diff --git a/hbk/Makefile b/hbk/Makefile
new file mode 100644
index 00000000..e03b45e3
--- /dev/null
+++ b/hbk/Makefile
@@ -0,0 +1,54 @@
+# Target file name (without extension).
+TARGET = hbk
+
+# Directory common source filess exist
+COMMON_DIR = ..
+
+# Directory keyboard dependent files exist
+TARGET_DIR = .
+
+# keyboard dependent files
+SRC =	main.c \
+	keymap.c \
+	matrix.c \
+	led.c
+
+CONFIG_H = config.h
+
+
+# MCU name, you MUST set this to match the board you are using
+# type "make clean" after changing this, so all files will be rebuilt
+#MCU = at90usb162       # Teensy 1.0
+MCU = atmega32u4       # Teensy 2.0
+#MCU = at90usb646       # Teensy++ 1.0
+#MCU = at90usb1286      # Teensy++ 2.0
+
+
+# Processor frequency.
+#   Normally the first thing your program should do is set the clock prescaler,
+#   so your program will run at the correct speed.  You should also set this
+#   variable to same clock speed.  The _delay_ms() macro uses this, and many
+#   examples use this variable to calculate timings.  Do not add a "UL" here.
+F_CPU = 16000000
+
+
+# Build Options
+#   comment out to disable the options.
+#
+MOUSEKEY_ENABLE = yes	# Mouse keys
+#PS2_MOUSE_ENABLE = yes	# PS/2 mouse(TrackPoint) support
+EXTRAKEY_ENABLE = yes	# Audio control and System control
+#NKRO_ENABLE = yes	# USB Nkey Rollover
+
+
+
+#---------------- Programming Options --------------------------
+#PROGRAM_CMD = teensy_loader_cli -mmcu=$(MCU) -w -v $(TARGET).hex
+PROGRAM_CMD = /opt/dfu-programmer-0.5.2/bin/dfu-programmer $(MCU) erase && \
+	      /opt/dfu-programmer-0.5.2/bin/dfu-programmer $(MCU) flash $(TARGET).hex && \
+	      /opt/dfu-programmer-0.5.2/bin/dfu-programmer $(MCU) start
+
+
+
+include $(COMMON_DIR)/pjrc.mk
+include $(COMMON_DIR)/common.mk
diff --git a/hbk/config.h b/hbk/config.h
new file mode 100644
index 00000000..5262399d
--- /dev/null
+++ b/hbk/config.h
@@ -0,0 +1,52 @@
+/*
+Copyright 2012 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 CONFIG_H
+#define CONFIG_H
+
+/* controller configuration */
+#include "controller_teensy.h"
+
+#define VENDOR_ID       0xFEED
+#define PRODUCT_ID      0xBB00
+#define MANUFACTURER    t.m.k.
+#define PRODUCT         Happy Buckling Keyboard
+#define DESCRIPTION     mod version of IBM Model M keyboard
+
+
+/* matrix size */
+#define MATRIX_ROWS 12
+#define MATRIX_COLS 8
+/* define if matrix has ghost */
+#define MATRIX_HAS_GHOST
+/* Set 0 if need no debouncing */
+#define DEBOUNCE    10
+
+
+/* key combination for command */
+#define IS_COMMAND() ( \
+    keyboard_report->mods == (MOD_BIT(KB_LSHIFT) | MOD_BIT(KB_LCTRL) | MOD_BIT(KB_LALT) | MOD_BIT(KB_LGUI)) || \
+    keyboard_report->mods == (MOD_BIT(KB_LALT) | MOD_BIT(KB_RALT)) \
+)
+
+
+/* mouse keys */
+#ifdef MOUSEKEY_ENABLE
+#   define MOUSEKEY_DELAY_TIME 128
+#endif
+
+#endif
diff --git a/hbk/controller_teensy.h b/hbk/controller_teensy.h
new file mode 100644
index 00000000..1b161136
--- /dev/null
+++ b/hbk/controller_teensy.h
@@ -0,0 +1,27 @@
+/*
+Copyright 2011 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 TEENSY_H
+#define TEENSY_H 1
+
+// for Teensy/Teensy++ 2.0
+#undef  DEBUG_LED
+#define DEBUG_LED_CONFIG
+#define DEBUG_LED_ON
+#define DEBUG_LED_OFF
+
+#endif
diff --git a/hbk/keymap.c b/hbk/keymap.c
new file mode 100644
index 00000000..1de317c9
--- /dev/null
+++ b/hbk/keymap.c
@@ -0,0 +1,231 @@
+/*
+Copyright 2012 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/>.
