21 files changed, 824 insertions, 6 deletions

diff --git a/doc/keymap.md b/doc/keymap.md
index d1985e567..6f2a663fc 100644
--- a/doc/keymap.md
+++ b/doc/keymap.md
@@ -455,6 +455,35 @@ Turn the backlight on and off without changing level.
 
 
 
+### 2.6 Swap-Hands Action
+The swap-hands action allows support for one-handed keyboards without requiring a separate layer. Set `ONEHAND_ENABLE` in the Makefile and define a `hand_swap_config` entry in your keymap. Now whenever the `ACTION_SWAP_HANDS` command key is pressed the keyboard is mirrored. For instance, to type "Hello, World" on QWERTY you would type `^Ge^s^s^w^c W^wr^sd`
+
+### 2.6.1 Configuration
+The configuration table is a simple 2-dimensional array to map from column/row to new column/row. Example `hand_swap_config` for Planck:
+
+```
+const keypos_t hand_swap_config[MATRIX_ROWS][MATRIX_COLS] = {
+  {{11, 0}, {10, 0}, {9, 0}, {8, 0}, {7, 0}, {6, 0}, {5, 0}, {4, 0}, {3, 0}, {2, 0}, {1, 0}, {0, 0}},
+  {{11, 1}, {10, 1}, {9, 1}, {8, 1}, {7, 1}, {6, 1}, {5, 1}, {4, 1}, {3, 1}, {2, 1}, {1, 1}, {0, 1}},
+  {{11, 2}, {10, 2}, {9, 2}, {8, 2}, {7, 2}, {6, 2}, {5, 2}, {4, 2}, {3, 2}, {2, 2}, {1, 2}, {0, 2}},
+  {{11, 3}, {10, 3}, {9, 3}, {8, 3}, {7, 3}, {6, 3}, {5, 3}, {4, 3}, {3, 3}, {2, 3}, {1, 3}, {0, 3}},
+};
+```
+
+Note that the array indices are reversed same as the matrix and the values are of type `keypos_t` which is `{col, row}` and all values are zero-based. In the example above, `hand_swap_config[2][4]` (third row, fifth column) would return {7, 2} (third row, eighth column).
+
+### 2.6.2 Advanced Swap Commands
+- **`ACTION_SWAP_HANDS()`** Swaps hands when pressed, returns to normal when released (momentary).
+- **`ACTION_SWAP_HANDS_TOGGLE()`** Toggles swap on and off with every keypress.
+- **`ACTION_SWAP_HANDS_TAP_TOGGLE()`** Toggles with a tap; momentary when held.
+- **`ACTION_SWAP_HANDS_TAP_KEY(key)`** Sends `key` with a tap; momentary swap when held.
+- **`ACTION_SWAP_HANDS_ON_OFF()`** Alias for `ACTION_SWAP_HANDS()`
+- **`ACTION_SWAP_HANDS_OFF_ON()`** Momentarily turns off swap.
+- **`ACTION_SWAP_HANDS_ON()`** Turns on swapping and leaves it on.
+- **`ACTION_SWAP_HANDS_OFF()`** Turn off swapping and leaves it off. Good for returning to a known state.
+
+
+
 ## 3. Layer switching Example
 There are some ways to switch layer with 'Layer' actions.
 
diff --git a/keyboards/ergodox/infinity/infinity.c b/keyboards/ergodox/infinity/infinity.c
index f89e046d0..c5793385f 100644
--- a/keyboards/ergodox/infinity/infinity.c
+++ b/keyboards/ergodox/infinity/infinity.c
@@ -130,3 +130,27 @@ void ergodox_right_led_3_off(void){
 
