer has precedence.
+**Keymap** is comprised of multiple layers of key layout, you can define **32 layers** at most.
+**Layer** is an array of **keycodes** to define **actions** for each physical keys.
+respective layers can be validated simultaneously. Layers are indexed with 0 to 31 and higher layer has precedence.
 
-    Keymap with 16 Layers               Layer: array of Keycodes
-    ---------------------               ------------------------
-          stack of layers               content of layer
+    Keymap: 32 Layers                   Layer: Keycode matrix
+    -----------------                   ---------------------
+    stack of layers                     array_of_keycode[row][column]
            ____________ precedence               _______________________
           /           / | high                  / ESC / F1  / F2  / F3   ....
-      15 /___________// |                      /-----/-----/-----/-----
-      14 /___________// |                     / TAB /     /     /      ....
-      13 /___________/_ |                    /-----/-----/-----/-----
-       :  / : : : : : / |                   /LCtrl/     /     /      ....
-       3 /___________// |               :  /  :     :     :     :
+      31 /___________// |                      /-----/-----/-----/-----
+      30 /___________// |                     / TAB /  Q  /  W  /  E   ....
+      29 /___________/  |                    /-----/-----/-----/-----
+       :   _:_:_:_:_:__ |               :   /LCtrl/  A  /  S  /  D   ....
+       :  / : : : : : / |               :  /  :     :     :     :
        2 /___________// |               2 `--------------------------
        1 /___________// |               1 `--------------------------
        0 /___________/  V low           0 `--------------------------
@@ -25,42 +25,42 @@ respective layers can be validated simultaneously. Layers are indexed with 0 to
 
 ### 0.1 Keymap status
 Keymap has its state in two parameters:
-**`default_layer`** indicates a base keymap layer(0-15) which is always valid and to be referred, **`keymap_stat`** is 16bit variable which has current on/off status of layers on its each bit.
+**`default_layer`** indicates a base keymap layer(0-31) which is always valid and to be referred, **`keymap_stat`** is 16bit variable which has current on/off status of layers on its each bit.
 
 Keymap layer '0' is usually `default_layer` and which is the only valid layer and other layers is initially off after boot up firmware, though, you can configured them in `config.h`.
-To change `default_layer` will be useful when you want to switch key layout completely, say you use Colmak instead of Qwerty.
+To change `default_layer` will be useful when you switch key layout completely, say you want Colmak instead of Qwerty.
 
-    Initial state of Keymap         Change base layout              
-    -----------------------         ------------------              
-                                                                    
-      15                              15                            
-      14                              14                            
-      13                              13                            
-       :                               :                            
-       3                               3   ____________             
-       2   ____________                2  /           /             
-       1  /           /             ,->1 /___________/              
-    ,->0 /___________/              |  0                            
-    |                               |                               
-    `--- default_layer = 0          `--- default_layer = 1          
-         keymap_stat   = 0x0001          keymap_stat   = 0x0002     
+    Initial state of Keymap          Change base layout              
+    -----------------------          ------------------              
 
-On the other hand, you shall change `keymap_state` to overlay base layer with some layers for feature such as navigation keys, function key(F1-F12), media keys or special actions.
+      31                               31
+      30                               30
+      29                               29
+       :                                :
+       :                                :   ____________
+       2   ____________                 2  /           /
+       1  /           /              ,->1 /___________/
+    ,->0 /___________/               |  0
+    |                                |
+    `--- default_layer = 0           `--- default_layer = 1
+         layer_state   = 0x00000001       layer_state   = 0x00000002
+
+On the other hand, you shall change `layer_state` to overlay base layer with some layers for feature such as navigation keys, function key(F1-F12), media keys or special actions.
 
     Overlay feature layer
     ---------------------      bit|status
            ____________        ---+------
-      15  /           /        15 |   0
-      14 /___________// -----> 14 |   1
-      13 /___________/  -----> 13 |   1
-       :                        : |   
-       3   ____________         3 |   0
+      31  /           /        31 |   0
+      30 /___________// -----> 30 |   1
+      29 /___________/  -----> 29 |   1
+       :                        : |   :
+       :   ____________         : |   :
        2  /           /         2 |   0
     ,->1 /___________/  ----->  1 |   1
     |  0                        0 |   0
-    |                                 |
+    |                                 +
     `--- default_layer = 1            |
-         keymap_stat   = 0x6002 <-----'
+         layer_state   = 0x60000002 <-'
 
 
 
@@ -146,9 +146,9 @@ You can find other keymap definitions in file `keymap.c` located on project dire
     };
 
     static const uint16_t PROGMEM fn_actions[] = {
-        ACTION_KEYMAP_MOMENTARY(1),                  // FN0
-        ACTION_KEYMAP_TAP_KEY(2, KC_SCLN),           // FN1
-        ACTION_KEYMAP_TOGGLE(2),                     // FN2
+        ACTION_LAYER_MOMENTARY(1),                  // FN0
+        ACTION_LAYER_TAP_KEY(2, KC_SCLN),           // FN1
+        ACTION_LAYER_TOGGLE(2),                     // FN2
     };
 
 
@@ -192,7 +192,7 @@ There are 8 modifiers which has discrimination between left and right.
 - `KC_WSCH`, `KC_WHOM`, `KC_WBAK`, `KC_WFWD`, `KC_WSTP`, `KC_WREF`, `KC_WFAV` for web browser operation
 
 ### 1.5 Fn key
-`KC_FNnn` are keycodes for `Fn` key which not given any actions at the beginning unlike most of keycodes has its own inborn action. To use these keycodes in `KEYMAP` you need to assign action you want at first. Action of `Fn` key is defined in `fn_actions[]` and its index of the array is identical with number part of `KC_FNnn`. Thus `KC_FN0` keyocde indicates the action defined in first element of the array. ***32 `Fn` keys can be defined at most.***
+`KC_FNnn` are keycodes for `Fn` key which not given any actions at the beginning unlike most of keycodes has its own inborn action. To use these keycodes in `KEYMAP()` you need to assign action you want at first. Action of `Fn` key is defined in `fn_actions[]` and its index of the array is identical with number part of `KC_FNnn`. Thus `KC_FN0` keyocde indicates the action defined in first element of the array. ***32 `Fn` keys can be defined at most.***
 
 ### 1.6 Keycode Table
  See keycode table in [`doc/keycode.txt`](./keycode.txt) for description of keycodes.
@@ -203,130 +203,158 @@ There are 8 modifiers which has discrimination between left and right.
 
 
 ## 2. Action
-See [`common/action.h`](../common/action.h). Action is a **16bit code** and defines function to perform on events of a key like press, release, holding and tapping.
+See [`common/action_code.h`](../common/action_code.h). Action is a **16bit code** and defines function to perform on events of a key like press, release, holding and tapping.
 