+*/
+
+/* 
+ * Keymap for Macway mod
+ */
+#include <stdint.h>
+#include <stdbool.h>
+#include <avr/pgmspace.h>
+#include "usb_keycodes.h"
+#include "print.h"
+#include "debug.h"
+#include "util.h"
+#include "keymap.h"
+
+
+/*
+ * Layout: 59key
+ * ,-----------------------------------------------------------.
+ * |Esc|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|  `|
+ * |-----------------------------------------------------------|
+ * |Tab  |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]| BS  |
+ * |-----------------------------------------------------------|
+ * |Contro|  A|  S|  D|  F|  G|  H|  J|  K|  L|Fn3|  '|Return  |
+ * |-----------------------------------------------------------|
+ * |Shift   |  Z|  X|  C|  V|  B|  N|  M|  ,|  .|Fn2|Shift     |
+ * |-----------------------------------------------------------|
+ * |Ctrl |   |Alt  |           Fn4             |Alt  |   |Fn1  |
+ * `-----'   `---------------------------------------'   `-----'
+ *
+ * Matrix: 12x8
+ *    |       0 |       1 |       2 |       3 |       4 |       5 |       6 |       7
+ * ---+---------+---------+---------+---------+---------+---------+---------+---------
+ *  0 |         |         | LCTRL   |         |         |         | RCTRL   |        
+ *  1 |         | LSHIFT  |         |         |         |         | RSHIFT  |        
+ *  2 |         | Tab     | Grave   | 1       | Q       | A       | Z       |        
+ *  3 |         | Cpslck  |         | 2       | W       | S       | X       |        
+ *  4 |         |         |         | 3       | E       | D       | C       |        
+ *  5 | G       | T       | 5       | 4       | R       | F       | V       | B      
+ *  6 |         | Bckspc  |         |         | Key*1   | Bckslsh | Enter   | Space  
+ *  7 | H       | Y       | 6       | 7       | U       | J       | M       | N      
+ *  8 |         | Rbrckt  | Equal   | 8       | I       | K       | Comma   |
+ *  9 |         |         |         | 9       | O       | L       | Dot     |        
+ *  A |         | Lbrckt  | Minus   | 0       | P       | Smcolon |         | Slash  
+ *  B | LALT    |         |         |         |         |         |         | RALT   
+ *  Key*1 This key locates between Equal and Backspace.
+ *
+ *  Original matrix here: http://geekhack.org/showthread.php?7767-Wireless-Model-M&p=133911&viewfull=1#post133911
+ */
+#define KEYMAP( \
+    K22, K23, K33, K43, K53, K52, K72, K73, K83, K93, KA3, KA2, K82, K64, K61, \
+    K21, K24, K34, K44, K54, K51, K71, K74, K84, K94, KA4, KA1, K81, K65, \
+    K31, K25, K35, K45, K55, K50, K70, K75, K85, K95, KA5, KA0, K66, \
+    K11, K26, K36, K46, K56, K57, K77, K76, K86, K96, KA7, K16, \
+    K02, KB0,      K67,      KB7, K06 \
+) { \
+    { KB_NO,    KB_NO,    KB_##K02, KB_NO,    KB_NO,    KB_NO,    KB_##K06, KB_NO    }, \
+    { KB_NO,    KB_##K11, KB_NO,    KB_NO,    KB_NO,    KB_NO,    KB_##K16, KB_NO    }, \
+    { KB_NO,    KB_##K21, KB_##K22, KB_##K23, KB_##K24, KB_##K25, KB_##K26, KB_NO    }, \
+    { KB_NO,    KB_##K31, KB_NO,    KB_##K33, KB_##K34, KB_##K35, KB_##K36, KB_NO    }, \
+    { KB_NO,    KB_NO,    KB_NO,    KB_##K43, KB_##K44, KB_##K45, KB_##K46, KB_NO    }, \
+    { KB_##K50, KB_##K51, KB_##K52, KB_##K53, KB_##K54, KB_##K55, KB_##K56, KB_##K57 }, \
+    { KB_NO,    KB_##K61, KB_NO,    KB_NO,    KB_##K64, KB_##K65, KB_##K66, KB_##K67 }, \
+    { KB_##K70, KB_##K71, KB_##K72, KB_##K73, KB_##K74, KB_##K75, KB_##K76, KB_##K77 }, \
+    { KB_NO,    KB_##K81, KB_##K82, KB_##K83, KB_##K84, KB_##K85, KB_##K86, KB_NO    }, \
+    { KB_NO,    KB_NO,    KB_NO,    KB_##K93, KB_##K94, KB_##K95, KB_##K96, KB_NO    }, \
+    { KB_##KA0, KB_##KA1, KB_##KA2, KB_##KA3, KB_##KA4, KB_##KA5, KB_NO,    KB_##KA7 }, \
+    { KB_##KB0, KB_NO,    KB_NO,    KB_NO,    KB_NO,    KB_NO,    KB_NO,    KB_##KB7 }, \
+}
+
+#define KEYCODE(layer, row, col) (pgm_read_byte(&keymaps[(layer)][(row)][(col)]))
+
+
+// Assign Fn key(0-7) to a layer to which switch with the Fn key pressed.