 void ergodox_right_led_off(uint8_t led){
 }
+
+#ifdef ONEHAND_ENABLE
+__attribute__ ((weak))
+const keypos_t hand_swap_config[MATRIX_ROWS][MATRIX_COLS] = {
+    {{0, 9}, {1, 9}, {2, 9}, {3, 9}, {4, 9}},
+    {{0, 10}, {1, 10}, {2, 10}, {3, 10}, {4, 10}},
+    {{0, 11}, {1, 11}, {2, 11}, {3, 11}, {4, 11}},
+    {{0, 12}, {1, 12}, {2, 12}, {3, 12}, {4, 12}},
+    {{0, 13}, {1, 13}, {2, 13}, {3, 13}, {4, 13}},
+    {{0, 14}, {1, 14}, {2, 14}, {3, 14}, {4, 14}},
+    {{0, 15}, {1, 15}, {2, 15}, {3, 15}, {4, 15}},
+    {{0, 16}, {1, 16}, {2, 16}, {3, 16}, {4, 16}},
+    {{0, 17}, {1, 17}, {2, 17}, {3, 17}, {4, 17}},
+    {{0, 0}, {1, 0}, {2, 0}, {3, 0}, {4, 0}},
+    {{0, 1}, {1, 1}, {2, 1}, {3, 1}, {4, 1}},
+    {{0, 2}, {1, 2}, {2, 2}, {3, 2}, {4, 2}},
+    {{0, 3}, {1, 3}, {2, 3}, {3, 3}, {4, 3}},
+    {{0, 4}, {1, 4}, {2, 4}, {3, 4}, {4, 4}},
+    {{0, 5}, {1, 5}, {2, 5}, {3, 5}, {4, 5}},
+    {{0, 6}, {1, 6}, {2, 6}, {3, 6}, {4, 6}},
+    {{0, 7}, {1, 7}, {2, 7}, {3, 7}, {4, 7}},
+    {{0, 8}, {1, 8}, {2, 8}, {3, 8}, {4, 8}},
+};
+#endif
diff --git a/keyboards/kitten_paw/Makefile b/keyboards/kitten_paw/Makefile
new file mode 100644
index 000000000..912292173
--- /dev/null
+++ b/keyboards/kitten_paw/Makefile
@@ -0,0 +1,77 @@
+
+
+# MCU name
+#MCU = at90usb1287
+MCU = atmega32u2
+
+# Processor frequency.
+#     This will define a symbol, F_CPU, in all source code files equal to the
+#     processor frequency in Hz. You can then use this symbol in your source code to
+#     calculate timings. Do NOT tack on a 'UL' at the end, this will be done
+#     automatically to create a 32-bit value in your source code.
+#
+#     This will be an integer division of F_USB below, as it is sourced by
+#     F_USB after it has run through any CPU prescalers. Note that this value
+#     does not *change* the processor frequency - it should merely be updated to
+#     reflect the processor speed set externally so that the code can use accurate
+#     software delays.
+F_CPU = 16000000
+
+
+#
+# LUFA specific
+#
+# Target architecture (see library "Board Types" documentation).
+ARCH = AVR8
+
+# Input clock frequency.
+#     This will define a symbol, F_USB, in all source code files equal to the
+#     input clock frequency (before any prescaling is performed) in Hz. This value may
+#     differ from F_CPU if prescaling is used on the latter, and is required as the
+#     raw input clock is fed directly to the PLL sections of the AVR for high speed
+#     clock generation for the USB and other AVR subsections. Do NOT tack on a 'UL'
+#     at the end, this will be done automatically to create a 32-bit value in your
+#     source code.
+#
+#     If no clock division is performed on the input clock inside the AVR (via the
+#     CPU clock adjust registers or the clock division fuses), this will be equal to F_CPU.
+F_USB = $(F_CPU)
+
+# Interrupt driven control endpoint task(+60)
+OPT_DEFS += -DINTERRUPT_CONTROL_ENDPOINT
+
+
+# Boot Section Size in *bytes*
+#   Teensy halfKay   512
+#   Teensy++ halfKay 1024
+#   Atmel DFU loader 4096
+#   LUFA bootloader  4096
+#   USBaspLoader     2048
+        OPT_DEFS += -DBOOTLOADER_SIZE=4096
+
+
+# Build Options
+#   change yes to no to disable
+#
+BOOTMAGIC_ENABLE ?= no      # Virtual DIP switch configuration(+1000)
+MOUSEKEY_ENABLE ?= yes       # Mouse keys(+4700)
+EXTRAKEY_ENABLE ?= yes       # Audio control and System control(+450)
+CONSOLE_ENABLE ?= yes        # Console for debug(+400)
+COMMAND_ENABLE ?= yes        # Commands for debug and configuration
+# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE ?= no       # Breathing sleep LED during USB suspend
+# if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
+NKRO_ENABLE ?= no            # USB Nkey Rollover
+BACKLIGHT_ENABLE ?= no       # Enable keyboard backlight functionality on B7 by default
+MIDI_ENABLE ?= no            # MIDI controls
+UNICODE_ENABLE ?= no         # Unicode
+BLUETOOTH_ENABLE ?= no       # Enable Bluetooth with the Adafruit EZ-Key HID
+AUDIO_ENABLE ?= no           # Audio output on port C6
+
+CUSTOM_MATRIX = yes
+SRC += matrix.c led.c
+
+ifndef QUANTUM_DIR
+        include ../../Makefile
+endif
+
diff --git a/keyboards/kitten_paw/config.h b/keyboards/kitten_paw/config.h
new file mode 100644
index 000000000..d7089734a
--- /dev/null
+++ b/keyboards/kitten_paw/config.h
@@ -0,0 +1,162 @@
+/*
+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
+
+#include "config_common.h"
+
+
+/* USB Device descriptor parameter */
+#define VENDOR_ID       0xFEED
+#define PRODUCT_ID      0x6050
+#define DEVICE_VER      0x0104
+#define MANUFACTURER    Costar
+#define PRODUCT         Majestouch
+
+/* key matrix size */
+#define MATRIX_ROWS 8
+#define MATRIX_COLS 18
+
+/*
+ * Keyboard Matrix Assignments
+ *
+ * Change this to how you wired your keyboard
+ * COLS: AVR pins used for columns, left to right
+ * ROWS: AVR pins used for rows, top to bottom
+ * DIODE_DIRECTION: COL2ROW = COL = Anode (+), ROW = Cathode (-, marked on diode)
+ *                  ROW2COL = ROW = Anode (+), COL = Cathode (-, marked on diode)
+ *
+*/
+//#define MATRIX_ROW_PINS { D0, D5 }
+//#define MATRIX_COL_PINS { F1, F0, B0 }
+//#define UNUSED_PINS
+
+/* COL2ROW or ROW2COL */
+#define DIODE_DIRECTION COL2ROW
+ 
+// #define BACKLIGHT_PIN B7
+// #define BACKLIGHT_BREATHING
+// #define BACKLIGHT_LEVELS 3
+
+
+/* Debounce reduces chatter (unintended double-presses) - set 0 if debouncing is not needed */
+#define DEBOUNCING_DELAY 5
+
+/* define if matrix has ghost (lacks anti-ghosting diodes) */
+//#define MATRIX_HAS_GHOST
+
+/* number of backlight levels */
+
+/* Mechanical locking support. Use KC_LCAP, KC_LNUM or KC_LSCR instead in keymap */
+#define LOCKING_SUPPORT_ENABLE
+/* Locking resynchronize hack */
+#define LOCKING_RESYNC_ENABLE
+
+/*
+ * Force NKRO
+ *
+ * Force NKRO (nKey Rollover) to be enabled by default, regardless of the saved
+ * state in the bootmagic EEPROM settings. (Note that NKRO must be enabled in the
+ * makefile for this to work.)
+ *
+ * If forced on, NKRO can be disabled via magic key (default = LShift+RShift+N)
+ * until the next keyboard reset.
+ *
+ * NKRO may prevent your keystrokes from being detected in the BIOS, but it is
+ * fully operational during normal computer usage.
+ *
+ * For a less heavy-handed approach, enable NKRO via magic key (LShift+RShift+N)
+ * or via bootmagic (hold SPACE+N while plugging in the keyboard). Once set by
+ * bootmagic, NKRO mode will always be enabled until it is toggled again during a
+ * power-up.
+ *
+ */
+//#define FORCE_NKRO
+
+/*
+ * Magic Key Options
+ *
+ * Magic keys are hotkey commands that allow control over firmware functions of
+ * the keyboard. They are best used in combination with the HID Listen program,
+ * found here: https://www.pjrc.com/teensy/hid_listen.html
+ *
+ * The options below allow the magic key functionality to be changed. This is
+ * useful if your keyboard/keypad is missing keys and you want magic key support.
+ *
+ */
+
+/* key combination for magic key command */
+#define IS_COMMAND() ( \
+    keyboard_report->mods == (MOD_BIT(KC_LSHIFT) | MOD_BIT(KC_RSHIFT)) \
+)
+
+/* control how magic key switches layers */
+//#define MAGIC_KEY_SWITCH_LAYER_WITH_FKEYS  true
+//#define MAGIC_KEY_SWITCH_LAYER_WITH_NKEYS  true
+//#define MAGIC_KEY_SWITCH_LAYER_WITH_CUSTOM false
+
+/* override magic key keymap */
+//#define MAGIC_KEY_SWITCH_LAYER_WITH_FKEYS
+//#define MAGIC_KEY_SWITCH_LAYER_WITH_NKEYS
+//#define MAGIC_KEY_SWITCH_LAYER_WITH_CUSTOM
+//#define MAGIC_KEY_HELP1          H
+//#define MAGIC_KEY_HELP2          SLASH
+//#define MAGIC_KEY_DEBUG          D
+//#define MAGIC_KEY_DEBUG_MATRIX   X
+//#define MAGIC_KEY_DEBUG_KBD      K
