diff --git a/keyboards/ergo42/config.h b/keyboards/ergo42/config.h
new file mode 100644
index 00000000000..c910d8f24f0
--- /dev/null
+++ b/keyboards/ergo42/config.h
@@ -0,0 +1,24 @@
+/*
+Copyright 2012 Jun Wako <wakojun@gmail.com>
+Copyright 2015 Jack Humbert
+
+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"
+
+#endif
diff --git a/keyboards/ergo42/ergo42.c b/keyboards/ergo42/ergo42.c
new file mode 100644
index 00000000000..9954f5c4cdb
--- /dev/null
+++ b/keyboards/ergo42/ergo42.c
@@ -0,0 +1,16 @@
+#include "ergo42.h"
+
+#ifdef ONEHAND_ENABLE
+__attribute__ ((weak))
+const keypos_t hand_swap_config[MATRIX_ROWS][MATRIX_COLS] = {
+
+  {{0, 4}, {1, 4}, {2, 4}, {3, 4}, {4, 4}, {5, 4}, {6, 4}},
+  {{0, 5}, {1, 5}, {2, 5}, {3, 5}, {4, 5}, {5, 5}, {6, 5}},
+  {{0, 6}, {1, 6}, {2, 6}, {3, 6}, {4, 6}, {5, 6}, {6, 6}},
+  {{0, 7}, {1, 7}, {2, 7}, {3, 7}, {4, 7}, {5, 7}, {6, 7}},
+  {{0, 0}, {1, 0}, {2, 0}, {3, 0}, {4, 0}, {5, 0}, {6, 0}},
+  {{0, 1}, {1, 1}, {2, 1}, {3, 1}, {4, 1}, {5, 1}, {6, 1}},
+  {{0, 2}, {1, 2}, {2, 2}, {3, 2}, {4, 2}, {5, 2}, {6, 2}},
+  {{0, 3}, {1, 3}, {2, 3}, {3, 3}, {4, 3}, {5, 3}, {6, 3}},
+};
+#endif
diff --git a/keyboards/ergo42/ergo42.h b/keyboards/ergo42/ergo42.h
new file mode 100644
index 00000000000..5e4343cf0b9
--- /dev/null
+++ b/keyboards/ergo42/ergo42.h
@@ -0,0 +1,27 @@
+#ifndef ERGO42_H
+#define ERGO42_H
+
+#include "quantum.h"
+
+#ifdef KEYBOARD_ergo42_rev1
+    #include "rev1.h"
+#endif
+
+
+// Used to create a keymap using only KC_ prefixed keys
+#define KC_KEYMAP( \
+    L00, L01, L02, L03, L04, L05, L06, R00, R01, R02, R03, R04, R05, R06, \
+    L10, L11, L12, L13, L14, L15, L16, R10, R11, R12, R13, R14, R15, R16, \
+    L20, L21, L22, L23, L24, L25, L26, R20, R21, R22, R23, R24, R25, R26, \
+    L30, L31, L32, L33, L34, L35, L36, R30, R31, R32, R33, R34, R35, R36 \
+    ) \
+    KEYMAP( \
+        KC_##L00, KC_##L01, KC_##L02, KC_##L03, KC_##L04, KC_##L05, KC_##L06, KC_##R00, KC_##R01, KC_##R02, KC_##R03, KC_##R04, KC_##R05, KC_##R06, \
+        KC_##L10, KC_##L11, KC_##L12, KC_##L13, KC_##L14, KC_##L15, KC_##L16, KC_##R10, KC_##R11, KC_##R12, KC_##R13, KC_##R14, KC_##R15, KC_##R16, \
+        KC_##L20, KC_##L21, KC_##L22, KC_##L23, KC_##L24, KC_##L25, KC_##L26, KC_##R20, KC_##R21, KC_##R22, KC_##R23, KC_##R24, KC_##R25, KC_##R26, \
+        KC_##L30, KC_##L31, KC_##L32, KC_##L33, KC_##L34, KC_##L35, KC_##L36, KC_##R30, KC_##R31, KC_##R32, KC_##R33, KC_##R34, KC_##R35, KC_##R36 \
+    )
+
+#define KC_LAYOUT_ortho_4x14 KC_KEYMAP
+
+#endif
diff --git a/keyboards/ergo42/i2c.c b/keyboards/ergo42/i2c.c
new file mode 100644
index 00000000000..084c890c405
--- /dev/null
+++ b/keyboards/ergo42/i2c.c
@@ -0,0 +1,162 @@
+#include <util/twi.h>
+#include <avr/io.h>
+#include <stdlib.h>
+#include <avr/interrupt.h>
+#include <util/twi.h>
+#include <stdbool.h>
+#include "i2c.h"
+
+#ifdef USE_I2C
+
+// Limits the amount of we wait for any one i2c transaction.
+// Since were running SCL line 100kHz (=> 10μs/bit), and each transactions is
+// 9 bits, a single transaction will take around 90μs to complete.
+//
+// (F_CPU/SCL_CLOCK)  =>  # of μC cycles to transfer a bit
+// poll loop takes at least 8 clock cycles to execute
+#define I2C_LOOP_TIMEOUT (9+1)*(F_CPU/SCL_CLOCK)/8
+
+#define BUFFER_POS_INC() (slave_buffer_pos = (slave_buffer_pos+1)%SLAVE_BUFFER_SIZE)
+
+volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
+
+static volatile uint8_t slave_buffer_pos;
+static volatile bool slave_has_register_set = false;
+
+// Wait for an i2c operation to finish
+inline static
+void i2c_delay(void) {
+  uint16_t lim = 0;
+  while(!(TWCR & (1<<TWINT)) && lim < I2C_LOOP_TIMEOUT)
+    lim++;
+
+  // easier way, but will wait slightly longer
+  // _delay_us(100);
+}
+
+// Setup twi to run at 100kHz
+void i2c_master_init(void) {
+  // no prescaler
+  TWSR = 0;
+  // Set TWI clock frequency to SCL_CLOCK. Need TWBR>10.
+  // Check datasheets for more info.
+  TWBR = ((F_CPU/SCL_CLOCK)-16)/2;
+}
+
+// Start a transaction with the given i2c slave address. The direction of the
+// transfer is set with I2C_READ and I2C_WRITE.
+// returns: 0 => success
+//          1 => error
+uint8_t i2c_master_start(uint8_t address) {
+  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTA);
+
+  i2c_delay();
+
+  // check that we started successfully
+  if ( (TW_STATUS != TW_START) && (TW_STATUS != TW_REP_START))
+    return 1;
+
+  TWDR = address;
+  TWCR = (1<<TWINT) | (1<<TWEN);
+
+  i2c_delay();
+
+  if ( (TW_STATUS != TW_MT_SLA_ACK) && (TW_STATUS != TW_MR_SLA_ACK) )
+    return 1; // slave did not acknowledge
+  else
+    return 0; // success
+}
+
+
+// Finish the i2c transaction.