+static const uint8_t PROGMEM fn_layer[] = {
+    0,              // Fn0
+    1,              // Fn1
+    2,              // Fn2
+    3,              // Fn3
+    4,              // Fn4
+    0,              // Fn5
+    0,              // Fn6
+    0               // Fn7
+};
+
+// Assign Fn key(0-7) to a keycode sent when release Fn key without use of the layer.
+// See layer.c for details.
+static const uint8_t PROGMEM fn_keycode[] = {
+    KB_NO,          // Fn0
+    KB_NO,          // Fn1
+    KB_SLSH,        // Fn2
+    KB_SCLN,        // Fn3
+    KB_SPC,         // Fn4
+    KB_NO,          // Fn5
+    KB_NO,          // Fn6
+    KB_NO           // Fn7
+};
+
+static const uint8_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+    /* Layer 0: Default Layer
+     * ,-----------------------------------------------------------.
+     * |Esc|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|  `|
+     * |-----------------------------------------------------------|
+     * |Tab  |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]| BS  |
+     * |-----------------------------------------------------------|
+     * |Contro|  A|  S|  D|  F|  G|  H|  J|  K|  L|Fn3|  '|Return  |
+     * |-----------------------------------------------------------|
+     * |Shift   |  Z|  X|  C|  V|  B|  N|  M|  ,|  .|Fn2|Shift     |
+     * |-----------------------------------------------------------|
+     * |Ctrl |   |Alt  |           Fn4             |Alt  |   |Fn1  |
+     * `-----'   `---------------------------------------'   `-----'
+     */
+    KEYMAP(ESC, 1,   2,   3,   4,   5,   6,   7,   8,   9,   0,   MINS,EQL, BSLS,GRV, \
+           TAB, Q,   W,   E,   R,   T,   Y,   U,   I,   O,   P,   LBRC,RBRC,BSPC, \
+           LCTL,A,   S,   D,   F,   G,   H,   J,   K,   L,   FN3, QUOT,ENT, \
+           LSFT,Z,   X,   C,   V,   B,   N,   M,   COMM,DOT, FN2, FN1, \
+           LGUI,     LALT,          FN4,           RALT,     FN1),
+
+
+    /* Layer 1: HHKB mode (HHKB Fn)
+     * ,-----------------------------------------------------------.
+     * |Esc| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|Ins|Del|
+     * |-----------------------------------------------------------|
+     * |Caps |   |   |   |   |   |   |   |Psc|Slk|Pus|Up |   |     |
+     * |-----------------------------------------------------------|
+     * |Contro|VoD|VoU|Mut|   |   |  *|  /|Hom|PgU|Lef|Rig|        |
+     * |-----------------------------------------------------------|
+     * |Shift   |   |   |   |   |   |  +|  -|End|PgD|Dow|Shift     |
+     * |-----------------------------------------------------------|
+     * |Ctrl |   |Alt  |           Space           |Alt  |   |Fn1  |
+     * `-----'   `---------------------------------------'   `-----'
+     */ 
+    KEYMAP(ESC, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, INS, DEL, \
+           CAPS,NO,  NO,  NO,  NO,  NO,  NO,  NO,  PSCR,SLCK,BRK, UP,  NO,  NO, \
+           LCTL,VOLD,VOLU,MUTE,NO,  NO,  PAST,PSLS,HOME,PGUP,LEFT,RGHT,NO, \
+           LSFT,NO,  NO,  NO,  NO,  NO,  PPLS,PMNS,END, PGDN,DOWN,FN1, \
+           LGUI,     LALT,          SPC,           RALT,     FN1),
+
+
+    /* Layer 2: Vi mode (Quote/Rmeta)
+     * ,-----------------------------------------------------------.