+//#define MAGIC_KEY_DEBUG_MOUSE    M
+//#define MAGIC_KEY_VERSION        V
+//#define MAGIC_KEY_STATUS         S
+//#define MAGIC_KEY_CONSOLE        C
+//#define MAGIC_KEY_LAYER0_ALT1    ESC
+//#define MAGIC_KEY_LAYER0_ALT2    GRAVE
+//#define MAGIC_KEY_LAYER0         0
+//#define MAGIC_KEY_LAYER1         1
+//#define MAGIC_KEY_LAYER2         2
+//#define MAGIC_KEY_LAYER3         3
+//#define MAGIC_KEY_LAYER4         4
+//#define MAGIC_KEY_LAYER5         5
+//#define MAGIC_KEY_LAYER6         6
+//#define MAGIC_KEY_LAYER7         7
+//#define MAGIC_KEY_LAYER8         8
+//#define MAGIC_KEY_LAYER9         9
+//#define MAGIC_KEY_BOOTLOADER     PAUSE
+//#define MAGIC_KEY_LOCK           CAPS
+//#define MAGIC_KEY_EEPROM         E
+//#define MAGIC_KEY_NKRO           N
+//#define MAGIC_KEY_SLEEP_LED      Z
+
+/*
+ * Feature disable options
+ *  These options are also useful to firmware size reduction.
+ */
+
+/* disable debug print */
+//#define NO_DEBUG
+
+/* disable print */
+//#define NO_PRINT
+
+/* disable action features */
+//#define NO_ACTION_LAYER
+//#define NO_ACTION_TAPPING
+//#define NO_ACTION_ONESHOT
+//#define NO_ACTION_MACRO
+//#define NO_ACTION_FUNCTION
+
+#endif
diff --git a/keyboards/kitten_paw/keymaps/default/keymap.c b/keyboards/kitten_paw/keymaps/default/keymap.c
new file mode 100644
index 000000000..f67235745
--- /dev/null
+++ b/keyboards/kitten_paw/keymaps/default/keymap.c
@@ -0,0 +1,51 @@
+#include "kitten_paw.h"
+
+enum layers {
+    DEFAULT,
+};
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+  [DEFAULT] = KEYMAP(\
+       KC_ESC,  KC_F1,  KC_F2,  KC_F3,  KC_F4,  KC_F5,  KC_F6,  KC_F7,  KC_F8,  KC_F9, KC_F10, KC_F11, KC_F12,          KC_PSCR,KC_SLCK,KC_PAUS,                        \
+       KC_GRV,   KC_1,   KC_2,   KC_3,   KC_4,   KC_5,   KC_6,   KC_7,   KC_8,   KC_9,   KC_0,KC_MINS, KC_EQL,KC_BSPC,   KC_INS,KC_HOME,KC_PGUP,  KC_NLCK,KC_PSLS,KC_PAST,KC_PMNS, \
+       KC_TAB,   KC_Q,   KC_W,   KC_E,   KC_R,   KC_T,   KC_Y,   KC_U,   KC_I,   KC_O,   KC_P,KC_LBRC,KC_RBRC,KC_BSLS,   KC_DEL, KC_END,KC_PGDN,    KC_P7,  KC_P8,  KC_P9,KC_PPLS, \
+      KC_CAPS,   KC_A,   KC_S,   KC_D,   KC_F,   KC_G,   KC_H,   KC_J,   KC_K,   KC_L,KC_SCLN,KC_QUOT,         KC_ENT,                              KC_P4,  KC_P5,  KC_P6,      \
+      KC_LSFT,KC_NUBS,   KC_Z,   KC_X,   KC_C,   KC_V,   KC_B,   KC_N,   KC_M,KC_COMM, KC_DOT,KC_SLSH,        KC_RSFT,            KC_UP,            KC_P1,  KC_P2,  KC_P3,KC_PENT, \
+      KC_LCTL,KC_LGUI,KC_LALT,                 KC_SPC,                                KC_RALT,KC_RGUI,KC_MENU,KC_RCTL,  KC_LEFT,KC_DOWN,KC_RGHT,    KC_P0,KC_PDOT)
+};
+
+const uint16_t PROGMEM fn_actions[] = {
+
+};
+
+const macro_t *action_get_macro(keyrecord_t *record, uint8_t id, uint8_t opt)
+{
+  // MACRODOWN only works in this function
+      switch(id) {
+        case 0:
+          if (record->event.pressed) {
+            register_code(KC_RSFT);
+          } else {
+            unregister_code(KC_RSFT);
+          }
+        break;
+      }
+    return MACRO_NONE;
+};
+
+
+void matrix_init_user(void) {
+
+}
+
+void matrix_scan_user(void) {
+
+}
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  return true;
+}
+
+void led_set_user(uint8_t usb_led) {
+
+}
\ No newline at end of file
diff --git a/keyboards/kitten_paw/kitten_paw.c b/keyboards/kitten_paw/kitten_paw.c
new file mode 100644
index 000000000..8713baf43
--- /dev/null
+++ b/keyboards/kitten_paw/kitten_paw.c
@@ -0,0 +1,30 @@
+#include "kitten_paw.h"
+
+void matrix_init_kb(void) {
+        // put your keyboard start-up code here
+        // runs once when the firmware starts up
+
+    matrix_init_quantum();
+        matrix_init_user();
+}
+
+void matrix_scan_kb(void) {
+        // put your looping keyboard code here
+        // runs every cycle (a lot)
+
+    matrix_scan_quantum();
+    matrix_scan_user();
+}
+
+bool process_record_kb(uint16_t keycode, keyrecord_t *record) {
+        // put your per-action keyboard code here
+        // runs for every action, just before processing by the firmware
+
+        return process_record_user(keycode, record);
+}
+
+void led_set_kb(uint8_t usb_led) {
+        // put your keyboard LED indicator (ex: Caps Lock LED) toggling code here
+
+        led_set_user(usb_led);
+}
diff --git a/keyboards/kitten_paw/kitten_paw.h b/keyboards/kitten_paw/kitten_paw.h
new file mode 100644
index 000000000..a6c1d27de
--- /dev/null
+++ b/keyboards/kitten_paw/kitten_paw.h
@@ -0,0 +1,47 @@
+#ifndef KITTEN_PAW_H
+#define KITTEN_PAW_H
+
+#include "quantum.h"
+
+// This a shortcut to help you visually see your layout.
+// The first section contains all of the arguements
+// The second converts the arguments into a two-dimensional array
+/*
+  Matrix col/row mapping
+  
+  ,----.    ,-------------------. ,-------------------. ,-------------------. ,--------------.
+  | J6 |    | I4 | H4 | H2 | H6 | | A7 | E6 | D2 | D4 | | B4 | B7 | B6 | B0 | | C7 | C5 | A5 |
+  `----'    `-------------------' `-------------------' `-------------------' `--------------'
+  ,-------------------------------------------------------------------------. ,--------------. ,-------------------.
+  | J4 | J7 | I7 | H7 | G7 | G4 | F4 | F7 | E7 | D7 | R7 | R4 | E4 |     B2 | | L4 | O4 | Q4 | | K1 | L1 | Q1 | Q0 |
+  |-------------------------------------------------------------------------| |--------------| |-------------------|
+  | J2   | J5 | I5 | H5 | G5 | G2 | F2 | F5 | E5 | D5 | R5 | R2 | E2 |   B3 | | K4 | O7 | Q7 | | K5 | L5 | Q5 | O5 |
+  |-------------------------------------------------------------------------| '--------------' |--------------     |
+  | O5    | J3 | I3 | H3 | G3 | G6 | F6 | F3 | E3 | D3 | R3 | R6 |       B1 |                  | K2 | L2 | Q2 |    |
+  |-------------------------------------------------------------------------|      ,----.      |-------------------|
+  | N2      | J1 | I1 | H1 | G1 | G0 | F0 | F1 | E1 | D1 | R0 |          N3 |      | O6 |      | K3 | L3 | Q3 | O3 |
+  |-------------------------------------------------------------------------| ,--------------. |--------------     |
+  | A4 | P2 | C6 |                  K6                  | C0 | M3 | D0 | A1 | | O0 | K0 | L0 | | L6      | Q6 |    |
+  `-------------------------------------------------------------------------' `--------------' `-------------------'
+*/
+
+#define KEYMAP( \
+  KJ6,      KI4, KH4, KH2, KH6, KA7, KE6, KD2, KD4, KB4, KB7, KB6, KB0,   KC7, KC5, KA5,                       \
+  KJ4, KJ7, KI7, KH7, KG7, KG4, KF4, KF7, KE7, KD7, KR7, KR4, KE4, KB2,   KL4, KO4, KQ4,   KK1, KL1, KQ1, KQ0, \
+  KJ2, KJ5, KI5, KH5, KG5, KG2, KF2, KF5, KE5, KD5, KR5, KR2, KE2, KB3,   KK4, KO7, KQ7,   KK5, KL5, KQ5, KO5, \
+  KI2, KJ3, KI3, KH3, KG3, KG6, KF6, KF3, KE3, KD3, KR3, KR6,      KB1,                    KK2, KL2, KQ2,      \
+  KN2, KI6, KJ1, KI1, KH1, KG1, KG0, KF0, KF1, KE1, KD1, KR0,      KN3,        KO6,        KK3, KL3, KQ3, KO3, \
+  KA4, KP2, KC6,                KK6,                KC0, KM3, KD0, KA1,   KO0, KK0, KL0,   KL6,      KQ6       \
+) \
+{ \
+    {KC_NO,  KB0,  KC0,  KD0,KC_NO,  KF0,  KG0,KC_NO,KC_NO,KC_NO,  KK0,  KL0,KC_NO,KC_NO,  KO0,KC_NO,  KQ0,  KR0}, \
+    {  KA1,  KB1,KC_NO,  KD1,  KE1,  KF1,  KG1,  KH1,  KI1,  KJ1,  KK1,  KL1,KC_NO,KC_NO,KC_NO,KC_NO,  KQ1,KC_NO}, \
+    {KC_NO,  KB2,KC_NO,  KD2,  KE2,  KF2,  KG2,  KH2,  KI2,  KJ2,  KK2,  KL2,KC_NO,  KN2,KC_NO,  KP2,  KQ2,  KR2}, \
+    {KC_NO,  KB3,KC_NO,  KD3,  KE3,  KF3,  KG3,  KH3,  KI3,  KJ3,  KK3,  KL3,  KM3,  KN3,  KO3,KC_NO,  KQ3,  KR3}, \
+    {  KA4,  KB4,KC_NO,  KD4,  KE4,  KF4,  KG4,  KH4,  KI4,  KJ4,  KK4,  KL4,KC_NO,KC_NO,  KO4,KC_NO,  KQ4,  KR4}, \
+    {  KA5,KC_NO,  KC5,  KD5,  KE5,  KF5,  KG5,  KH5,  KI5,  KJ5,  KK5,  KL5,KC_NO,KC_NO,  KO5,KC_NO,  KQ5,  KR5}, \