+void i2c_master_stop(void) {
+  TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
+
+  uint16_t lim = 0;
+  while(!(TWCR & (1<<TWSTO)) && lim < I2C_LOOP_TIMEOUT)
+    lim++;
+}
+
+// Write one byte to the i2c slave.
+// returns 0 => slave ACK
+//         1 => slave NACK
+uint8_t i2c_master_write(uint8_t data) {
+  TWDR = data;
+  TWCR = (1<<TWINT) | (1<<TWEN);
+
+  i2c_delay();
+
+  // check if the slave acknowledged us
+  return (TW_STATUS == TW_MT_DATA_ACK) ? 0 : 1;
+}
+
+// Read one byte from the i2c slave. If ack=1 the slave is acknowledged,
+// if ack=0 the acknowledge bit is not set.
+// returns: byte read from i2c device
+uint8_t i2c_master_read(int ack) {
+  TWCR = (1<<TWINT) | (1<<TWEN) | (ack<<TWEA);
+
+  i2c_delay();
+  return TWDR;
+}
+
+void i2c_reset_state(void) {
+  TWCR = 0;
+}
+
+void i2c_slave_init(uint8_t address) {
+  TWAR = address << 0; // slave i2c address
+  // TWEN  - twi enable
+  // TWEA  - enable address acknowledgement
+  // TWINT - twi interrupt flag
+  // TWIE  - enable the twi interrupt
+  TWCR = (1<<TWIE) | (1<<TWEA) | (1<<TWINT) | (1<<TWEN);
+}
+
+ISR(TWI_vect);
+
+ISR(TWI_vect) {
+  uint8_t ack = 1;
+  switch(TW_STATUS) {
+    case TW_SR_SLA_ACK:
+      // this device has been addressed as a slave receiver
+      slave_has_register_set = false;
+      break;
+
+    case TW_SR_DATA_ACK:
+      // this device has received data as a slave receiver
+      // The first byte that we receive in this transaction sets the location
+      // of the read/write location of the slaves memory that it exposes over
+      // i2c.  After that, bytes will be written at slave_buffer_pos, incrementing
+      // slave_buffer_pos after each write.
+      if(!slave_has_register_set) {
+        slave_buffer_pos = TWDR;
+        // don't acknowledge the master if this memory loctaion is out of bounds
+        if ( slave_buffer_pos >= SLAVE_BUFFER_SIZE ) {
+          ack = 0;
+          slave_buffer_pos = 0;
+        }
+        slave_has_register_set = true;
+      } else {
+        i2c_slave_buffer[slave_buffer_pos] = TWDR;
+        BUFFER_POS_INC();
+      }
+      break;
+
+    case TW_ST_SLA_ACK:
+    case TW_ST_DATA_ACK:
+      // master has addressed this device as a slave transmitter and is
+      // requesting data.
+      TWDR = i2c_slave_buffer[slave_buffer_pos];
+      BUFFER_POS_INC();
+      break;
+
+    case TW_BUS_ERROR: // something went wrong, reset twi state
+      TWCR = 0;
+    default:
+      break;
+  }
+  // Reset everything, so we are ready for the next TWI interrupt
+  TWCR |= (1<<TWIE) | (1<<TWINT) | (ack<<TWEA) | (1<<TWEN);
+}
+#endif
diff --git a/keyboards/ergo42/i2c.h b/keyboards/ergo42/i2c.h
new file mode 100644
index 00000000000..c15b6bc5065
--- /dev/null
+++ b/keyboards/ergo42/i2c.h
@@ -0,0 +1,49 @@
+#ifndef I2C_H
+#define I2C_H
+
+#include <stdint.h>
+
+#ifndef F_CPU
+#define F_CPU 16000000UL
+#endif
+
+#define I2C_READ 1
+#define I2C_WRITE 0
+
+#define I2C_ACK 1
+#define I2C_NACK 0
+
+#define SLAVE_BUFFER_SIZE 0x10
+
+// i2c SCL clock frequency
+#define SCL_CLOCK  400000L
+
+extern volatile uint8_t i2c_slave_buffer[SLAVE_BUFFER_SIZE];
+
+void i2c_master_init(void);
+uint8_t i2c_master_start(uint8_t address);
+void i2c_master_stop(void);
+uint8_t i2c_master_write(uint8_t data);
+uint8_t i2c_master_read(int);
+void i2c_reset_state(void);
+void i2c_slave_init(uint8_t address);
+
+
+static inline unsigned char i2c_start_read(unsigned char addr) {
+  return i2c_master_start((addr << 1) | I2C_READ);
+}
+
+static inline unsigned char i2c_start_write(unsigned char addr) {
+  return i2c_master_start((addr << 1) | I2C_WRITE);
+}
+
+// from SSD1306 scrips
+extern unsigned char i2c_rep_start(unsigned char addr);
+extern void i2c_start_wait(unsigned char addr);
+extern unsigned char i2c_readAck(void);
+extern unsigned char i2c_readNak(void);
+extern unsigned char i2c_read(unsigned char ack);
+
+#define i2c_read(ack)  (ack) ? i2c_readAck() : i2c_readNak();
+
+#endif
diff --git a/keyboards/ergo42/keymaps/default-macOS/config.h b/keyboards/ergo42/keymaps/default-macOS/config.h
new file mode 100644
index 00000000000..5a6261c4f7c
--- /dev/null
+++ b/keyboards/ergo42/keymaps/default-macOS/config.h
@@ -0,0 +1,37 @@
+/*
+This is the c configuration file for the keymap
+
+Copyright 2012 Jun Wako <wakojun@gmail.com>
+Copyright 2015 Jack Humbert
+
+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_USER_H
+#define CONFIG_USER_H
+
+#include "../../config.h"
+
+/* Use I2C or Serial, not both */
+
+#define USE_SERIAL
+// #define USE_I2C
+
+/* Select hand configuration */
+
+#define MASTER_LEFT
+// #define MASTER_RIGHT
+// #define EE_HANDS
+
+#endif
diff --git a/keyboards/ergo42/keymaps/default-macOS/keymap.c b/keyboards/ergo42/keymaps/default-macOS/keymap.c
new file mode 100644
index 00000000000..559551fd630
--- /dev/null
+++ b/keyboards/ergo42/keymaps/default-macOS/keymap.c
@@ -0,0 +1,98 @@
+#include "ergo42.h"
+#include "action_layer.h"
+#include "eeconfig.h"
+
+extern keymap_config_t keymap_config;
+
+#define BASE 0
+#define META 1
+#define SYMB 2
+#define GAME 3
+
+// Fillers to make layering more clear
+#define _______ KC_TRNS
+#define XXXXXXX KC_NO
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+/* BASE
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * | Tab  |   Q  |   W  |   E  |   R  |   T  |  [   |   |  ]   |   Y  |   U  |   I  |   O  |   P  |  @   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |   A  |   S  |   D  |   F  |   G  |  (   |   |  )   |   H  |   J  |   K  |   L  |   ;  |  :   |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |   Z  |   X  |   C  |   V  |   B  |  {   |   |  }   |   N  |   M  |   ,  |   .  |   /  |\/Sft |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc |ESC/  |Space/|Tab/  |   |Back  |Enter/| Del  |PrtSc |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |~SYMB |Cmd   |Shift |   |Space |~META |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+
+[BASE] = KEYMAP( \