+     * |  `| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|   |   |
+     * |-----------------------------------------------------------|
+     * |  \  |Hom|PgD|Up |PgU|End|Hom|PgD|PgU|End|   |   |   |     |
+     * |-----------------------------------------------------------|
+     * |Contro|   |Lef|Dow|Rig|   |Lef|Dow|Up |Rig|   |   |        |
+     * |-----------------------------------------------------------|
+     * |Shift   |   |   |   |   |   |Hom|PgD|PgU|End|xxx|Shift     |
+     * |-----------------------------------------------------------|
+     * |Ctrl |   |Alt  |           Space           |Alt  |   |Fn1  |
+     * `-----'   `---------------------------------------'   `-----'
+     */
+    KEYMAP(GRV, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, NO,  NO, \
+           BSLS,HOME,PGDN,UP,  PGUP,END, HOME,PGDN,PGUP,END, NO,  NO,  NO,  NO, \
+           LCTL,NO,  LEFT,DOWN,RGHT,NO,  LEFT,DOWN,UP,  RGHT,NO,  NO,  NO, \
+           LSFT,NO,  NO,  NO,  NO,  NO,  HOME,PGDN,PGUP,END, FN2, RSFT, \
+           LGUI,     LALT,          SPC,           RALT,     NO),
+
+
+
+    /* Layer 3: Mouse mode (Semicolon)
+     * ,-----------------------------------------------------------.
+     * |  `| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|   |   |
+     * |-----------------------------------------------------------|
+     * |  \  |MwL|MwD|McU|MwU|MwR|MwL|MwD|MwU|MwR|   |   |   |     |
+     * |-----------------------------------------------------------|
+     * |Contro|   |McL|McD|McR|   |McL|McD|McU|McR|xxx|   |        |
+     * |-----------------------------------------------------------|
+     * |Shift   |   |   |Mb1|Mb2|Mb3|Mb2|Mb1|   |   |   |Shift     |
+     * |-----------------------------------------------------------|
+     * |Ctrl |   |Alt  |           Space           |Alt  |   |     |
+     * `-----'   `---------------------------------------'   `-----'
+     * Mc: Mouse Cursor / Mb: Mouse Button / Mw: Mouse Wheel 
+     */
+    KEYMAP(GRV, F1,  F2,  F3,  F4,  F5,  F6,  F7,  F8,  F9,  F10, F11, F12, NO, NO, \
+           BSLS,WH_L,WH_D,MS_U,WH_U,WH_R,WH_L,WH_D,WH_U,WH_R,NO,  NO,  NO,  NO, \
+           LCTL,NO,  MS_L,MS_D,MS_R,NO,  MS_L,MS_D,MS_U,MS_R,FN3, NO,  NO, \
+           LSFT,NO,  NO,  BTN1,BTN2,BTN3,BTN2,BTN1,NO,  NO,  NO,  RSFT, \
+           LGUI,     LALT,          BTN1,          RALT,     NO),
+
+
+    /* Layer 4: Matias half keyboard style (Space)
+     * ,-----------------------------------------------------------.