+    {KC_NO,  KB6,  KC6,KC_NO,  KE6,  KF6,  KG6,  KH6,  KI6,  KJ6,  KK6,  KL6,KC_NO,KC_NO,  KO6,KC_NO,  KQ6,  KR6}, \
+    {  KA7,  KB7,  KC7,  KD7,  KE7,  KF7,  KG7,  KH7,  KI7,  KJ7,KC_NO,KC_NO,KC_NO,KC_NO,  KO7,KC_NO,  KQ7,  KR7} \
+}
+
+#endif
diff --git a/keyboards/kitten_paw/led.c b/keyboards/kitten_paw/led.c
new file mode 100644
index 000000000..a1bf057c4
--- /dev/null
+++ b/keyboards/kitten_paw/led.c
@@ -0,0 +1,47 @@
+/*
+  Copyright 2014 Ralf Schmitt <ralf@bunkertor.net>
+
+  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 <avr/io.h>
+#include "stdint.h"
+#include "led.h"
+
+/* LED pin configuration
+ *
+ * Scroll Lock  PC5
+ * Caps Lock    PC6
+ * Num Lock     PB7
+ *
+ */
+void led_set(uint8_t usb_led) {
+  DDRB |= (1<<7);
+  DDRC |= (1<<5) | (1<<6);
+  
+  if (usb_led & (1<<USB_LED_CAPS_LOCK))
+    PORTC &= ~(1<<6);
+  else
+    PORTC |=  (1<<6);
+  
+  if (usb_led & (1<<USB_LED_NUM_LOCK))
+    PORTB &= ~(1<<7);
+  else
+    PORTB |=  (1<<7);
+  
+  if (usb_led & (1<<USB_LED_SCROLL_LOCK))
+    PORTC &= ~(1<<5);
+  else
+    PORTC |=  (1<<5);
+}
diff --git a/keyboards/kitten_paw/matrix.c b/keyboards/kitten_paw/matrix.c
new file mode 100644
index 000000000..46875293f
--- /dev/null
+++ b/keyboards/kitten_paw/matrix.c
@@ -0,0 +1,164 @@
+/*
+  Copyright 2014 Ralf Schmitt <ralf@bunkertor.net>
+
+  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"
+
+#ifndef DEBOUNCING_DELAY
+#   define DEBOUNCING_DELAY 5
+#endif
+static uint8_t debouncing = DEBOUNCING_DELAY;
+
+static matrix_row_t matrix[MATRIX_ROWS];
+static matrix_row_t matrix_debouncing[MATRIX_ROWS];
+
+static uint8_t read_rows(void);
+static void select_col(uint8_t col);
+
+inline uint8_t matrix_rows(void) {
+  return MATRIX_ROWS;
+}
+
+inline uint8_t matrix_cols(void) {
+  return MATRIX_COLS;
+}
+
+/* Column pin configuration
+ *
+ * col: 0    1    2    3    4    5    6    7
+ * pin: PC7  PD5  PD3  PD1  PC2  PD6  PD4  PD2
+ *
+ * Rrr pin configuration 
+ *
+ * These rrrs uses one 74HC154 4 to 16 bit demultiplexer (low
+ * active), together with 2 rrrs driven directly from the micro
+ * controller, to control the 18 rrrs. The rrrs are driven from
+ * pins B6,5,4,3,2,1,0.
+ */
+void matrix_init(void) {
+  DDRC  &= ~0b10000100;  // Row input pins
+  DDRD  &= ~0b01111110;
+  PORTC |=  0b10000100;
+  PORTD |=  0b01111110;
+
+  DDRB  |=  0b01111111;  // Column output pins
+
+  for (uint8_t i=0; i < MATRIX_ROWS; i++)  {
+    matrix[i] = 0;
+    matrix_debouncing[i] = 0;
+  }
+}
+
+uint8_t matrix_scan(void) {
+  for (uint8_t col = 0; col < MATRIX_COLS; col++) {
+    select_col(col);
+    _delay_us(3);
+    uint8_t rows = read_rows();
+    for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
+      bool prev_bit = matrix_debouncing[row] & ((matrix_row_t)1<<col);
+      bool curr_bit = rows & (1<<row);
+      if (prev_bit != curr_bit) {
+        matrix_debouncing[row] ^= ((matrix_row_t)1<<col);
+        debouncing = DEBOUNCING_DELAY;
+      }
+    }
+  }
+  
+  if (debouncing) {
+    if (--debouncing) {
+      _delay_ms(1);
+    }
+    else {
+      for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+        matrix[i] = matrix_debouncing[i];
+      }
+    }
+  }
+  
+  return 1;
+}
+
+bool matrix_is_modified(void) {
+  if (debouncing)
+    return false;
+  else
+    return true;
+}
+
+inline bool matrix_is_on(uint8_t row, uint8_t col) {
+  return (matrix[row] & ((matrix_row_t)1<<col));
+}
+
+inline matrix_row_t matrix_get_row(uint8_t row) {
+  return matrix[row];
+}
+
+void matrix_print(void) {
+  print("\nr/c 0123456789ABCDEF\n");
+  for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
+    xprintf("%02X: %032lb\n", row, bitrev32(matrix_get_row(row)));
+  }
+}
+
+uint8_t matrix_key_count(void) {
+  uint8_t count = 0;
+  for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+    count += bitpop32(matrix[i]);
+  }
+  return count;
+}
+
+static uint8_t read_rows(void) {
+  return
+    (PINC&(1<<7) ? 0 : (1<<0)) |
+    (PIND&(1<<5) ? 0 : (1<<1)) |
+    (PIND&(1<<3) ? 0 : (1<<2)) |
+    (PIND&(1<<1) ? 0 : (1<<3)) |
+    (PINC&(1<<2) ? 0 : (1<<4)) |
+    (PIND&(1<<2) ? 0 : (1<<5)) |
+    (PIND&(1<<4) ? 0 : (1<<6)) |
+    (PIND&(1<<6) ? 0 : (1<<7));
+}
+
+static void select_col(uint8_t col) {
+  switch (col) {
+  case  0: PORTB = (PORTB & ~0b01111111) | 0b01100100; break;
+  case  1: PORTB = (PORTB & ~0b01111111) | 0b01101100; break;
+  case  2: PORTB = (PORTB & ~0b01111111) | 0b01100010; break;
+  case  3: PORTB = (PORTB & ~0b01111111) | 0b01111010; break;
+  case  4: PORTB = (PORTB & ~0b01111111) | 0b01100110; break;
+  case  5: PORTB = (PORTB & ~0b01111111) | 0b01110110; break;
+  case  6: PORTB = (PORTB & ~0b01111111) | 0b01101110; break;
+  case  7: PORTB = (PORTB & ~0b01111111) | 0b01111110; break;
+  case  8: PORTB = (PORTB & ~0b01111111) | 0b01000001; break;
+  case  9: PORTB = (PORTB & ~0b01111111) | 0b00100001; break;
+  case 10: PORTB = (PORTB & ~0b01111111) | 0b01101010; break;
+  case 11: PORTB = (PORTB & ~0b01111111) | 0b01110010; break;
+  case 12: PORTB = (PORTB & ~0b01111111) | 0b01111100; break;
+  case 13: PORTB = (PORTB & ~0b01111111) | 0b01110100; break;
+  case 14: PORTB = (PORTB & ~0b01111111) | 0b01111000; break;
+  case 15: PORTB = (PORTB & ~0b01111111) | 0b01110000; break;
+  case 16: PORTB = (PORTB & ~0b01111111) | 0b01100000; break;
+  case 17: PORTB = (PORTB & ~0b01111111) | 0b01101000; break;
+  }
+}
diff --git a/keyboards/kitten_paw/readme.md b/keyboards/kitten_paw/readme.md
new file mode 100644
index 000000000..a6ef2a067
--- /dev/null
+++ b/keyboards/kitten_paw/readme.md
@@ -0,0 +1,32 @@
+kitten_paw keyboard firmware
+======================
+This is the firmware for the 2016 revision of the Kitten Paw controller by Bathroom Epiphanies.
+Most of the boilerplate code is the work of [BathroomEpiphanies](https://github.com/BathroomEpiphanies).
+
+NKRO doesn't work at the moment, I don't know if I will take the time to find out how to fix this, so far 6KRO is enough for me.
+
+## Quantum MK Firmware
+
+For the full Quantum feature list, see [the parent readme.md](/doc/readme.md).
+
+## Building
+
+Download or clone the whole firmware and navigate to the keyboards/kitten_paw folder. Once your dev env is setup, you'll be able to type `make` to generate your .hex - you can then use the Teensy Loader to program your .hex file. 
+
+Depending on which keymap you would like to use, you will have to compile slightly differently.
+
+### Default
+
+To build with the default keymap, simply run `make`.
+
+### Other Keymaps
+
+Several version of keymap are available in advance but you are recommended to define your favorite layout yourself. To define your own keymap create a folder with the name of your keymap in the keymaps folder, and see keymap documentation (you can find in top readme.md) and existant keymap files.
+
+To build the firmware binary hex file with a keymap just do `make` with `keymap` option like:
+
+```
+$ make keymap=[default|jack|<name>]
+```
+
+Keymaps follow the format **__keymap.c__** and are stored in folders in the `keymaps` folder, eg `keymaps/my_keymap/`
diff --git a/keyboards/planck/keymaps/experimental/Makefile b/keyboards/planck/keymaps/experimental/Makefile
index 877c4aed0..3a8250a9b 100644
--- a/keyboards/planck/keymaps/experimental/Makefile
+++ b/keyboards/planck/keymaps/experimental/Makefile
@@ -16,6 +16,7 @@ AUDIO_ENABLE = no           # Audio output on port C6
 UNICODE_ENABLE = no         # Unicode
 BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
 RGBLIGHT_ENABLE = yes        # Enable WS2812 RGB underlight.  Do not enable this with audio at the same time.
+ONEHAND_ENABLE = yes        # Enable one-hand typing
 