+  KC_TAB,   KC_Q,    KC_W,   KC_E,    KC_R,             KC_T,          KC_RBRC,       KC_BSLS,    KC_Y,             KC_U,    KC_I,     KC_O,     KC_P,     KC_LBRC, \
+  KC_LALT,  KC_A,    KC_S,   KC_D,    KC_F,             KC_G,          S(KC_8),       S(KC_9),    KC_H,             KC_J,    KC_K,     KC_L,     KC_SCLN,  KC_QUOT, \
+  KC_LSFT,  KC_Z,    KC_X,   KC_C,    KC_V,             KC_B,          S(KC_RBRC),    S(KC_BSLS), KC_N,             KC_M,    KC_COMM,  KC_DOT,   KC_SLSH,  SFT_T(KC_RO), \
+  KC_LCTRL, KC_LGUI, KC_APP, KC_PSCR, LT(SYMB, KC_ESC), GUI_T(KC_SPC), SFT_T(KC_TAB), KC_BSPC,    LT(META, KC_ENT), KC_DELT, KC_PSCR,  TG(GAME), TG(SYMB), KC_JYEN \
+),
+
+/* META
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * |   1  |   2  |   3  |   4  |   5  |   6  |  [   |   |  ]   |   7  |   8  |   9  |   0  |   -  |  ^   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |  F1  |      |Muhen | Henk |      |  (   |   |  )   | Left | Down |  Up  |Right |      |      |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |  F2  |  F3  |  F4  |  F5  |  F6  |  {   |   |  }   |  F7  |  F8  |  F9  | F10  | F11  |\/Sft |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc |ESC/  |Space/|Tab/  |   |Back  |Enter/| Del  |Reset |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |~SYMB |Ctrl  |Shift |   |Space |~META |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+
+[META] = KEYMAP( \
+  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_F1,   XXXXXXX, KC_MHEN, KC_HENK, XXXXXXX, _______, _______, KC_LEFT, KC_DOWN, KC_UP, KC_RGHT, XXXXXXX, XXXXXXX, \
+  _______, KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   _______, _______, KC_F7,   KC_F8,   KC_F9, KC_F10,  KC_F11,  SFT_T(KC_RO), \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, RESET, _______, _______, _______ \
+),
+
+/* SYMB
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * |   !  |   "  |   #  |   $  |   %  |   &  |  [   |   |  ]   |   '  |   (  |   )  |   ~  |   =  |  ~   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |      |      |      |      |      |  (   |   |  )   |      |      |      |      |   +  |  *   |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |      |      |      |      |      |  {   |   |  }   |      |      |   <  |   >  |   ?  |  \   |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc |ESC/  |Space/|Tab/  |   |Back  |Enter/| Del  |PrtSc |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |~SYMB |Ctrl  |Shift |   |Space |~META |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+
+[SYMB] = KEYMAP( \
+  S(KC_1), S(KC_2), S(KC_3), S(KC_4), S(KC_5), S(KC_6), _______, _______, S(KC_7), S(KC_8), S(KC_9),    S(KC_0),   S(KC_MINS), S(KC_EQL), \
+  _______, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, _______, _______, XXXXXXX, XXXXXXX, XXXXXXX,    XXXXXXX,   S(KC_SCLN), S(KC_QUOT), \
+  _______, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, _______, _______, XXXXXXX, XXXXXXX, S(KC_COMM), S(KC_DOT), S(KC_SLSH), S(KC_RO), \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,    _______,   _______,    _______ \
+),
+
+/* GAME
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * | Tab  |   Q  |   W  |   E  |   R  |   T  |  [   |   |  ]   |   Y  |   U  |   I  |   O  |   P  |  @   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |   A  |   S  |   D  |   F  |   G  |  (   |   |  )   |   H  |   J  |   K  |   L  |   ;  |  :   |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |   Z  |   X  |   C  |   V  |   B  |  {   |   |  }   |   N  |   M  |   ,  |   .  |   /  |\/Sft |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc | ESC  |Space |Tab   |   |Back  |Enter | Del  |PrtSc |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |      |      |      |   |Space |      |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+[GAME] = KEYMAP( \
+  KC_TAB,   KC_Q,    KC_W,   KC_E,    KC_R,   KC_T,   KC_RBRC,    KC_BSLS,    KC_Y,   KC_U,    KC_I,     KC_O,    KC_P,    KC_LBRC, \
+  KC_LALT,  KC_A,    KC_S,   KC_D,    KC_F,   KC_G,   S(KC_8),    S(KC_9),    KC_H,   KC_J,    KC_K,     KC_L,    KC_SCLN, KC_QUOT, \
+  KC_LSFT,  KC_Z,    KC_X,   KC_C,    KC_V,   KC_B,   S(KC_RBRC), S(KC_BSLS), KC_N,   KC_M,    KC_COMM,  KC_DOT,  KC_SLSH, SFT_T(KC_RO), \
+  KC_LCTRL, KC_LGUI, KC_APP, KC_PSCR, KC_ESC, KC_SPC, KC_TAB,     KC_BSPC,    KC_ENT, KC_DELT, KC_PSCR,  _______, _______, KC_JYEN \
+)
+
+};
+
diff --git a/keyboards/ergo42/keymaps/default-macOS/rules.mk b/keyboards/ergo42/keymaps/default-macOS/rules.mk
new file mode 100644
index 00000000000..457a3d01d4a
--- /dev/null
+++ b/keyboards/ergo42/keymaps/default-macOS/rules.mk
@@ -0,0 +1,3 @@
+ifndef QUANTUM_DIR
+	include ../../../../Makefile
+endif
diff --git a/keyboards/ergo42/keymaps/default/config.h b/keyboards/ergo42/keymaps/default/config.h
new file mode 100644
index 00000000000..5a6261c4f7c
--- /dev/null
+++ b/keyboards/ergo42/keymaps/default/config.h
@@ -0,0 +1,37 @@
+/*
+This is the c configuration file for the keymap
+
+Copyright 2012 Jun Wako <wakojun@gmail.com>
+Copyright 2015 Jack Humbert
+
+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_USER_H
+#define CONFIG_USER_H
+
+#include "../../config.h"
+
+/* Use I2C or Serial, not both */
+
+#define USE_SERIAL
+// #define USE_I2C
+
+/* Select hand configuration */
+
+#define MASTER_LEFT
+// #define MASTER_RIGHT
+// #define EE_HANDS
+
+#endif
diff --git a/keyboards/ergo42/keymaps/default/keymap.c b/keyboards/ergo42/keymaps/default/keymap.c
new file mode 100644
index 00000000000..704cd47e1fe
--- /dev/null
+++ b/keyboards/ergo42/keymaps/default/keymap.c
@@ -0,0 +1,98 @@
+#include "ergo42.h"
+#include "action_layer.h"
+#include "eeconfig.h"
+
+extern keymap_config_t keymap_config;
+
+#define BASE 0
+#define META 1
+#define SYMB 2
+#define GAME 3
+
+// Fillers to make layering more clear
+#define _______ KC_TRNS
+#define XXXXXXX KC_NO
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+/* BASE