+     * |Esc| F1| F2| F3| F4| F5| F6| F7| F8| F9|F10|F11|F12|Delete |
+     * |-----------------------------------------------------------|
+     * |Backs|  P|  O|  I|  U|  Y|  T|  R|  E|  W|  Q|   |   |Tab  |
+     * |-----------------------------------------------------------|
+     * |Contro|  ;|  L|  K|  J|  H|  G|  F|  D|  S|  A|Con|Control |
+     * |-----------------------------------------------------------|
+     * |Shift   |  /|  .|  ,|  M|  N|  B|  V|  C|  X|  Z|Shift     |
+     * |-----------------------------------------------------------|
+     * |Ctrl |   |Alt  |           Fn4             |Alt  |   |     |
+     * `-----'   `---------------------------------------'   `-----'
+     */
+    KEYMAP(MINS,0,   9,   8,   7,   6,   5,   4,   3,   2,   1,   NO,  NO,  NO, ESC, \
+           BSPC,P,   O,   I,   U,   Y,   T,   R,   E,   W,   Q,   NO,  NO,  TAB, \
+           LCTL,SCLN,L,   K,   J,   H,   G,   F,   D,   S,   A,   RCTL,RCTL, \
+           LSFT,SLSH,DOT, COMM,M,   N,   B,   V,   C,   X,   Z,   RSFT, \
+           LGUI,     LALT,          FN4,           RALT,     NO),
+
+};
+
+
+uint8_t keymap_get_keycode(uint8_t layer, uint8_t row, uint8_t col)
+{
+    return KEYCODE(layer, row, col);
+}
+
+uint8_t keymap_fn_layer(uint8_t fn_bits)
+{
+    return pgm_read_byte(&fn_layer[biton(fn_bits)]);
+}
+
+uint8_t keymap_fn_keycode(uint8_t fn_bits)
+{
+    return pgm_read_byte(&fn_keycode[(biton(fn_bits))]);
+}
diff --git a/hbk/led.c b/hbk/led.c
new file mode 100644
index 00000000..fc0eeb0f
--- /dev/null
+++ b/hbk/led.c
@@ -0,0 +1,24 @@
+/*
+Copyright 2012 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/>.
+*/
+
+#include "stdint.h"
+#include "led.h"
+
+
+void led_set(uint8_t usb_led)
+{
+}
diff --git a/hbk/matrix.c b/hbk/matrix.c
new file mode 100644
index 00000000..d7c06636
--- /dev/null
+++ b/hbk/matrix.c
@@ -0,0 +1,270 @@
+/*
+Copyright 2012 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/>.
+*/
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <avr/io.h>
+#include <util/delay.h>
+#include "print.h"
+#include "debug.h"
+#include "util.h"
+#include "matrix.h"
+
+
+/*
+ * Happy Buckling Keyboard(IBM Model M mod)
+ *
+ * Pin usage:
+ *   COL: PD0-7
+ *   ROW: PB0-7, PF4-7
+ */
+
+#if (MATRIX_COLS > 16)
+#   error "MATRIX_COLS must not exceed 16"
+#endif
+#if (MATRIX_ROWS > 255)
+#   error "MATRIX_ROWS must not exceed 255"
+#endif
+
+
+#ifndef DEBOUNCE
+#   define DEBOUNCE	0
+#endif
+static uint8_t debouncing = DEBOUNCE;
+
+// matrix state buffer(1:on, 0:off)
+#if (MATRIX_COLS <= 8)
+static uint8_t *matrix;
+static uint8_t *matrix_prev;
+static uint8_t _matrix0[MATRIX_ROWS];
+static uint8_t _matrix1[MATRIX_ROWS];
+#else
+static uint16_t *matrix;
+static uint16_t *matrix_prev;
+static uint16_t _matrix0[MATRIX_ROWS];
+static uint16_t _matrix1[MATRIX_ROWS];
+#endif
+
+#ifdef MATRIX_HAS_GHOST
+static bool matrix_has_ghost_in_row(uint8_t row);
+#endif
+static uint8_t read_col(void);
+static void unselect_rows(void);
+static void select_row(uint8_t row);
+
+
+inline
+uint8_t matrix_rows(void)
+{
+    return MATRIX_ROWS;
+}
+
+inline
+uint8_t matrix_cols(void)
+{
+    return MATRIX_COLS;
+}
+
+void matrix_init(void)
+{
+    print_enable = true;
+    debug_enable = true;
+    debug_matrix = true;
+    debug_keyboard = false;
+    debug_mouse = false;
+    print("debug enabled.\n");
+
+    // JTAG disable for PORT F. write JTD bit twice within four cycles.