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
diff --git a/keyboards/planck/keymaps/experimental/keymap.c b/keyboards/planck/keymaps/experimental/keymap.c
index 2c1270094..569dbcc8a 100644
--- a/keyboards/planck/keymaps/experimental/keymap.c
+++ b/keyboards/planck/keymaps/experimental/keymap.c
@@ -70,7 +70,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
   {KC_TAB,  KC_Q,    KC_W,    KC_E,    KC_R,    KC_T,    KC_Y,    KC_U,    KC_I,    KC_O,    KC_P,    KC_BSPC},
   {KC_ESC,  KC_A,    KC_S,    KC_D,    KC_F,    KC_G,    KC_H,    KC_J,    KC_K,    KC_L,    KC_SCLN, KC_QUOT},
   {KC_LSFT, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_N,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, KC_ENT },
-  {KC_LEAD, KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_SPC,  KC_SPC,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT}
+  {KC_LEAD, KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_FN0,  KC_FN0,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT}
 },
 
 /* Colemak
@@ -88,7 +88,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
   {KC_TAB,  KC_Q,    KC_W,    KC_F,    KC_P,    KC_G,    KC_J,    KC_L,    KC_U,    KC_Y,    KC_SCLN, KC_BSPC},
   {KC_ESC,  KC_A,    KC_R,    KC_S,    KC_T,    KC_D,    KC_H,    KC_N,    KC_E,    KC_I,    KC_O,    KC_QUOT},
   {KC_LSFT, KC_Z,    KC_X,    KC_C,    KC_V,    KC_B,    KC_K,    KC_M,    KC_COMM, KC_DOT,  KC_SLSH, KC_ENT },
-  {KC_LEAD, KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_SPC,  KC_SPC,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT}
+  {KC_LEAD, KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_FN0,  KC_FN0,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT}
 },
 