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * | Tab  |   Q  |   W  |   E  |   R  |   T  |  [   |   |  ]   |   Y  |   U  |   I  |   O  |   P  |  @   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |   A  |   S  |   D  |   F  |   G  |  (   |   |  )   |   H  |   J  |   K  |   L  |   ;  |  :   |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |   Z  |   X  |   C  |   V  |   B  |  {   |   |  }   |   N  |   M  |   ,  |   .  |   /  |\/Sft |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc |ESC/  |Space/|Tab/  |   |Back  |Enter/| Del  |PrtSc |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |~SYMB |RCtrl |Shift |   |Space |~META |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+
+[BASE] = KEYMAP( \
+  KC_TAB,   KC_Q,    KC_W,   KC_E,    KC_R,             KC_T,          KC_RBRC,       KC_BSLS,    KC_Y,             KC_U,    KC_I,     KC_O,     KC_P,     KC_LBRC, \
+  KC_LALT,  KC_A,    KC_S,   KC_D,    KC_F,             KC_G,          S(KC_8),       S(KC_9),    KC_H,             KC_J,    KC_K,     KC_L,     KC_SCLN,  KC_QUOT, \
+  KC_LSFT,  KC_Z,    KC_X,   KC_C,    KC_V,             KC_B,          S(KC_RBRC),    S(KC_BSLS), KC_N,             KC_M,    KC_COMM,  KC_DOT,   KC_SLSH,  SFT_T(KC_RO), \
+  KC_LCTRL, KC_LGUI, KC_APP, KC_PSCR, LT(SYMB, KC_ESC), RCTL_T(KC_SPC), SFT_T(KC_TAB), KC_BSPC,    LT(META, KC_ENT), KC_DELT, KC_PSCR,  TG(GAME), TG(SYMB), KC_JYEN \
+),
+
+/* META
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * |   1  |   2  |   3  |   4  |   5  |   6  |  [   |   |  ]   |   7  |   8  |   9  |   0  |   -  |  ^   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |  F1  |      |Muhen | Henk |      |  (   |   |  )   | Left | Down |  Up  |Right |      |      |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |  F2  |  F3  |  F4  |  F5  |  F6  |  {   |   |  }   |  F7  |  F8  |  F9  | F10  | F11  |\/Sft |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc |ESC/  |Space/|Tab/  |   |Back  |Enter/| Del  |Reset |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |~SYMB |RCtrl |Shift |   |Space |~META |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+
+[META] = KEYMAP( \
+  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_F1,   XXXXXXX, KC_MHEN, KC_HENK, XXXXXXX, _______, _______, KC_LEFT, KC_DOWN, KC_UP, KC_RGHT, XXXXXXX, XXXXXXX, \
+  _______, KC_F2,   KC_F3,   KC_F4,   KC_F5,   KC_F6,   _______, _______, KC_F7,   KC_F8,   KC_F9, KC_F10,  KC_F11,  SFT_T(KC_RO), \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, RESET, _______, _______, _______ \
+),
+
+/* SYMB
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * |   !  |   "  |   #  |   $  |   %  |   &  |  [   |   |  ]   |   '  |   (  |   )  |   ~  |   =  |  ~   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |      |      |      |      |      |  (   |   |  )   |      |      |      |      |   +  |  *   |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |      |      |      |      |      |  {   |   |  }   |      |      |   <  |   >  |   ?  |  \   |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc |ESC/  |Space/|Tab/  |   |Back  |Enter/| Del  |PrtSc |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |~SYMB |RCtrl |Shift |   |Space |~META |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+
+[SYMB] = KEYMAP( \
+  S(KC_1), S(KC_2), S(KC_3), S(KC_4), S(KC_5), S(KC_6), _______, _______, S(KC_7), S(KC_8), S(KC_9),    S(KC_0),   S(KC_MINS), S(KC_EQL), \
+  _______, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, _______, _______, XXXXXXX, XXXXXXX, XXXXXXX,    XXXXXXX,   S(KC_SCLN), S(KC_QUOT), \
+  _______, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, XXXXXXX, _______, _______, XXXXXXX, XXXXXXX, S(KC_COMM), S(KC_DOT), S(KC_SLSH), S(KC_RO), \
+  _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,    _______,   _______,    _______ \
+),
+
+/* GAME
+ * ,------------------------------------------------.   ,------------------------------------------------.
+ * | Tab  |   Q  |   W  |   E  |   R  |   T  |  [   |   |  ]   |   Y  |   U  |   I  |   O  |   P  |  @   |
+ * |------+------+------+------+------+------+------|   |-------------+------+------+------+------+------|
+ * | Alt  |   A  |   S  |   D  |   F  |   G  |  (   |   |  )   |   H  |   J  |   K  |   L  |   ;  |  :   |
+ * |------+------+------+------+------+------+------|   |------|------+------+------+------+------+------|
+ * | Sft  |   Z  |   X  |   C  |   V  |   B  |  {   |   |  }   |   N  |   M  |   ,  |   .  |   /  |\/Sft |
+ * |------+------+------+------+------+------+------|   |------+------+------+------+------+------+------|
+ * | Ctrl | GUI  |  App |PrtSc | ESC  |Space |Tab   |   |Back  |Enter | Del  |PrtSc |=>GAME|=>SYMB|  \   |
+ * |      |      |      |      |      |      |      |   |Space |      |      |      |      |      |      |
+ * `------------------------------------------------'   `------------------------------------------------'
+ */
+[GAME] = KEYMAP( \
+  KC_TAB,   KC_Q,    KC_W,   KC_E,    KC_R,   KC_T,   KC_RBRC,    KC_BSLS,    KC_Y,   KC_U,    KC_I,     KC_O,    KC_P,    KC_LBRC, \
+  KC_LALT,  KC_A,    KC_S,   KC_D,    KC_F,   KC_G,   S(KC_8),    S(KC_9),    KC_H,   KC_J,    KC_K,     KC_L,    KC_SCLN, KC_QUOT, \
+  KC_LSFT,  KC_Z,    KC_X,   KC_C,    KC_V,   KC_B,   S(KC_RBRC), S(KC_BSLS), KC_N,   KC_M,    KC_COMM,  KC_DOT,  KC_SLSH, SFT_T(KC_RO), \
+  KC_LCTRL, KC_LGUI, KC_APP, KC_PSCR, KC_ESC, KC_SPC, KC_TAB,     KC_BSPC,    KC_ENT, KC_DELT, KC_PSCR,  _______, _______, KC_JYEN \
+)
+
+};
+
diff --git a/keyboards/ergo42/keymaps/default/rules.mk b/keyboards/ergo42/keymaps/default/rules.mk
new file mode 100644
index 00000000000..457a3d01d4a
--- /dev/null
+++ b/keyboards/ergo42/keymaps/default/rules.mk
@@ -0,0 +1,3 @@
+ifndef QUANTUM_DIR
+	include ../../../../Makefile
+endif
diff --git a/keyboards/ergo42/matrix.c b/keyboards/ergo42/matrix.c
new file mode 100644
index 00000000000..47cda6fa806
--- /dev/null
+++ b/keyboards/ergo42/matrix.c
@@ -0,0 +1,469 @@
+/*
+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/>.