-Most of keys just register 8bit scancode to host, but to support other complex features needs 16bit extended action codes internally. However, using 16bit action codes in keymap results in double size in memory against using jsut keycodes. To avoid this waste 8bit keycodes are used in `KEYMAP` instead of action codes.
+Most of keys just register 8bit scancode to host, but to support other complex features needs 16bit extended action codes internally. However, using 16bit action codes in keymap results in double size in memory compared to using jsut keycodes. To avoid this waste 8bit keycodes are used in `KEYMAP()` instead of action codes.
 
 ***You can just use keycodes of `Normal key`, `Modifier`, `Mousekey` and `System & Media key` in keymap*** to indicate corresponding actions instead of using action codes. While ***to use other special actions you should use keycode of `Fn` key defined in `fn_actions[]`.***
 
-Usually action codes are needed only when you want to use layer switching, or 
 
-### 2.1 Key action
+### 2.1 Key Action
 This is a simple action that registers scancodes(HID usage in fact) to host on press event of key and unregister on release.
 
+#### Parameters
++ **mods**: { ` MOD_LCTL`, ` MOD_LSFT`, ` MOD_LALT`, ` MOD_LGUI`,
+              ` MOD_RCTL`, ` MOD_RSFT`, ` MOD_RALT`, ` MOD_RGUI` }
++ **key**: keycode
+
+
 #### 2.1.1 Normal key and Modifier
-This action usually won't be used expressly because you can use keycodes in `KEYMAP()` instead.
-You can define `Key` action on *'A'* key and *'left shift'* modifier with:
+***This action usually won't be used expressly in keymap*** because you can just use keycodes in `KEYMAP()` instead.
+
+You can define these actions on *'A'* key and *'left shift'* modifier with:
 
     ACTION_KEY(KC_A)
-    ACTION_KEY(KC_LSHIFT)
+    ACTION_KEY(KC_LSFT)
 
 #### 2.1.2 Key with modifiers
 This action is comprised of strokes of modifiers and a key. `Macro` action is needed if you want more complex key strokes.
+
 Say you want to assign a key to `Shift + 1` to get charactor *'!'* or `Alt + Tab` to switch application windows.
 
-    ACTION_LMOD_KEY(KC_LSHIFT, KC_1)
-    ACTION_LMOD_KEY(KC_LALT, KC_TAB)
+    ACTION_MODS_KEY(MOD_LSFT, KC_1)
+    ACTION_MODS_KEY(MOD_LALT, KC_TAB)
 
-Or `Alt,Shift + Tab` can be defined. `ACTION_LMODS_KEY()` requires **4-bit modifier state** and a **keycode** as arguments. See `keycode.h` for `MOD_BIT()` macro.
+Or `Alt,Shift + Tab` can be defined. `ACTION_MODS_KEY(mods, key)` requires **4-bit modifier state** and a **keycode** as arguments. See `keycode.h` for `MOD_BIT()` macro.
 
-    ACTION_LMODS_KEY((MOD_BIT(KC_LALT) | MOD_BIT(KC_LSHIFT)), KC_TAB)
+    ACTION_MODS_KEY(MOD_LALT | MOD_LSFT, KC_TAB)
+
+#### 2.1.3 Multiple Modifiers
+Registers multiple modifiers with pressing a key. To specify multiple modifiers use `|`.
+
+    ACTION_MODS(MOD_ALT | MOD_LSFT)
+
+#### 2.1.3 Modifier with tap key
+Works as a modifier key while holding, but registers a key on tap(press and release quickly).
+
+
+    ACTION_MODS_TAP_KEY(MOD_RCTL, KC_ENT)
 
 
 
 ### 2.2 Layer Action
 These actions operate layers of keymap.
 
-Parameters:
-- layer: 0-15
-- on: { press | release | both }
+#### Parameters
+You can specify a **target layer** of action and **when the action is executed**. Some actions take a **bit value** for bitwise operation.
 
 
-#### 2.2.0 Default Layer
-`default_layer` is layer which always is valid and referred to when actions is not defined on other layers.
-
-##### Return to Default Layer
-Turns on only `default layer` with clearing other all layers.
-
-    ACTION_DEFAULT_LAYER
-
-##### Set Default Layer
-Sets 'default layer' to layer and turn it on.
-
-    ACTION_DEFAULT_LAYER_SET_TO(layer)
-    ACTION_DEFAULT_LAYER_SET(layer, on)
++ **layer**: `0`-`31`
++ **on**: { `ON_PRESS` | `ON_RELEASE` | `ON_BOTH` }
++ **bits**: 4-bit value and 1-bit mask bit
 
 
-#### 2.2.1 Keymap
-These actions operate layer status of keymap.
+#### 2.2.1 Default Layer
+Default Layer is a layer which always is valid and referred to when actions is not defined on other overlay layers.
 
-##### Momentary Switch
-Turns on layer momentary while holding, in other words turn on when key is pressed and off when released.
+This sets Default Layer to given parameter `layer` and activate it.
 
-    ACTION_KEYMAP_MOMENTARY(layer)
+    ACTION_DEFAULT_LAYER(layer)
 
 
-##### Toggle Switch
-Turns on layer on first type and turns off on next.
+#### 2.2.2 Momentary Switch
+Turns on `layer` momentarily while holding, in other words it activates when key is pressed and deactivate when released.
 
-    ACTION_KEYMAP_TOGGLE(layer)
+    ACTION_LAYER_MOMENTARY(layer)
 
 
-##### Momentary Switch with tap key
-Turns on layer momentary while holding but registers key on tap.
+#### 2.2.3 Toggle Switch
+Turns on `layer` with first type(press and release) and turns off with next.
 
-    ACTION_KEYMAP_TAP_KEY(layer, key)
+    ACTION_LAYER_TOGGLE(layer)
 
 
-##### Momentary Switch with tap toggle
-Turns on layer momentary while holding but toggles it with serial taps.
+#### 2.2.4 Momentary Switch with tap key
+Turns on `layer` momentary while holding, but registers key on tap(press and release quickly).
 
-    ACTION_KEYMAP_TAP_TOGGLE(layer)
+    ACTION_LAYER_TAP_KEY(layer, key)
 
 
-##### Invert layer
-Inverts current layer state. If the layer is on it becomes off with this action.
+#### 2.2.5 Momentary Switch with tap toggle
+Turns on `layer` momentary while holding and toggles it with serial taps.
 
-    ACTION_KEYMAP_INV(layer, on)
+    ACTION_LAYER_TAP_TOGGLE(layer)
 
 
-##### Turn On layer
+#### 2.2.6 Invert state of layer
+Inverts current state of `layer`. If the layer is on it becomes off with this action.
+
+    ACTION_LAYER_INVERT(layer, on)
+
+
+#### 2.2.7 Turn On layer
 Turns on layer state.
 