+    MCUCR |= (1<<JTD);
+    MCUCR |= (1<<JTD);
+
+    // initialize rows
+    unselect_rows();
+
+    // initialize columns to input with pull-up(DDR:0, PORT:1)
+    DDRD = 0x00;
+    PORTD = 0xFF;
+
+    // initialize matrix state: all keys off
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix0[i] = 0x00;
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) _matrix1[i] = 0x00;
+    matrix = _matrix0;
+    matrix_prev = _matrix1;
+}
+
+uint8_t matrix_scan(void)
+{
+    if (!debouncing) {
+        uint8_t *tmp = matrix_prev;
+        matrix_prev = matrix;
+        matrix = tmp;
+    }
+
+    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+        unselect_rows();
+        select_row(i);
+        _delay_us(30);  // without this wait read unstable value.
+        if (matrix[i] != (uint8_t)~read_col()) {
+            matrix[i] = (uint8_t)~read_col();
+            if (debouncing) {
+                debug("bounce!: "); debug_hex(debouncing); print("\n");
+            }
+            _delay_ms(1);   // TODO: work around. HAHAHAHAHAAHA
+            debouncing = DEBOUNCE;
+        }
+    }
+    unselect_rows();
+
+    if (debouncing) {
+        debouncing--;
+    }
+
+    return 1;
+}
+
+bool matrix_is_modified(void)
+{
+    if (debouncing) return false;
+    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+        if (matrix[i] != matrix_prev[i]) {
+            return true;
+        }
+    }
+    return false;
+}
+
+inline
+bool matrix_has_ghost(void)
+{
+#ifdef MATRIX_HAS_GHOST
+    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+        if (matrix_has_ghost_in_row(i))
+            return true;
+    }
+#endif
+    return false;
+}
+
+inline
+bool matrix_is_on(uint8_t row, uint8_t col)
+{
+    return (matrix[row] & (1<<col));
+}
+
+inline
+#if (MATRIX_COLS <= 8)
+uint8_t matrix_get_row(uint8_t row)
+#else
+uint16_t matrix_get_row(uint8_t row)
+#endif
+{
+    return matrix[row];
+}
+
+void matrix_print(void)
+{
+    print("\nr/c 01234567\n");
+    for (uint8_t row = 0; row < matrix_rows(); row++) {
+        phex(row); print(": ");
+#if (MATRIX_COLS <= 8)
+        pbin_reverse(matrix_get_row(row));
+#else
+        pbin_reverse16(matrix_get_row(row));
+#endif
+#ifdef MATRIX_HAS_GHOST
+        if (matrix_has_ghost_in_row(row)) {
+            print(" <ghost");
+        }
+#endif
+        print("\n");
+    }
+}
+
+uint8_t matrix_key_count(void)
+{
+    uint8_t count = 0;
+    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+#if (MATRIX_COLS <= 8)
+        count += bitpop(matrix[i]);
+#else
+        count += bitpop16(matrix[i]);
+#endif
+    }
+    return count;
+}
+
+#ifdef MATRIX_HAS_GHOST
+inline
+static bool matrix_has_ghost_in_row(uint8_t row)
+{
+    // no ghost exists in case less than 2 keys on
+    if (((matrix[row] - 1) & matrix[row]) == 0)
+        return false;
+
+    // ghost exists in case same state as other row
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
+        if (i != row && (matrix[i] & matrix[row]) == matrix[row])
+            return true;
+    }
+    return false;
+}
+#endif
+
+inline
+static uint8_t read_col(void)
+{
+    return PIND;
+}
+
+inline
+static void unselect_rows(void)
+{
+    // Hi-Z(DDR:0, PORT:0) to unselect
+    DDRB  &= ~0b11111111;
+    PORTB &= ~0b11111111;
+    DDRF  &= ~0b11110000;
+    PORTF &= ~0b11110000;
+}
+
+inline
+static void select_row(uint8_t row)
+{
+    // Output low(DDR:1, PORT:0) to select
+    switch (row) {
+        case 0:
+        case 1:
+        case 2:
+        case 3:
+        case 4:
+        case 5:
+        case 6:
+        case 7:
+            DDRB  |=  (1<<row);
+            PORTB &= ~(1<<row);
+            break;
+        case 8:
+            DDRF  |=  (1<<4);
+            PORTF &= ~(1<<4);
+            break;
+        case 9:
+        case 10:
+        case 11:
+            DDRF  |=  (1<<(row-4));
+            PORTF &= ~(1<<(row-4));
+            break;
+    }
+}