+*/
+
+/*
+ * scan matrix
+ */
+#include <stdint.h>
+#include <stdbool.h>
+#include <avr/io.h>
+#include "wait.h"
+#include "print.h"
+#include "debug.h"
+#include "util.h"
+#include "matrix.h"
+#include "split_util.h"
+#include "pro_micro.h"
+#include "config.h"
+#include "timer.h"
+
+#ifdef USE_I2C
+#  include "i2c.h"
+#else // USE_SERIAL
+#  include "serial.h"
+#endif
+
+#ifndef DEBOUNCING_DELAY
+#   define DEBOUNCING_DELAY 5
+#endif
+
+#if (DEBOUNCING_DELAY > 0)
+    static uint16_t debouncing_time;
+    static bool debouncing = false;
+#endif
+
+#if (MATRIX_COLS <= 8)
+#    define print_matrix_header()  print("\nr/c 01234567\n")
+#    define print_matrix_row(row)  print_bin_reverse8(matrix_get_row(row))
+#    define matrix_bitpop(i)       bitpop(matrix[i])
+#    define ROW_SHIFTER ((uint8_t)1)
+#else
+#    error "Currently only supports 8 COLS"
+#endif
+static matrix_row_t matrix_debouncing[MATRIX_ROWS];
+
+#define ERROR_DISCONNECT_COUNT 5
+
+#define ROWS_PER_HAND (MATRIX_ROWS/2)
+
+static uint8_t error_count = 0;
+
+static const uint8_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
+static const uint8_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
+
+/* matrix state(1:on, 0:off) */
+static matrix_row_t matrix[MATRIX_ROWS];
+static matrix_row_t matrix_debouncing[MATRIX_ROWS];
+
+#if (DIODE_DIRECTION == COL2ROW)
+    static void init_cols(void);
+    static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row);
+    static void unselect_rows(void);
+    static void select_row(uint8_t row);
+    static void unselect_row(uint8_t row);
+#elif (DIODE_DIRECTION == ROW2COL)
+    static void init_rows(void);
+    static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col);
+    static void unselect_cols(void);
+    static void unselect_col(uint8_t col);
+    static void select_col(uint8_t col);
+#endif
+__attribute__ ((weak))
+void matrix_init_quantum(void) {
+    matrix_init_kb();
+}
+
+__attribute__ ((weak))
+void matrix_scan_quantum(void) {
+    matrix_scan_kb();
+}
+
+__attribute__ ((weak))
+void matrix_init_kb(void) {
+    matrix_init_user();
+}
+
+__attribute__ ((weak))
+void matrix_scan_kb(void) {
+    matrix_scan_user();
+}
+
+__attribute__ ((weak))
+void matrix_init_user(void) {
+}
+
+__attribute__ ((weak))
+void matrix_scan_user(void) {
+}
+
+inline
+uint8_t matrix_rows(void)
+{
+    return MATRIX_ROWS;
+}
+
+inline
+uint8_t matrix_cols(void)
+{
+    return MATRIX_COLS;
+}
+
+void matrix_init(void)
+{
+    debug_enable = true;
+    debug_matrix = true;
+    debug_mouse = true;
+    // initialize row and col
+#if (DIODE_DIRECTION == COL2ROW)
+    unselect_rows();
+    init_cols();
+#elif (DIODE_DIRECTION == ROW2COL)
+    unselect_cols();
+    init_rows();
+#endif
+
+    TX_RX_LED_INIT;
+
+    // initialize matrix state: all keys off
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
+        matrix[i] = 0;
+        matrix_debouncing[i] = 0;
+    }
+
+    matrix_init_quantum();
+
+}
+
+uint8_t _matrix_scan(void)
+{
+    int offset = isLeftHand ? 0 : (ROWS_PER_HAND);
+#if (DIODE_DIRECTION == COL2ROW)
+    // Set row, read cols
+    for (uint8_t current_row = 0; current_row < ROWS_PER_HAND; current_row++) {
+#       if (DEBOUNCING_DELAY > 0)
+            bool matrix_changed = read_cols_on_row(matrix_debouncing+offset, current_row);
+
+            if (matrix_changed) {
+                debouncing = true;
+                debouncing_time = timer_read();
+                PORTD ^= (1 << 2);
+            }
+
+#       else
+            read_cols_on_row(matrix+offset, current_row);
+#       endif
+
+    }
+
+#elif (DIODE_DIRECTION == ROW2COL)
+    // Set col, read rows
+    for (uint8_t current_col = 0; current_col < MATRIX_COLS; current_col++) {
+#       if (DEBOUNCING_DELAY > 0)
+            bool matrix_changed = read_rows_on_col(matrix_debouncing+offset, current_col);
+            if (matrix_changed) {
+                debouncing = true;
+                debouncing_time = timer_read();
+            }
+#       else
+             read_rows_on_col(matrix+offset, current_col);
+#       endif
+
+    }
+#endif
+
+#   if (DEBOUNCING_DELAY > 0)
+        if (debouncing && (timer_elapsed(debouncing_time) > DEBOUNCING_DELAY)) {
+            for (uint8_t i = 0; i < ROWS_PER_HAND; i++) {
+                matrix[i+offset] = matrix_debouncing[i+offset];
+            }
+            debouncing = false;
+        }
+#   endif
+
+    return 1;
+}
+
+#ifdef USE_I2C
+
+// Get rows from other half over i2c
+int i2c_transaction(void) {
+    int slaveOffset = (isLeftHand) ? (ROWS_PER_HAND) : 0;
+
+    int err = i2c_master_start(SLAVE_I2C_ADDRESS + I2C_WRITE);
+    if (err) goto i2c_error;
+
+    // start of matrix stored at 0x00
+    err = i2c_master_write(0x00);
+    if (err) goto i2c_error;
+
+    // Start read
+    err = i2c_master_start(SLAVE_I2C_ADDRESS + I2C_READ);
+    if (err) goto i2c_error;
+
+    if (!err) {
+        int i;
+        for (i = 0; i < ROWS_PER_HAND-1; ++i) {
+            matrix[slaveOffset+i] = i2c_master_read(I2C_ACK);
+        }
+        matrix[slaveOffset+i] = i2c_master_read(I2C_NACK);
+        i2c_master_stop();
+    } else {
+i2c_error: // the cable is disconnceted, or something else went wrong
+        i2c_reset_state();
+        return err;
+    }
+
+    return 0;
+}
+
+#else // USE_SERIAL
+
+int serial_transaction(void) {
+    int slaveOffset = (isLeftHand) ? (ROWS_PER_HAND) : 0;
+
+    if (serial_update_buffers()) {
+        return 1;
+    }
+
+    for (int i = 0; i < ROWS_PER_HAND; ++i) {
+        matrix[slaveOffset+i] = serial_slave_buffer[i];
+    }
+    return 0;
+}
+#endif
+
+uint8_t matrix_scan(void)
+{
+    uint8_t ret = _matrix_scan();
+
+#ifdef USE_I2C
+    if( i2c_transaction() ) {
+#else // USE_SERIAL
+    if( serial_transaction() ) {
+#endif
+        // turn on the indicator led when halves are disconnected
+        TXLED1;
+
+        error_count++;
+
+        if (error_count > ERROR_DISCONNECT_COUNT) {
+            // reset other half if disconnected
+            int slaveOffset = (isLeftHand) ? (ROWS_PER_HAND) : 0;