-    ACTION_KEYMAP_ON(layer, on)
+    ACTION_LAYER_ON(layer, on)
 
-Turns on layer state on press and turn off on release. This is identical to **'Switch to layer'** action.
+Turns on layer state on press and turns off on release.
 
-    ACTION_KEYMAP_ON_OFF(layer)
+    ACTION_LAYER_ON_OFF(layer)
 
 
-##### Turn Off layer
+#### 2.2.8 Turn Off layer
 Turns off layer state.
 
-    ACTION_KEYMAP_OFF(layer, on)
+    ACTION_LAYER_OFF(layer, on)
+
+Turns off layer state on press and activates on release.
+
+    ACTION_LAYER_OFF_ON(layer)
 
 
-##### Set layer
+#### 2.2.9 Set layer
 Turn on layer only.
-`keymap_stat = (1<<layer) [layer: 0-15]`
+`layer_state = (1<<layer) [layer: 0-31]`
 
-    ACTION_KEYMAP_SET(layer, on)
+    ACTION_LAYER_SET(layer, on)
 
 Turns on layer only and clear all layer on release..
 
-    ACTION_KEYMAP_SET_CLEAR(layer)
+    ACTION_LAYER_SET_CLEAR(layer)
 
 
-#### 2.2.2 Overlay
-***TBD***
+#### 2.2.10 Bitwise operation
 
-In addition to actions of `Keymap` above these actions are also available.
+**part** indicates which part of 32bit layer state(0-7). **bits** is 5-bit value. **on** indicates when the action is executed.
 
-##### Invert 4bit layer states
-Invert 4bits out of 16bits of overlay status on both press and release.
-`overlay_stat = (overlay_stat ^ bits<<(shift*4)) [bits: 0-15, shift: 0-3]`
+    ACTION_LAYER_BIT_AND(part, bits, on)
+    ACTION_LAYER_BIT_OR(part, bits, on)
+    ACTION_LAYER_BIT_XOR(part, bits, on)
+    ACTION_LAYER_BIT_SET(part, bits, on)
 
-    ACTION_OVERLAY_INV4(bits, shift)
+These actions works with prameters as following code.
+
+    uint8_t shift = part*4;
+    uint32_t mask = (bits&0x10) ? ~(0xf<<shift) : 0;
+    uint32_t layer_state = layer_state <bitop> ((bits<<shift)|mask);
+
+
+Default Layer also has bitwise operations, they are executed when key is released.
+
+    ACTION_DEFAULT_LAYER_BIT_AND(part, bits)
+    ACTION_DEFAULT_LAYER_BIT_OR(part, bits)
+    ACTION_DEFAULT_LAYER_BIT_XOR(part, bits)
+    ACTION_DEFAULT_LAYER_BIT_SET(part, bits)
 
 
 
@@ -355,6 +383,7 @@ Invert 4bits out of 16bits of overlay status on both press and release.
 See `keyboard/hhkb/keymap.c` for sample.
 
 
+
 ### 2.4 Function action
 ***TBD***
 
@@ -403,88 +432,92 @@ See `keyboard/hhkb/keymap.c` for sample.
 
 
 
-## 4. Layer switching Example
+## 3. Layer switching Example
 There are some ways to switch layer with 'Layer' actions.
 
-### 4.1 Momentary switching
+### 3.1 Momentary switching
 Momentary switching changes layer only while holding Fn key.
 
-This action makes 'Layer 1' active(valid) on key press event and inactive on release event. Namely you can overlay a layer on base layer temporarily with this.
+This action makes 'Layer 1' active(valid) on key press event and inactive on release event. Namely you can overlay a layer on lower layers or default layer temporarily with this action.
 
-    ACTION_KEYMAP_MOMENTARY(1)
+    ACTION_LAYER_MOMENTARY(1)
 
 
-After switch actions of destination layer are perfomed.
-***Thus you shall need to place action to come back on destination layer***, or you will be stuck in destination layer without way to get back. Usually you need to palce same action or 'KC_TRNS` on destination layer to get back.
+Note that after switching on press the actions on destinaton layer(Layer 1) are perfomed.
+***Thus you shall need to place an action to go back on destination layer***, or you will be stuck in destination layer without way to get back. Usually you need to palce same action or 'KC_TRNS` on destination layer to get back.
 
 
-### 4.2 Toggle switching
-Toggle switching changes layer after press then release. With this you can keep staying on the layer until you press the key again to return.
+### 3.2 Toggle switching
+Toggle switching performed after releasing a key. With this action you can keep staying on the destination layer until you type the key again to return.
 
-This is toggle action of 'Layer 2'.
+This performs toggle switching action of 'Layer 2'.
 
-    ACTION_KEYMAP_TOGGLE(2)
+    ACTION_LAYER_TOGGLE(2)
 
 
 
-### 4.3 Momentary switching with Tap key
-These actions switch layer only while holding `Fn` key and register key on tap. **Tap** means to press and release key quickly.
+### 3.3 Momentary switching with Tap key
+These actions switch a layer only while holding a key but register the key on tap. **Tap** means to press and release a key quickly.
 
-    ACTION_KEYMAP_TAP_KEY(2, KC_SCLN)
+    ACTION_LAYER_TAP_KEY(2, KC_SCLN)
 
-With this you can place layer switching function on normal key like ';' without losing its original key register function.
+With this you can place a layer switching action on normal key like ';' without losing its original key register function. This action allows you to have layer switchig action without necessity of a dedicated key. It means you can have it even on home row of keyboard.
 
 
 
-### 4.4 Momentary switching with Tap Toggle
-This switches layer only while holding `Fn` key and toggle layer after several taps. **Tap** means to press and release key quickly.
+### 3.4 Momentary switching with Tap Toggle
+This switches layer only while holding a key but toggle layer with several taps. **Tap** means to press and release key quickly.
 
-    ACTION_KEYMAP_TAP_TOGGLE(1)
+    ACTION_LAYER_TAP_TOGGLE(1)
 
-Number of taps can be defined with `TAPPING_TOGGLE` in `config.h`, `5` by default.
+Number of taps can be configured with `TAPPING_TOGGLE` in `config.h`, `5` by default.
 
 
 
-## Tapping
-Tapping is to press and release key quickly. Tapping speed is determined with setting of `TAPPING_TERM`, which can be defined in `config.h`, 200ms by default.
+## 4. Tapping
+Tapping is to press and release a key quickly. Tapping speed is determined with setting of `TAPPING_TERM`, which can be defined in `config.h`, 200ms by default.
 