 /* Dvorak
@@ -106,7 +106,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
   {KC_TAB,  KC_QUOT, KC_COMM, KC_DOT,  KC_P,    KC_Y,    KC_F,    KC_G,    KC_C,    KC_R,    KC_L,    KC_BSPC},
   {KC_ESC,  KC_A,    KC_O,    KC_E,    KC_U,    KC_I,    KC_D,    KC_H,    KC_T,    KC_N,    KC_S,    KC_SLSH},
   {KC_LSFT, KC_SCLN, KC_Q,    KC_J,    KC_K,    KC_X,    KC_B,    KC_M,    KC_W,    KC_V,    KC_Z,    KC_ENT },
-  {KC_LEAD, KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_SPC,  KC_SPC,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT}
+  {KC_LEAD, KC_LCTL, KC_LALT, KC_LGUI, LOWER,   KC_FN0,  KC_FN0,  RAISE,   KC_LEFT, KC_DOWN, KC_UP,   KC_RGHT}
 },
 
 /* Lower
@@ -186,7 +186,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
 };
 
 const uint16_t PROGMEM fn_actions[] = {
-
+  ACTION_SWAP_HANDS_TAP_KEY(KC_SPC),
 };
 
 #ifdef AUDIO_ENABLE
diff --git a/keyboards/planck/planck.c b/keyboards/planck/planck.c
index 8d70bb4e5..645b450d1 100644
--- a/keyboards/planck/planck.c
+++ b/keyboards/planck/planck.c
@@ -1,5 +1,15 @@
 #include "planck.h"
 
+#ifdef ONEHAND_ENABLE
+__attribute__ ((weak))
+const keypos_t hand_swap_config[MATRIX_ROWS][MATRIX_COLS] = {
+  {{11, 0}, {10, 0}, {9, 0}, {8, 0}, {7, 0}, {6, 0}, {5, 0}, {4, 0}, {3, 0}, {2, 0}, {1, 0}, {0, 0}},
+  {{11, 1}, {10, 1}, {9, 1}, {8, 1}, {7, 1}, {6, 1}, {5, 1}, {4, 1}, {3, 1}, {2, 1}, {1, 1}, {0, 1}},
+  {{11, 2}, {10, 2}, {9, 2}, {8, 2}, {7, 2}, {6, 2}, {5, 2}, {4, 2}, {3, 2}, {2, 2}, {1, 2}, {0, 2}},
+  {{11, 3}, {10, 3}, {9, 3}, {8, 3}, {7, 3}, {6, 3}, {5, 3}, {4, 3}, {3, 3}, {2, 3}, {1, 3}, {0, 3}},
+};
+#endif
+
 void matrix_init_kb(void) {
         // Turn status LED on
         DDRE |= (1<<6);
diff --git a/keyboards/preonic/preonic.c b/keyboards/preonic/preonic.c
index 889c3fc8f..d9c119b8d 100644
--- a/keyboards/preonic/preonic.c
+++ b/keyboards/preonic/preonic.c
@@ -1,5 +1,16 @@
 #include "preonic.h"
 
+#ifdef ONEHAND_ENABLE
+__attribute__ ((weak))
+const keypos_t hand_swap_config[MATRIX_ROWS][MATRIX_COLS] = {
+  {{11, 0}, {10, 0}, {9, 0}, {8, 0}, {7, 0}, {6, 0}, {5, 0}, {4, 0}, {3, 0}, {2, 0}, {1, 0}, {0, 0}},
+  {{11, 1}, {10, 1}, {9, 1}, {8, 1}, {7, 1}, {6, 1}, {5, 1}, {4, 1}, {3, 1}, {2, 1}, {1, 1}, {0, 1}},
+  {{11, 2}, {10, 2}, {9, 2}, {8, 2}, {7, 2}, {6, 2}, {5, 2}, {4, 2}, {3, 2}, {2, 2}, {1, 2}, {0, 2}},
+  {{11, 3}, {10, 3}, {9, 3}, {8, 3}, {7, 3}, {6, 3}, {5, 3}, {4, 3}, {3, 3}, {2, 3}, {1, 3}, {0, 3}},
+  {{11, 4}, {10, 4}, {9, 4}, {8, 4}, {7, 4}, {6, 4}, {5, 4}, {4, 4}, {3, 4}, {2, 4}, {1, 4}, {0, 4}},
+};
+#endif
+
 void matrix_init_kb(void) {
 