+            for (int i = 0; i < ROWS_PER_HAND; ++i) {
+                matrix[slaveOffset+i] = 0;
+            }
+        }
+    } else {
+        // turn off the indicator led on no error
+        TXLED0;
+        error_count = 0;
+    }
+    matrix_scan_quantum();
+    return ret;
+}
+
+void matrix_slave_scan(void) {
+    _matrix_scan();
+
+    int offset = (isLeftHand) ? 0 : ROWS_PER_HAND;
+
+#ifdef USE_I2C
+    for (int i = 0; i < ROWS_PER_HAND; ++i) {
+        i2c_slave_buffer[i] = matrix[offset+i];
+    }
+#else // USE_SERIAL
+    for (int i = 0; i < ROWS_PER_HAND; ++i) {
+        serial_slave_buffer[i] = matrix[offset+i];
+    }
+#endif
+}
+
+bool matrix_is_modified(void)
+{
+    if (debouncing) return false;
+    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++) {
+        phex(row); print(": ");
+        pbin_reverse16(matrix_get_row(row));
+        print("\n");
+    }
+}
+
+uint8_t matrix_key_count(void)
+{
+    uint8_t count = 0;
+    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
+        count += bitpop16(matrix[i]);
+    }
+    return count;
+}
+
+#if (DIODE_DIRECTION == COL2ROW)
+
+static void init_cols(void)
+{
+    for(uint8_t x = 0; x < MATRIX_COLS; x++) {
+        uint8_t pin = col_pins[x];
+        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
+        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
+    }
+}
+
+static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row)
+{
+    // Store last value of row prior to reading
+    matrix_row_t last_row_value = current_matrix[current_row];
+
+    // Clear data in matrix row
+    current_matrix[current_row] = 0;
+
+    // Select row and wait for row selecton to stabilize
+    select_row(current_row);
+    wait_us(30);
+
+    // For each col...
+    for(uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
+
+        // Select the col pin to read (active low)
+        uint8_t pin = col_pins[col_index];
+        uint8_t pin_state = (_SFR_IO8(pin >> 4) & _BV(pin & 0xF));
+
+        // Populate the matrix row with the state of the col pin
+        current_matrix[current_row] |=  pin_state ? 0 : (ROW_SHIFTER << col_index);
+    }
+
+    // Unselect row
+    unselect_row(current_row);
+
+    return (last_row_value != current_matrix[current_row]);
+}
+
+static void select_row(uint8_t row)
+{
+    uint8_t pin = row_pins[row];
+    _SFR_IO8((pin >> 4) + 1) |=  _BV(pin & 0xF); // OUT
+    _SFR_IO8((pin >> 4) + 2) &= ~_BV(pin & 0xF); // LOW
+}
+
+static void unselect_row(uint8_t row)
+{
+    uint8_t pin = row_pins[row];
+    _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
+    _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
+}
+
+static void unselect_rows(void)
+{
+    for(uint8_t x = 0; x < ROWS_PER_HAND; x++) {
+        uint8_t pin = row_pins[x];
+        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
+        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
+    }
+}
+
+#elif (DIODE_DIRECTION == ROW2COL)
+
+static void init_rows(void)
+{
+    for(uint8_t x = 0; x < ROWS_PER_HAND; x++) {
+        uint8_t pin = row_pins[x];
+        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
+        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
+    }
+}
+
+static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col)
+{
+    bool matrix_changed = false;
+
+    // Select col and wait for col selecton to stabilize
+    select_col(current_col);
+    wait_us(30);
+
+    // For each row...
+    for(uint8_t row_index = 0; row_index < ROWS_PER_HAND; row_index++)
+    {
+
+        // Store last value of row prior to reading
+        matrix_row_t last_row_value = current_matrix[row_index];
+
+        // Check row pin state
+        if ((_SFR_IO8(row_pins[row_index] >> 4) & _BV(row_pins[row_index] & 0xF)) == 0)
+        {
+            // Pin LO, set col bit
+            current_matrix[row_index] |= (ROW_SHIFTER << current_col);
+        }
+        else
+        {
+            // Pin HI, clear col bit
+            current_matrix[row_index] &= ~(ROW_SHIFTER << current_col);
+        }
+
+        // Determine if the matrix changed state
+        if ((last_row_value != current_matrix[row_index]) && !(matrix_changed))
+        {
+            matrix_changed = true;
+        }
+    }
+
+    // Unselect col
+    unselect_col(current_col);
+
+    return matrix_changed;
+}
+
+static void select_col(uint8_t col)
+{
+    uint8_t pin = col_pins[col];
+    _SFR_IO8((pin >> 4) + 1) |=  _BV(pin & 0xF); // OUT
+    _SFR_IO8((pin >> 4) + 2) &= ~_BV(pin & 0xF); // LOW
+}
+
+static void unselect_col(uint8_t col)
+{
+    uint8_t pin = col_pins[col];
+    _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
+    _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
+}
+
+static void unselect_cols(void)
+{
+    for(uint8_t x = 0; x < MATRIX_COLS; x++) {
+        uint8_t pin = col_pins[x];
+        _SFR_IO8((pin >> 4) + 1) &= ~_BV(pin & 0xF); // IN
+        _SFR_IO8((pin >> 4) + 2) |=  _BV(pin & 0xF); // HI
+    }
+}
+
+#endif
diff --git a/keyboards/ergo42/readme.md b/keyboards/ergo42/readme.md
new file mode 100644
index 00000000000..9534bc71312
--- /dev/null
+++ b/keyboards/ergo42/readme.md
@@ -0,0 +1,16 @@
+# Ergo42
+
+![Ergo42](https://raw.githubusercontent.com/Biacco42/Ergo42/readme/readme_image/ergo42_image.jpg)
+
+__The Answer to the Ultimate Question of Life, the Universe, and at least Keyboards.__  
+A split 7x4 ortholinear keyboard. [Hardware project repo](https://github.com/Biacco42/Ergo42)
+
+Keyboard Maintainer: [Biacco42](https://github.com/Biacco42) [@Biacco42](https://twitter.com/Biacco42)  
+Hardware Supported: Ergo42 PCB, Pro Micro ATmega32u4  
+Hardware Availability: [Ergo42 PCB and case](https://github.com/Biacco42/Ergo42)
+
+Make example for this keyboard (after setting up your build environment):
+
+    make ergo42/rev1:default:avrdude
+
+See [build environment setup](https://docs.qmk.fm/build_environment_setup.html) then the [make instructions](https://docs.qmk.fm/make_instructions.html) for more information.