-### Tap Key
-This is feature to assign normal key action and modifier including `Fn` to just one physical key. This is a kind of [Dual role modifier][dual_role]. It works as modifier or `Fn` when holding a key but registers normal key when tapping.
+### 4.1 Tap Key
+This is a feature to assign normal key action and modifier including layer switching to just same one physical key. This is a kind of [Dual role modifier][dual_role]. It works as modifier when holding the key but registers normal key when tapping.
 
-Action for modifier with tap key.
+Modifier with tap key:
 
-    ACTION_LMODS_TAP_KEY(mods, key)
+    ACTION_MODS_TAP_KEY(MOD_RSFT, KC_GRV)
 
-Action for `Fn` with tap key.
+Layer switching with tap key:
 
-    ACTION_KEYMAP_TAP_KEY(layer, key)
+    ACTION_LAYER_TAP_KEY(2, KC_SCLN)
 
 [dual_role]: http://en.wikipedia.org/wiki/Modifier_key#Dual-role_modifier_keys
 
 
-### Tap Toggle
-This is feature to assign both toggle layer and momentary switch layer action to just one physical key. It works as mementary switch when holding a key but toggle switch when tapping.
+### 4.2 Tap Toggle
+This is a feature to assign both toggle layer and momentary switch layer action to just same one physical key. It works as mementary layer switch when holding a key but toggle switch with several taps.
 
-    ACTION_KEYMAP_TAP_TOGGLE(layer)
+    ACTION_LAYER_TAP_TOGGLE(1)
 
 
-### One Shot Modifier
-This adds oneshot feature to modifier key. 'One Shot Modifier' is one time modifier which has effect only on following one alpha key.
+### 4.3 One Shot Modifier
+This adds oneshot feature to modifier key. 'One Shot Modifier' is one time modifier which has effect only on following just one key.
 It works as normal modifier key when holding but oneshot modifier when tapping.
 
-    ACTION_LMODS_ONESHOT(mods)
+    ACTION_MODS_ONESHOT(MOD_LSFT)
 
-Say you want to type 'The', you have to push and hold Shift before type 't' then release Shift before type 'h' and 'e' or you'll get 'THe'. With One Shot Modifier you can tap Shift then type 't', 'h' and 'e' normally, you don't need to holding Shift key properly  here.
+Say you want to type 'The', you have to push and hold Shift before type 't' then release Shift before type 'h' and 'e' or you'll get 'THe'. With One Shot Modifier you can tap Shift then type 't', 'h' and 'e' normally, you don't need to holding Shift key properly here.
 
 
 
 
-## Legacy Keymap
-This was used in prior version and still works due to legacy support code in `common/keymap.c`. Legacy keymap doesn't support many of features that new keymap offers.
+## 5. Legacy Keymap
+This was used in prior version and still works due to legacy support code in `common/keymap.c`. Legacy keymap doesn't support many of features that new keymap offers. ***It is not recommended to use Legacy Keymap for new project.***
 
-In comparison with new keymap how to define Fn key is different. It uses two arrays `fn_layer[]` and `fn_keycode[]`. The index of arrays corresponds with postfix number of `Fn` key. Array `fn_layer[]` indicates destination layer to switch and `fn_keycode[]` has keycodes to send when tapping `Fn` key.
+To enable Legacy Keymap support define this macro in `config.h`.
 
-In following setting example, `Fn0`, `Fn1` and `Fn2` switch layer to 1, 2 and 2 respectively. `Fn2` registers `Space` key when tap while `Fn0` and `Fn1` doesn't send any key.
+    #define USE_LEGACY_KEYMAP
+
+Legacy Keymap uses two arrays `fn_layer[]` and `fn_keycode[]` to define Fn key. The index of arrays corresponds with postfix number of `Fn` key. Array `fn_layer[]` indicates destination layer to switch and `fn_keycode[]` has keycodes to send when tapping `Fn` key.
+
+In following setting example, `Fn0`, `Fn1` and `Fn2` switch layer to 1, 2 and 2 respectively. `Fn2` registers `Space` key when tapping while `Fn0` and `Fn1` doesn't send any key.
 
     static const uint8_t PROGMEM fn_layer[] = {
         1,              // Fn0
@@ -499,16 +532,25 @@ In following setting example, `Fn0`, `Fn1` and `Fn2` switch layer to 1, 2 and 2
     };
 
 
-## Terminology
-- keymap
-- layer
-- layout
-- key
-- keycode
-- scancode
-- action
-- layer transparency
-- layer precedence
-- register
-- tap
-- Fn key
+## 6. Terminology
+***TBD***
+### keymap
+is comprised of multiple layers.
+### layer
+is matrix of keycodes.
+### key
+is physical button on keyboard or logical switch on software.
+### keycode
+is codes used on firmware.
+### action
+is a function assigned on a key.
+### layer transparency
+Using transparent keycode one layer can refer key definition on other lower layer.
+### layer precedence
+Top layer has higher precedence than lower layers.
+### tapping
+is to press and release a key quickly.
+### Fn key
+is key which executes a special action like layer switching, mouse key, macro or etc.
+### dual role modifier
+<http://en.wikipedia.org/wiki/Modifier_key#Dual-role_modifier_keys>
diff --git a/keyboard/gh60/config.h b/keyboard/gh60/config.h
index fbe58708..567b126b 100644
--- a/keyboard/gh60/config.h
+++ b/keyboard/gh60/config.h
@@ -61,8 +61,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //#define NO_PRINT
 
 /* disable action features */
-//#define NO_ACTION_KEYMAP
-//#define NO_ACTION_OVERLAY
+//#define NO_ACTION_LAYER
 //#define NO_ACTION_TAPPING
 //#define NO_ACTION_ONESHOT
 //#define NO_ACTION_MACRO
diff --git a/keyboard/gh60/keymap.c b/keyboard/gh60/keymap.c
index d6af1696..edc1caf1 100644
--- a/keyboard/gh60/keymap.c
+++ b/keyboard/gh60/keymap.c
@@ -20,7 +20,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "keycode.h"
 #include "action.h"
 #include "action_macro.h"
-#include "layer_switch.h"
 #include "report.h"
 #include "host.h"
 #include "print.h"
@@ -91,7 +90,7 @@ static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
         ESC, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSPC, \
         TAB, Q,   W,   E,   R,   T,   Y,   U,   I,   O,   P,   LBRC,RBRC,BSLS, \
         LCTL,A,   S,   D,   F,   G,   H,   J,   K,   L,   FN2, QUOT,     ENT,  \
-        LSFT,Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, FN1,           RSFT, \
+        LSFT,Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, FN1,           FN9,  \
         LCTL,LGUI,LALT,          SPC,                     RALT,FN3, FN3, FN0),
     /* Keymap 1: colemak */
     KEYMAP_ANSI(
@@ -198,54 +197,38 @@ static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
         TRNS,TRNS,TRNS,          TRNS,                    TRNS,TRNS,TRNS,TRNS),
 };
 