     // Turn status LED on
diff --git a/keyboards/readme.md b/keyboards/readme.md
index f6c90b1f6..4f1796219 100644
--- a/keyboards/readme.md
+++ b/keyboards/readme.md
@@ -39,6 +39,7 @@ These keyboards are part of the QMK repository, but their manufacturers are not
 * [hhkb](/keyboards/hhkb) &mdash; The Happy Hacking keyboard can be hacked with a custom controller to run QMK.
 * [jd45](/keyboards/jd45) &mdash; Another Geekhack community project, designed by jdcarpe.
 * [kc60](/keyboards/kc60) &mdash; A programmable Chinese-made keyboard, lost in the mists of time.
+* [kitten_paw](/keyboards/kitten_paw) &mdash; A replacement controller (2016 revision) for the Filco Majestouch by [Bathroom Epiphanies](https://github.com/BathroomEpiphanies)
 * [phantom](/keyboards/phantom) &mdash; A tenkeyless kit by Teel, also from Geekhack.
 * [retro_refit](/keyboards/retro_refit) &mdash; Another creation by IBNobody.
 * [satan](/keyboards/satan) &mdash; A GH60 variant.
diff --git a/keyboards/tv44/tv44.h b/keyboards/tv44/tv44.h
index 4c30174ac..65c0b4593 100644
--- a/keyboards/tv44/tv44.h
+++ b/keyboards/tv44/tv44.h
@@ -11,7 +11,7 @@
     K00, K01, K02, K03, K04, K05, K06, K07, K08, K09, K0A, K0B, \
     K10, K11, K12, K13, K14, K15, K16, K17, K18, K19, K1A, K1B, \
     K20, K21, K22, K23, K24, K25, K26, K27, K28, K29, K2A, K2B, \
-    K30, K31, K32, K33,           K37, K38,      K39,      K3B  \
+    K30, K31, K32, K33,           K37, K38,      K39, K3A, K3B  \
 ) \
 { \
     { K00,   K01,   K02,   K03,  K04,   K05,   K06,   K07,   K08,   K09,   K0A,   K0B }, \
diff --git a/quantum/process_keycode/process_unicode.c b/quantum/process_keycode/process_unicode.c
index 72c809c30..a1be8d2fc 100644
--- a/quantum/process_keycode/process_unicode.c
+++ b/quantum/process_keycode/process_unicode.c
@@ -18,6 +18,7 @@ void set_unicode_input_mode(uint8_t os_target)
   input_mode = os_target;
 }
 
+__attribute__((weak))
 void unicode_input_start (void) {
   switch(input_mode) {
   case UC_OSX:
@@ -40,6 +41,7 @@ void unicode_input_start (void) {
   wait_ms(UNICODE_TYPE_DELAY);
 }
 
+__attribute__((weak))
 void unicode_input_finish (void) {
   switch(input_mode) {
   case UC_OSX:
diff --git a/tmk_core/common.mk b/tmk_core/common.mk
index aa05b9491..429c57143 100644
--- a/tmk_core/common.mk
+++ b/tmk_core/common.mk
@@ -85,6 +85,10 @@ ifeq ($(strip $(BLUETOOTH_ENABLE)), yes)
     OPT_DEFS += -DBLUETOOTH_ENABLE
 endif
 
+ifeq ($(strip $(ONEHAND_ENABLE)), yes)
+    OPT_DEFS += -DONEHAND_ENABLE
+endif
+
 ifeq ($(strip $(KEYMAP_SECTION_ENABLE)), yes)
     OPT_DEFS += -DKEYMAP_SECTION_ENABLE
 
diff --git a/tmk_core/common/action.c b/tmk_core/common/action.c
index be6dea2b7..08ef22eb9 100644
--- a/tmk_core/common/action.c
+++ b/tmk_core/common/action.c
@@ -41,6 +41,12 @@ void action_exec(keyevent_t event)
         dprint("EVENT: "); debug_event(event); dprintln();
     }
 
+#ifdef ONEHAND_ENABLE
+    if (!IS_NOEVENT(event)) {
+        process_hand_swap(&event);
+    }
+#endif
+
     keyrecord_t record = { .event = event };
 
 #ifndef NO_ACTION_TAPPING
@@ -53,6 +59,26 @@ void action_exec(keyevent_t event)
 #endif
 }
 
+#ifdef ONEHAND_ENABLE
+bool swap_hands = false;
+
+void process_hand_swap(keyevent_t *event) {
+    static swap_state_row_t swap_state[MATRIX_ROWS];
+
+    keypos_t pos = event->key;
+    swap_state_row_t col_bit = (swap_state_row_t)1<<pos.col;
+    bool do_swap = event->pressed ? swap_hands :
+                                    swap_state[pos.row] & (col_bit);
+
+    if (do_swap) {
+        event->key = hand_swap_config[pos.row][pos.col];
+        swap_state[pos.row] |= col_bit;
+    } else {
+        swap_state[pos.row] &= ~(col_bit);
+    }
+}
+#endif
+
 #if !defined(NO_ACTION_LAYER) && defined(PREVENT_STUCK_MODIFIERS)
 bool disable_action_cache = false;
 