diff --git a/keyboards/ergo42/rev1/config.h b/keyboards/ergo42/rev1/config.h
new file mode 100644
index 00000000000..51cff095c7c
--- /dev/null
+++ b/keyboards/ergo42/rev1/config.h
@@ -0,0 +1,93 @@
+/*
+Copyright 2012 Jun Wako <wakojun@gmail.com>
+Copyright 2015 Jack Humbert
+Copyright 2017 Biacco42
+
+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 REV1_CONFIG_H
+#define REV1_CONFIG_H
+
+#include "config_common.h"
+
+/* USB Device descriptor parameter */
+#define VENDOR_ID       0xBC42
+#define PRODUCT_ID      0x0042
+#define DEVICE_VER      0x0100
+#define MANUFACTURER    Biacco42
+#define PRODUCT         Ergo42
+#define DESCRIPTION     The Answer to the Ultimate Question of Life, the Universe, and at least Keyboards
+
+/* key matrix size */
+// Rows are doubled-up
+#define MATRIX_ROWS 8
+#define MATRIX_COLS 7
+
+// wiring of each half
+#define MATRIX_ROW_PINS { D7, E6, B4, B5 }
+#define MATRIX_COL_PINS { F5, F6, F7, B1, B3, B2, B6 }
+// #define MATRIX_COL_PINS { B6, B2, B3, B1, F7, F6 } //uncomment this line and comment line above if you need to reverse left-to-right key order
+
+#define CATERINA_BOOTLOADER
+
+/* define tapping term */
+#define TAPPING_TERM 120
+
+/* define if matrix has ghost */
+//#define MATRIX_HAS_GHOST
+
+/* number of backlight levels */
+// #define BACKLIGHT_LEVELS 3
+
+/* Set 0 if debouncing isn't needed */
+#define DEBOUNCING_DELAY 5
+
+/* 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
+
+/* key combination for command */
+#define IS_COMMAND() ( \
+    keyboard_report->mods == (MOD_BIT(KC_LSHIFT) | MOD_BIT(KC_RSHIFT)) \
+)
+
+/* ws2812 RGB LED */
+#define RGB_DI_PIN D3
+#define RGBLIGHT_TIMER
+#define RGBLED_NUM 12    // Number of LEDs
+#define ws2812_PORTREG  PORTD
+#define ws2812_DDRREG   DDRD
+
+/*
+ * 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/ergo42/rev1/rev1.c b/keyboards/ergo42/rev1/rev1.c
new file mode 100644
index 00000000000..b4c51d5572f
--- /dev/null
+++ b/keyboards/ergo42/rev1/rev1.c
@@ -0,0 +1,39 @@
+#include "ergo42.h"
+
+#ifdef AUDIO_ENABLE
+    float tone_startup[][2] = SONG(STARTUP_SOUND);
+    float tone_goodbye[][2] = SONG(GOODBYE_SOUND);
+#endif
+
+#ifdef SSD1306OLED
+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);
+}
+#endif
+
+void matrix_init_kb(void) {
+
+    #ifdef AUDIO_ENABLE
+        _delay_ms(20); // gets rid of tick
+        PLAY_SONG(tone_startup);
+    #endif
+
+    // // green led on
+    // DDRD |= (1<<5);
+    // PORTD &= ~(1<<5);
+
+    // // orange led on
+    // DDRB |= (1<<0);
+    // PORTB &= ~(1<<0);
+
+	matrix_init_user();
+};
+
+void shutdown_user(void) {
+    #ifdef AUDIO_ENABLE
+        PLAY_SONG(tone_goodbye);
+	_delay_ms(150);
+	stop_all_notes();
+    #endif
+}
diff --git a/keyboards/ergo42/rev1/rev1.h b/keyboards/ergo42/rev1/rev1.h
new file mode 100644
index 00000000000..cbb510efb08
--- /dev/null
+++ b/keyboards/ergo42/rev1/rev1.h
@@ -0,0 +1,62 @@
+#ifndef REV1_H
+#define REV1_H
+
+#include "ergo42.h"
+
+//void promicro_bootloader_jmp(bool program);
+#include "quantum.h"
+
+
+#ifdef USE_I2C
+#include <stddef.h>
+#ifdef __AVR__
+	#include <avr/io.h>
+	#include <avr/interrupt.h>
+#endif
+#endif
+
+//void promicro_bootloader_jmp(bool program);
+
+#ifndef FLIP_HALF
+// Standard Keymap
+// (TRRS jack on the left half is to the right, TRRS jack on the right half is to the left)
+#define KEYMAP( \
+	L00, L01, L02, L03, L04, L05, L06, R00, R01, R02, R03, R04, R05, R06, \
+	L10, L11, L12, L13, L14, L15, L16, R10, R11, R12, R13, R14, R15, R16, \
+	L20, L21, L22, L23, L24, L25, L26, R20, R21, R22, R23, R24, R25, R26, \
+	L30, L31, L32, L33, L34, L35, L36, R30, R31, R32, R33, R34, R35, R36 \
+	) \
+	{ \
+		{ L00, L01, L02, L03, L04, L05, L06 }, \
+		{ L10, L11, L12, L13, L14, L15, L16 }, \
+		{ L20, L21, L22, L23, L24, L25, L26 }, \
+		{ L30, L31, L32, L33, L34, L35, L36 }, \
+		{ R06, R05, R04, R03, R02, R01, R00 }, \
+		{ R16, R15, R14, R13, R12, R11, R10 }, \
+		{ R26, R25, R24, R23, R22, R21, R20 }, \
+		{ R36, R35, R34, R33, R32, R31, R30 } \
+	}
+#else
+// Keymap with right side flipped
+// (TRRS jack on both halves are to the right)
+#define KEYMAP( \
+	L00, L01, L02, L03, L04, L05, L06, R00, R01, R02, R03, R04, R05, R06, \
+	L10, L11, L12, L13, L14, L15, L16, R10, R11, R12, R13, R14, R15, R16, \
+	L20, L21, L22, L23, L24, L25, L26, R20, R21, R22, R23, R24, R25, R26, \
+	L30, L31, L32, L33, L34, L35, L36, R30, R31, R32, R33, R34, R35, R36 \
+	) \
+	{ \
+		{ L00, L01, L02, L03, L04, L05, L06 }, \
+		{ L10, L11, L12, L13, L14, L15, L16 }, \
+		{ L20, L21, L22, L23, L24, L25, L26 }, \
+		{ L30, L31, L32, L33, L34, L35, L36 }, \
+		{ R00, R01, R02, R03, R04, R05, R06 }, \
+		{ R10, R11, R12, R13, R14, R15, R16 }, \
+		{ R20, R21, R22, R23, R24, R25, R26 }, \
+		{ R30, R31, R32, R33, R34, R35, R36 } \
+	}
+#endif
+
+#define LAYOUT_ortho_4x14 KEYMAP
+
+#endif
diff --git a/keyboards/ergo42/rev1/rules.mk b/keyboards/ergo42/rev1/rules.mk
new file mode 100644
index 00000000000..7b30c0beff2
--- /dev/null
+++ b/keyboards/ergo42/rev1/rules.mk
@@ -0,0 +1 @@
+BACKLIGHT_ENABLE = no
diff --git a/keyboards/ergo42/rules.mk b/keyboards/ergo42/rules.mk
new file mode 100644
index 00000000000..252411cab41
--- /dev/null
+++ b/keyboards/ergo42/rules.mk
@@ -0,0 +1,80 @@
+SRC += matrix.c \
+	   i2c.c \
+	   split_util.c \
+	   serial.c \
+	   ssd1306.c
+
+# MCU name
+#MCU = at90usb1287
+MCU = atmega32u4
+
+# 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 to "no" to disable the options, or define them in the Makefile in
+#   the appropriate keymap folder that will get included automatically
+#
+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 = no         # Console for debug(+400)
+COMMAND_ENABLE = yes        # Commands for debug and configuration
+NKRO_ENABLE = no            # Nkey Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
+BACKLIGHT_ENABLE = no      # Enable keyboard backlight functionality
+MIDI_ENABLE = no            # MIDI controls
+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 = no       # Enable WS2812 RGB underlight.  Do not enable this with audio at the same time.