-static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {};
-
 /*
  * Fn action definition
  */
 static const uint16_t PROGMEM fn_actions[] = {
-    [0] = ACTION_KEYMAP_MOMENTARY(4),
-    [1] = ACTION_KEYMAP_TAP_KEY(5, KC_SLASH),
-    [2] = ACTION_KEYMAP_TAP_KEY(6, KC_SCLN),
-    [3] = ACTION_KEYMAP_MOMENTARY(6),
-    [4] = ACTION_KEYMAP_MOMENTARY(7),   // to Layout selector
+    [0] = ACTION_LAYER_MOMENTARY(4),
+    [1] = ACTION_LAYER_TAP_KEY(5, KC_SLASH),
+    [2] = ACTION_LAYER_TAP_KEY(6, KC_SCLN),
+    [3] = ACTION_LAYER_MOMENTARY(6),
+    [4] = ACTION_LAYER_MOMENTARY(7),   // to Layout selector
     [5] = ACTION_DEFAULT_LAYER_SET(0),  // set qwerty layout
     [6] = ACTION_DEFAULT_LAYER_SET(1),  // set colemak layout
     [7] = ACTION_DEFAULT_LAYER_SET(2),  // set dvorak layout
     [8] = ACTION_DEFAULT_LAYER_SET(3),  // set workman layout
+    [9] = ACTION_MODS_TAP_KEY(MOD_RSFT, KC_GRV),
 };
 #endif
 
 
 
 #define KEYMAPS_SIZE    (sizeof(keymaps) / sizeof(keymaps[0]))
-#define OVERLAYS_SIZE   (sizeof(overlays) / sizeof(overlays[0]))
 #define FN_ACTIONS_SIZE (sizeof(fn_actions) / sizeof(fn_actions[0]))
 
 /* translates key to keycode */
 uint8_t keymap_key_to_keycode(uint8_t layer, key_t key)
 {
-    /* Overlay: 16-31(OVERLAY_BIT(0x10) | overlay_layer) */
-    if (layer & OVERLAY_BIT) {
-        layer &= OVERLAY_MASK;
-        if (layer < OVERLAYS_SIZE) {
-            return pgm_read_byte(&overlays[(layer)][(key.row)][(key.col)]);
-        } else {
-            // XXX: this may cuaes bootlaoder_jump incositent fail.
-            //debug("key_to_keycode: overlay "); debug_dec(layer); debug(" is invalid.\n");
-            return KC_TRANSPARENT;
-        }
-    } 
-    /* Keymap: 0-15 */
-    else {
-        if (layer < KEYMAPS_SIZE) {
-            return pgm_read_byte(&keymaps[(layer)][(key.row)][(key.col)]);
-        } else {
-            // XXX: this may cuaes bootlaoder_jump incositent fail.
-            //debug("key_to_keycode: base "); debug_dec(layer); debug(" is invalid.\n");
-            // fall back to layer 0
-            return pgm_read_byte(&keymaps[0][(key.row)][(key.col)]);
-        }
+    if (layer < KEYMAPS_SIZE) {
+        return pgm_read_byte(&keymaps[(layer)][(key.row)][(key.col)]);
+    } else {
+        // XXX: this may cuaes bootlaoder_jump inconsistent fail.
+        //debug("key_to_keycode: base "); debug_dec(layer); debug(" is invalid.\n");
+        // fall back to layer 0
+        return pgm_read_byte(&keymaps[0][(key.row)][(key.col)]);
     }
 }
 