@@ -440,6 +466,54 @@ void process_action(keyrecord_t *record, action_t action)
 #endif
         case ACT_COMMAND:
             break;
+#ifdef ONEHAND_ENABLE
+        case ACT_SWAP_HANDS:
+            switch (action.swap.code) {
+                case OP_SH_TOGGLE:
+                    if (event.pressed) {
+                        swap_hands = !swap_hands;
+                    }
+                    break;
+                case OP_SH_ON_OFF:
+                    swap_hands = event.pressed;
+                    break;
+                case OP_SH_OFF_ON:
+                    swap_hands = !event.pressed;
+                    break;
+                case OP_SH_ON:
+                    if (!event.pressed) {
+                        swap_hands = true;
+                    }
+                    break;
+                case OP_SH_OFF:
+                    if (!event.pressed) {
+                        swap_hands = false;
+                    }
+                    break;
+    #ifndef NO_ACTION_TAPPING
+                case OP_SH_TAP_TOGGLE:
+                    /* tap toggle */
+                    if (tap_count > 0) {
+                        if (!event.pressed) {
+                            swap_hands = !swap_hands;
+                        }
+                    } else {
+                        swap_hands = event.pressed;
+                    }
+                    break;
+                default:
+                    if (tap_count > 0) {
+                        if (event.pressed) {
+                            register_code(action.swap.code);
+                        } else {
+                            unregister_code(action.swap.code);
+                        }
+                    } else {
+                        swap_hands = event.pressed;
+                    }
+    #endif
+            }
+#endif
 #ifndef NO_ACTION_FUNCTION
         case ACT_FUNCTION:
             action_function(record, action.func.id, action.func.opt);
@@ -652,6 +726,13 @@ bool is_tap_key(keypos_t key)
                     return true;
             }
             return false;
+        case ACT_SWAP_HANDS:
+            switch (action.swap.code) {
+                case 0x00 ... 0xdf:
+                case OP_SH_TAP_TOGGLE:
+                    return true;
+            }
+            return false;
         case ACT_MACRO:
         case ACT_FUNCTION:
             if (action.func.opt & FUNC_TAP) { return true; }
@@ -692,6 +773,7 @@ void debug_action(action_t action)
         case ACT_MACRO:             dprint("ACT_MACRO");             break;
         case ACT_COMMAND:           dprint("ACT_COMMAND");           break;
         case ACT_FUNCTION:          dprint("ACT_FUNCTION");          break;
+        case ACT_SWAP_HANDS:        dprint("ACT_SWAP_HANDS");        break;
         default:                    dprint("UNKNOWN");               break;
     }
     dprintf("[%X:%02X]", action.kind.param>>8, action.kind.param&0xff);
diff --git a/tmk_core/common/action.h b/tmk_core/common/action.h
index e8aa12a7c..b9bdfe642 100644
--- a/tmk_core/common/action.h
+++ b/tmk_core/common/action.h
@@ -65,6 +65,24 @@ bool process_record_quantum(keyrecord_t *record);
 #if !defined(NO_ACTION_LAYER) && defined(PREVENT_STUCK_MODIFIERS)
 extern bool disable_action_cache;
 #endif
+
+/* Code for handling one-handed key modifiers. */
+#ifdef ONEHAND_ENABLE
+extern bool swap_hands;
+extern const keypos_t hand_swap_config[MATRIX_ROWS][MATRIX_COLS];
+#if (MATRIX_COLS <= 8)
+typedef  uint8_t    swap_state_row_t;
+#elif (MATRIX_COLS <= 16)
+typedef  uint16_t   swap_state_row_t;
+#elif (MATRIX_COLS <= 32)
+typedef  uint32_t   swap_state_row_t;
+#else
+#error "MATRIX_COLS: invalid value"
+#endif
+
+void process_hand_swap(keyevent_t *record);
+#endif
+
 void process_record_nocache(keyrecord_t *record);
 void process_record(keyrecord_t *record);
 void process_action(keyrecord_t *record, action_t action);
diff --git a/tmk_core/common/action_code.h b/tmk_core/common/action_code.h
index ca729aaec..33da35f35 100644
--- a/tmk_core/common/action_code.h
+++ b/tmk_core/common/action_code.h
@@ -108,6 +108,8 @@ enum action_kind_id {
     /* Other Keys */
     ACT_USAGE           = 0b0100,
     ACT_MOUSEKEY        = 0b0101,
+    /* One-hand Support */
+    ACT_SWAP_HANDS      = 0b0110,
     /* Layer Actions */
     ACT_LAYER           = 0b1000,
     ACT_LAYER_TAP       = 0b1010, /* Layer  0-15 */
@@ -178,6 +180,11 @@ typedef union {
         uint8_t  opt    :4;
         uint8_t  kind   :4;
     } func;
+    struct action_swap {
+        uint8_t  code   :8;
+        uint8_t  opt   :4;
+        uint8_t  kind   :4;
+    } swap;
 } action_t;
 
 
@@ -295,6 +302,7 @@ enum backlight_opt {
     BACKLIGHT_STEP     = 3,
     BACKLIGHT_LEVEL    = 4,
 };
+
 /* Macro */
 #define ACTION_MACRO(id)                ACTION(ACT_MACRO, (id))
 #define ACTION_MACRO_TAP(id)            ACTION(ACT_MACRO, FUNC_TAP<<8 | (id))
@@ -306,7 +314,7 @@ enum backlight_opt {
 #define ACTION_BACKLIGHT_STEP()         ACTION(ACT_BACKLIGHT, BACKLIGHT_STEP << 8)
 #define ACTION_BACKLIGHT_LEVEL(level)   ACTION(ACT_BACKLIGHT, BACKLIGHT_LEVEL << 8 | (level))
 /* Command */
-#define ACTION_COMMAND(id, opt)         ACTION(ACT_COMMAND,  (opt)<<8 | (addr))
+#define ACTION_COMMAND(id, opt)         ACTION(ACT_COMMAND,  (opt)<<8 | (id))
 /* Function */
 enum function_opts {
     FUNC_TAP = 0x8,     /* indciates function is tappable */
@@ -314,5 +322,23 @@ enum function_opts {
 #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))
+/* OneHand Support */
+enum swap_hands_pram_tap_op {
+    OP_SH_TOGGLE = 0xF0,
+    OP_SH_TAP_TOGGLE,
+    OP_SH_ON_OFF,
+    OP_SH_OFF_ON,
+    OP_SH_OFF,
+    OP_SH_ON,
+};
+
+#define ACTION_SWAP_HANDS()             ACTION_SWAP_HANDS_ON_OFF()
+#define ACTION_SWAP_HANDS_TOGGLE()      ACTION(ACT_SWAP_HANDS, OP_SH_TOGGLE)
+#define ACTION_SWAP_HANDS_TAP_TOGGLE()  ACTION(ACT_SWAP_HANDS, OP_SH_TAP_TOGGLE)
+#define ACTION_SWAP_HANDS_TAP_KEY(key)  ACTION(ACT_SWAP_HANDS, key)
+#define ACTION_SWAP_HANDS_ON_OFF()      ACTION(ACT_SWAP_HANDS, OP_SH_ON_OFF)
+#define ACTION_SWAP_HANDS_OFF_ON()      ACTION(ACT_SWAP_HANDS, OP_SH_OFF_ON)
+#define ACTION_SWAP_HANDS_ON()          ACTION(ACT_SWAP_HANDS, OP_SH_ON)
+#define ACTION_SWAP_HANDS_OFF()         ACTION(ACT_SWAP_HANDS, OP_SH_OFF)
 
 #endif /* ACTION_CODE_H */