diff --git a/keyboard/gh60/keymap_plain.h b/keyboard/gh60/keymap_plain.h
index 85331715..52d11256 100644
--- a/keyboard/gh60/keymap_plain.h
+++ b/keyboard/gh60/keymap_plain.h
@@ -1,10 +1,9 @@
 static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
-    /* Keymap 0: qwerty */
+    /* 0: qwerty */
     KEYMAP(ESC, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSPC, \
            TAB, Q,   W,   E,   R,   T,   Y,   U,   I,   O,   P,   LBRC,RBRC,BSLS, \
            CAPS,A,   S,   D,   F,   G,   H,   J,   K,   L,   SCLN,QUOT,NO,  ENT,  \
            LSFT,NO,  Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, SLSH,NO,  RSFT, \
            LCTL,LGUI,LALT,          SPC,                     RALT,RGUI,APP, RCTL),
 };
-static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {};
 static const uint16_t PROGMEM fn_actions[] = {};
diff --git a/keyboard/gh60/keymap_poker.h b/keyboard/gh60/keymap_poker.h
index 3e0921ad..16429994 100644
--- a/keyboard/gh60/keymap_poker.h
+++ b/keyboard/gh60/keymap_poker.h
@@ -1,49 +1,47 @@
 static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
-    /* Keymap 0: qwerty */
+    /* 0: qwerty */
     KEYMAP_ANSI(
         GRV, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSPC, \
         TAB, Q,   W,   E,   R,   T,   Y,   U,   I,   O,   P,   LBRC,RBRC,BSLS, \
         CAPS,A,   S,   D,   F,   G,   H,   J,   K,   L,   SCLN,QUOT,     ENT,  \
         LSFT,Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, SLSH,          RSFT, \
         LCTL,LGUI,LALT,          SPC,                     FN0, RGUI,APP, RCTL),
-    /* Keymap 1: colemak */
+    /* 1: colemak */
     KEYMAP_ANSI(
         GRV, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSPC, \
         TAB, Q,   W,   F,   P,   G,   J,   L,   U,   Y,   SCLN,LBRC,RBRC,BSLS, \
         BSPC,A,   R,   S,   T,   D,   H,   N,   E,   I,   O,   QUOT,     ENT,  \
         LSFT,Z,   X,   C,   V,   B,   K,   M,   COMM,DOT, SLSH,          RSFT, \
         LCTL,LGUI,LALT,          SPC,                     FN0, RGUI,APP, RCTL),
-    /* Keymap 2: dvorak */
+    /* 2: dvorak */
     KEYMAP_ANSI(
         GRV, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   LBRC,RBRC,BSPC, \
         TAB, QUOT,COMM,DOT, P,   Y,   F,   G,   C,   R,   L,   SLSH,EQL, BSLS, \
         CAPS,A,   O,   E,   U,   I,   D,   H,   T,   N,   S,   MINS,     ENT,  \
         LSFT,SCLN,Q,   J,   K,   X,   B,   M,   W,   V,   Z,             RSFT, \
         LCTL,LGUI,LALT,          SPC,                     FN0, RGUI,APP, RCTL),
-    /* Keymap: workman */
+    /* 3: workman */
     KEYMAP_ANSI(
         GRV, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSPC, \
         TAB, Q,   D,   R,   W,   B,   J,   F,   U,   P,   SCLN,LBRC,RBRC,BSLS, \
         BSPC,A,   S,   H,   T,   G,   Y,   N,   E,   O,   I,   QUOT,     ENT,  \
         LSFT,Z,   X,   M,   C,   V,   K,   L,   COMM,DOT, SLSH,          RSFT, \
         LCTL,LGUI,LALT,          SPC,                     FN0, RGUI,APP, RCTL),
-};
-static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
-    /* Overlay 0: Poker with Arrow */
+    /* 4: Poker with Arrow */
     KEYMAP_ANSI(
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,     TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,          UP,   \
         TRNS,TRNS,TRNS,          TRNS,                    TRNS,LEFT,DOWN,RGHT),
-    /* Overlay 1: Poker with Esc */
+    /* 5: Poker with Esc */
     KEYMAP_ANSI(
         ESC, TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,     TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,          TRNS, \
         TRNS,TRNS,TRNS,          TRNS,                    TRNS,TRNS,TRNS,TRNS),
-    /* Overlay 2: Poker Fn
+    /* 6: Poker Fn
      * ,-----------------------------------------------------------.
      * |Esc| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|       |
      * |-----------------------------------------------------------|
@@ -66,7 +64,7 @@ static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
         TRNS,LEFT,DOWN,RGHT,TRNS,TRNS,PSCR,SLCK,PAUS,TRNS,FN3, END,      TRNS, \
         TRNS,DEL, TRNS,WHOM,MUTE,VOLU,VOLD,TRNS,PGUP,PGDN,DEL,           TRNS, \
         TRNS,TRNS,TRNS,          FN1,                     TRNS,TRNS,TRNS,TRNS),
-    /* Overlay 3: Layout selector
+    /* 7: Layout selector
      * ,-----------------------------------------------------------.
      * | Lq| Lc| Ld| Lw|   |   |   |   |   |   |   |   |   |       |
      * |-----------------------------------------------------------|
@@ -92,11 +90,11 @@ static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
 };
 static const uint16_t PROGMEM fn_actions[] = {
     /* Poker Layout */
-    [0] = ACTION_OVERLAY_MOMENTARY(2),  // to Fn overlay
-    [1] = ACTION_OVERLAY_TOGGLE(0),     // toggle arrow overlay
-    [2] = ACTION_OVERLAY_TOGGLE(1),     // toggle Esc overlay
-    [3] = ACTION_RMODS_KEY(MOD_BIT(KC_RCTL)|MOD_BIT(KC_RSFT), KC_ESC), // Task(RControl,RShift+Esc)
-    [4] = ACTION_OVERLAY_MOMENTARY(3),  // to Layout selector
+    [0] = ACTION_LAYER_MOMENTARY(6),  // to Fn overlay
+    [1] = ACTION_LAYER_TOGGLE(4),     // toggle arrow overlay
+    [2] = ACTION_LAYER_TOGGLE(5),     // toggle Esc overlay
+    [3] = ACTION_MODS_KEY(MOD_RCTL|MOD_RSFT, KC_ESC), // Task(RControl,RShift+Esc)
+    [4] = ACTION_LAYER_MOMENTARY(7),  // to Layout selector
     [5] = ACTION_DEFAULT_LAYER_SET(0),  // set qwerty layout
     [6] = ACTION_DEFAULT_LAYER_SET(1),  // set colemak layout
     [7] = ACTION_DEFAULT_LAYER_SET(2),  // set dvorak layout
diff --git a/keyboard/gh60/keymap_poker_bit.h b/keyboard/gh60/keymap_poker_bit.h
index 982632d0..1b498351 100644
--- a/keyboard/gh60/keymap_poker_bit.h
+++ b/keyboard/gh60/keymap_poker_bit.h
@@ -2,37 +2,35 @@
 // Fn + Esc = `
 // Fn + {left, down, up, right}  = {home, pgdown, pgup, end}
 static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
-    /* Keymap 0: qwerty */
+    /* 0: qwerty */
     KEYMAP_ANSI(
         GRV, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSPC, \
         TAB, Q,   W,   E,   R,   T,   Y,   U,   I,   O,   P,   LBRC,RBRC,BSLS, \
         LCTL,A,   S,   D,   F,   G,   H,   J,   K,   L,   SCLN,QUOT,     ENT,  \
         LSFT,Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, SLSH,          RSFT, \
         LCTL,LGUI,LALT,          SPC,                     FN0, RGUI,APP, RCTL),
-};
-static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
-    /* Overlay 0: Poker Default + Fn'd */
-    KEYMAP_ANSI(
+    /* 4: Poker Default + Fn'd */
+    [4] = KEYMAP_ANSI(
         TRNS,F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, TRNS, \
         CAPS,FN2, UP,  TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,CALC,TRNS,HOME,INS, TRNS, \
         TRNS,LEFT,DOWN,RGHT,TRNS,TRNS,PSCR,SLCK,PAUS,TRNS,FN4, END,      TRNS, \
         TRNS,DEL, TRNS,WHOM,MUTE,VOLU,VOLD,TRNS,PGUP,PGDN,DEL,           TRNS, \
         TRNS,TRNS,TRNS,          FN1,                     TRNS,TRNS,TRNS,TRNS),
-    /* Overlay 1: Poker with Arrow */
+    /* 5: Poker with Arrow */
     KEYMAP_ANSI(
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,     TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,          PGUP, \
         TRNS,TRNS,TRNS,          TRNS,                    FN3, HOME,PGDN,END),
-    /* Overlay 2: Poker with Esc */
+    /* 6: Poker with Esc */
     KEYMAP_ANSI(
         ESC, TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,     TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,          TRNS, \
         TRNS,TRNS,TRNS,          TRNS,                    TRNS,TRNS,TRNS,TRNS),
-    /* Overlay 3: Poker with Arrow + Fn'd */
+    /* 7: Poker with Arrow + Fn'd */
     KEYMAP_ANSI(
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
@@ -42,9 +40,9 @@ static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
 };
 static const uint16_t PROGMEM fn_actions[] = {
     /* Poker Layout */
-    [0] = ACTION_OVERLAY_INV4(0b0101, 0),        // Poker Fn(with fix for Esc)
-    [1] = ACTION_OVERLAY_TOGGLE(1),              // Poker Arrow toggle
-    [2] = ACTION_OVERLAY_TOGGLE(2),              // Poker Esc toggle
-    [3] = ACTION_OVERLAY_INV4(0b1101, 0),        // Poker Fn(with fix for Arrow)
-    [4] = ACTION_RMODS_KEY(MOD_BIT(KC_RCTL)|MOD_BIT(KC_RSFT), KC_ESC), // FN3 Task(RControl,RShift+Esc)
+    [0] = ACTION_LAYER_BIT_XOR(1, 0b0101, ON_BOTH),   // Poker Fn(with fix for Esc)
+    [1] = ACTION_LAYER_TOGGLE(5),                     // Poker Arrow toggle
+    [2] = ACTION_LAYER_TOGGLE(6),                     // Poker Esc toggle
+    [3] = ACTION_LAYER_BIT_XOR(1, 0b1101, ON_BOTH),   // Poker Fn(with fix for Arrow)
+    [4] = ACTION_MODS_KEY(MOD_RCTL|MOD_RSFT, KC_ESC), // FN3 Task(RControl,RShift+Esc)
 };
diff --git a/keyboard/gh60/keymap_poker_set.h b/keyboard/gh60/keymap_poker_set.h
index eaaf3159..e1e4d80e 100644
--- a/keyboard/gh60/keymap_poker_set.h
+++ b/keyboard/gh60/keymap_poker_set.h
@@ -2,58 +2,56 @@
 // Fn + Esc = `
 // Fn + {left, down, up, right}  = {home, pgdown, pgup, end}
 static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
-    /* Keymap 0: qwerty */
+    /* 0: qwerty */
     KEYMAP_ANSI(
         GRV, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSPC, \
         TAB, Q,   W,   E,   R,   T,   Y,   U,   I,   O,   P,   LBRC,RBRC,BSLS, \
         LCTL,A,   S,   D,   F,   G,   H,   J,   K,   L,   SCLN,QUOT,     ENT,  \
         LSFT,Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, SLSH,          RSFT, \
         LCTL,LGUI,LALT,          SPC,                     FN0, RGUI,APP, RCTL),
-};
-static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
-    /* Overlay 0: Poker with Arrow */
+    /* 1: Poker with Arrow */
     KEYMAP_ANSI(
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,     TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,          UP,   \
         TRNS,TRNS,TRNS,          TRNS,                    FN1, LEFT,DOWN,RGHT),
-    /* Overlay 1: Poker with Esc */
+    /* 2: Poker with Esc */
     KEYMAP_ANSI(
         ESC, TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,     TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,          TRNS, \
         TRNS,TRNS,TRNS,          TRNS,                    FN2, TRNS,TRNS,TRNS),
-    /* Overlay 2: Poker with Arrow and Esc */
+    /* 3: Poker with Arrow and Esc */
     KEYMAP_ANSI(
         ESC, TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,     TRNS, \
         TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,          UP,   \
         TRNS,TRNS,TRNS,          TRNS,                    FN3, LEFT,DOWN,RGHT),
-    /* Overlay 3: Poker Fn'd */
+    /* 4: Poker Fn'd */
     KEYMAP_ANSI(
         ESC, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, TRNS, \
         TRNS,FN6, UP,  TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,CALC,TRNS,HOME,INS, TRNS, \
         TRNS,LEFT,DOWN,RGHT,TRNS,TRNS,PSCR,SLCK,PAUS,TRNS,FN8, END,      TRNS, \
         TRNS,DEL, TRNS,WHOM,MUTE,VOLU,VOLD,TRNS,PGUP,PGDN,DEL,           TRNS, \
         TRNS,TRNS,TRNS,          FN5,                     FN4, TRNS,TRNS,TRNS),
-    /* Overlay 4: Poker Fn'd arrow */
+    /* 5: Poker Fn'd arrow */
     KEYMAP_ANSI(
         ESC, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, TRNS, \
         TRNS,FN7, UP,  TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,CALC,TRNS,HOME,INS, TRNS, \
         TRNS,LEFT,DOWN,RGHT,TRNS,TRNS,PSCR,SLCK,PAUS,TRNS,FN8, END,      TRNS, \
         TRNS,DEL, TRNS,WHOM,MUTE,VOLU,VOLD,TRNS,PGUP,PGDN,DEL,           PGUP, \
         TRNS,TRNS,TRNS,          FN4,                     FN5, HOME,PGDN,END),
-    /* Overlay 5: Poker Fn'd Esc */
+    /* 6: Poker Fn'd Esc */
     KEYMAP_ANSI(
         GRV, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, TRNS, \
         TRNS,FN4, UP,  TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,CALC,TRNS,HOME,INS, TRNS, \
         TRNS,LEFT,DOWN,RGHT,TRNS,TRNS,PSCR,SLCK,PAUS,TRNS,FN8, END,      TRNS, \
         TRNS,DEL, TRNS,WHOM,MUTE,VOLU,VOLD,TRNS,PGUP,PGDN,DEL,           TRNS, \
         TRNS,TRNS,TRNS,          FN7,                     FN6, TRNS,TRNS,TRNS),
-    /* Overlay 6: Poker Fn'd Arrow + Esc */
+    /* 7: Poker Fn'd Arrow + Esc */
     KEYMAP_ANSI(
         GRV, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, TRNS, \
         TRNS,FN5, UP,  TRNS,TRNS,TRNS,TRNS,TRNS,TRNS,CALC,TRNS,HOME,INS, TRNS, \
@@ -67,15 +65,16 @@ static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {
  */
 static const uint16_t PROGMEM fn_actions[] = {
     /* Poker Layout */
-    [0] = ACTION_OVERLAY_SET(3, ON_PRESS),     // FN0 move to Fn'd             when press
-    [1] = ACTION_OVERLAY_SET(4, ON_PRESS),     // FN1 move to Fn'd arrow       when press
-    [2] = ACTION_OVERLAY_SET(5, ON_PRESS),     // FN2 move to Fn'd Esc         when press
-    [3] = ACTION_OVERLAY_SET(6, ON_PRESS),     // FN3 move to Fn'd arrow + Esc when press
+    [0] = ACTION_LAYER_SET(4, ON_PRESS),     // FN0 move to Fn'd             when press
+    [1] = ACTION_LAYER_SET(5, ON_PRESS),     // FN1 move to Fn'd arrow       when press
+    [2] = ACTION_LAYER_SET(6, ON_PRESS),     // FN2 move to Fn'd Esc         when press
+    [3] = ACTION_LAYER_SET(7, ON_PRESS),     // FN3 move to Fn'd arrow + Esc when press
 
-    [4] = ACTION_OVERLAY_CLEAR(ON_RELEASE),    // FN4 clear overlay            when release
-    [5] = ACTION_OVERLAY_SET(0, ON_RELEASE),   // FN5 move to arrow            when release
-    [6] = ACTION_OVERLAY_SET(1, ON_RELEASE),   // FN6 move to Esc              when release
-    [7] = ACTION_OVERLAY_SET(2, ON_RELEASE),   // FN7 move to arrow + Esc      when release
+    //[4] = ACTION_LAYER_CLEAR(ON_RELEASE),    // FN4 clear overlay            when release
+    [4] = ACTION_LAYER_SET(0, ON_RELEASE),   // FN4 clear overlay            when release
+    [5] = ACTION_LAYER_SET(1, ON_RELEASE),   // FN5 move to arrow            when release
+    [6] = ACTION_LAYER_SET(2, ON_RELEASE),   // FN6 move to Esc              when release
+    [7] = ACTION_LAYER_SET(3, ON_RELEASE),   // FN7 move to arrow + Esc      when release
 
-    [8] = ACTION_RMODS_KEY(MOD_BIT(KC_RCTL)|MOD_BIT(KC_RSFT), KC_ESC), // FN8 Task(RControl,RShift+Esc)
+    [8] = ACTION_MODS_KEY(MOD_RCTL|MOD_RSFT, KC_ESC), // FN8 Task(RControl,RShift+Esc)
 };
diff --git a/keyboard/hhkb/config.h b/keyboard/hhkb/config.h
index 6e26edbe..9df86126 100644
--- a/keyboard/hhkb/config.h
+++ b/keyboard/hhkb/config.h
@@ -74,8 +74,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //#define NO_PRINT
 
 /* disable action features */
-//#define NO_ACTION_KEYMAP
-//#define NO_ACTION_OVERLAY
+//#define NO_ACTION_LAYER
 //#define NO_ACTION_TAPPING
 //#define NO_ACTION_ONESHOT
 //#define NO_ACTION_MACRO
diff --git a/keyboard/hhkb/keymap.c b/keyboard/hhkb/keymap.c
index 094d33af..7afbdbec 100644
--- a/keyboard/hhkb/keymap.c
+++ b/keyboard/hhkb/keymap.c
@@ -186,17 +186,14 @@ enum macro_id {
  * Fn action definition
  */
 static const uint16_t PROGMEM fn_actions[] = {
-    [0] = ACTION_DEFAULT_LAYER,                        // Default layer(not used)
-//  [1] = ACTION_KEYMAP(1),                            // HHKB layer
-    [1] = ACTION_KEYMAP_TAP_TOGGLE(1),                 // HHKB layer(toggle with 5 taps)
-    [2] = ACTION_KEYMAP_TAP_KEY(2, KC_SLASH),          // Cursor layer with Slash*
-    [3] = ACTION_KEYMAP_TAP_KEY(3, KC_SCLN),           // Mousekey layer with Semicolon*
-    [4] = ACTION_RMOD_TAP_KEY(KC_RCTL, KC_ENT),        // RControl with tap Enter*
-    [5] = ACTION_LMOD_ONESHOT(KC_LSFT),                // Oneshot Shift*
-//  [6] = ACTION_KEYMAP_TAP_KEY(4, KC_SPC),            // Half-qwerty layer with Space
-    [6] = ACTION_KEYMAP_TAP_KEY(5, KC_SPC),            // Mousekey layer with Space
-//  [7] = ACTION_KEYMAP(3),                            // Mousekey layer
-    [7] = ACTION_KEYMAP_TOGGLE(3),                     // Mousekey layer(toggle)
+    [0] = ACTION_DEFAULT_LAYER_SET(0),                // Default layer(not used)
+    [1] = ACTION_LAYER_TAP_TOGGLE(1),                 // HHKB layer(toggle with 5 taps)
+    [2] = ACTION_LAYER_TAP_KEY(2, KC_SLASH),          // Cursor layer with Slash*
+    [3] = ACTION_LAYER_TAP_KEY(3, KC_SCLN),           // Mousekey layer with Semicolon*
+    [4] = ACTION_MODS_TAP_KEY(MOD_RCTL, KC_ENT),      // RControl with tap Enter*
+    [5] = ACTION_MODS_ONESHOT(MOD_LSFT),              // Oneshot Shift*
+    [6] = ACTION_LAYER_TAP_KEY(5, KC_SPC),            // Mousekey layer with Space
+    [7] = ACTION_LAYER_TOGGLE(3),                     // Mousekey layer(toggle)
 
 //  [8] = ACTION_LMOD_TAP_KEY(KC_LCTL, KC_BSPC),       // LControl with tap Backspace
 //  [9] = ACTION_LMOD_TAP_KEY(KC_LCTL, KC_ESC),        // LControl with tap Esc
diff --git a/keyboard/hid_liber/keymap.c b/keyboard/hid_liber/keymap.c
index f3d6bfa2..609edb5e 100644
--- a/keyboard/hid_liber/keymap.c
+++ b/keyboard/hid_liber/keymap.c
@@ -24,7 +24,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "keycode.h"
 #include "action.h"
 #include "action_macro.h"
-#include "layer_switch.h"
 #include "report.h"
 #include "host.h"
 #include "print.h"
@@ -160,8 +159,6 @@ static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
 
 };
 
-static const uint8_t PROGMEM overlays[][MATRIX_ROWS][MATRIX_COLS] = {};
-
 /*
  * Fn action definition
  */
@@ -179,33 +176,15 @@ static const uint16_t PROGMEM fn_actions[] = {
 #endif 
 
 #define KEYMAPS_SIZE    (sizeof(keymaps) / sizeof(keymaps[0]))
-#define OVERLAYS_SIZE   (sizeof(overlays) / sizeof(overlays[0]))
 #define FN_ACTIONS_SIZE (sizeof(fn_actions) / sizeof(fn_actions[0]))
 
 /* translates key to keycode */
 uint8_t keymap_key_to_keycode(uint8_t layer, key_t key)
 {
-    /* Overlay: 16-31(OVERLAY_BIT(0x10) | overlay_layer) */
-    if (layer & OVERLAY_BIT) {
-        layer &= OVERLAY_MASK;
-        if (layer < OVERLAYS_SIZE) {
-            return pgm_read_byte(&overlays[(layer)][(key.row)][(key.col)]);
-        } else {
-            // XXX: this may cuaes bootlaoder_jump incositent fail.
-            //debug("key_to_keycode: overlay "); debug_dec(layer); debug(" is invalid.\n");
-            return KC_TRANSPARENT;
-        }
-    } 
-    /* Keymap: 0-15 */
-    else {
-        if (layer < KEYMAPS_SIZE) {
-            return pgm_read_byte(&keymaps[(layer)][(key.row)][(key.col)]);
-        } else {
-            // XXX: this may cuaes bootlaoder_jump incositent fail.
-            //debug("key_to_keycode: base "); debug_dec(layer); debug(" is invalid.\n");
-            // fall back to layer 0
-            return pgm_read_byte(&keymaps[0][(key.row)][(key.col)]);
-        }
+    if (layer < KEYMAPS_SIZE) {
+        return pgm_read_byte(&keymaps[(layer)][(key.row)][(key.col)]);
+    } else {
+        return pgm_read_byte(&keymaps[0][(key.row)][(key.col)]);
     }
 }