+SUBPROJECT_rev1 = yes
+USE_I2C = yes
+# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
+
+CUSTOM_MATRIX = yes
+
+LAYOUTS = ortho_4x14
+
+DEFAULT_FOLDER = ergo42/rev1
diff --git a/keyboards/ergo42/serial.c b/keyboards/ergo42/serial.c
new file mode 100644
index 00000000000..74bcbb6bf6e
--- /dev/null
+++ b/keyboards/ergo42/serial.c
@@ -0,0 +1,228 @@
+/*
+ * WARNING: be careful changing this code, it is very timing dependent
+ */
+
+#ifndef F_CPU
+#define F_CPU 16000000
+#endif
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include <stdbool.h>
+#include "serial.h"
+
+#ifndef USE_I2C
+
+// Serial pulse period in microseconds. Its probably a bad idea to lower this
+// value.
+#define SERIAL_DELAY 24
+
+uint8_t volatile serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH] = {0};
+uint8_t volatile serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH] = {0};
+
+#define SLAVE_DATA_CORRUPT (1<<0)
+volatile uint8_t status = 0;
+
+inline static
+void serial_delay(void) {
+  _delay_us(SERIAL_DELAY);
+}
+
+inline static
+void serial_output(void) {
+  SERIAL_PIN_DDR |= SERIAL_PIN_MASK;
+}
+
+// make the serial pin an input with pull-up resistor
+inline static
+void serial_input(void) {
+  SERIAL_PIN_DDR  &= ~SERIAL_PIN_MASK;
+  SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
+}
+
+inline static
+uint8_t serial_read_pin(void) {
+  return !!(SERIAL_PIN_INPUT & SERIAL_PIN_MASK);
+}
+
+inline static
+void serial_low(void) {
+  SERIAL_PIN_PORT &= ~SERIAL_PIN_MASK;
+}
+
+inline static
+void serial_high(void) {
+  SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
+}
+
+void serial_master_init(void) {
+  serial_output();
+  serial_high();
+}
+
+void serial_slave_init(void) {
+  serial_input();
+
+  // Enable INT0
+  EIMSK |= _BV(INT0);
+  // Trigger on falling edge of INT0
+  EICRA &= ~(_BV(ISC00) | _BV(ISC01));
+}
+
+// Used by the master to synchronize timing with the slave.
+static
+void sync_recv(void) {
+  serial_input();
+  // This shouldn't hang if the slave disconnects because the
+  // serial line will float to high if the slave does disconnect.
+  while (!serial_read_pin());
+  serial_delay();
+}
+
+// Used by the slave to send a synchronization signal to the master.
+static
+void sync_send(void) {
+  serial_output();
+
+  serial_low();
+  serial_delay();
+
+  serial_high();
+}
+
+// Reads a byte from the serial line
+static
+uint8_t serial_read_byte(void) {
+  uint8_t byte = 0;
+  serial_input();
+  for ( uint8_t i = 0; i < 8; ++i) {
+    byte = (byte << 1) | serial_read_pin();
+    serial_delay();
+    _delay_us(1);
+  }
+
+  return byte;
+}
+
+// Sends a byte with MSB ordering
+static
+void serial_write_byte(uint8_t data) {
+  uint8_t b = 8;
+  serial_output();
+  while( b-- ) {
+    if(data & (1 << b)) {
+      serial_high();
+    } else {
+      serial_low();
+    }
+    serial_delay();
+  }
+}
+
+// interrupt handle to be used by the slave device
+ISR(SERIAL_PIN_INTERRUPT) {
+  sync_send();
+
+  uint8_t checksum = 0;
+  for (int i = 0; i < SERIAL_SLAVE_BUFFER_LENGTH; ++i) {
+    serial_write_byte(serial_slave_buffer[i]);
+    sync_send();
+    checksum += serial_slave_buffer[i];
+  }
+  serial_write_byte(checksum);
+  sync_send();
+
+  // wait for the sync to finish sending
+  serial_delay();
+
+  // read the middle of pulses
+  _delay_us(SERIAL_DELAY/2);
+
+  uint8_t checksum_computed = 0;
+  for (int i = 0; i < SERIAL_MASTER_BUFFER_LENGTH; ++i) {
+    serial_master_buffer[i] = serial_read_byte();
+    sync_send();
+    checksum_computed += serial_master_buffer[i];
+  }
+  uint8_t checksum_received = serial_read_byte();
+  sync_send();
+
+  serial_input(); // end transaction
+
+  if ( checksum_computed != checksum_received ) {
+    status |= SLAVE_DATA_CORRUPT;
+  } else {
+    status &= ~SLAVE_DATA_CORRUPT;
+  }
+}
+
+inline
+bool serial_slave_DATA_CORRUPT(void) {
+  return status & SLAVE_DATA_CORRUPT;
+}
+
+// Copies the serial_slave_buffer to the master and sends the
+// serial_master_buffer to the slave.
+//
+// Returns:
+// 0 => no error
+// 1 => slave did not respond
+int serial_update_buffers(void) {
+  // this code is very time dependent, so we need to disable interrupts
+  cli();
+
+  // signal to the slave that we want to start a transaction
+  serial_output();
+  serial_low();
+  _delay_us(1);
+
+  // wait for the slaves response
+  serial_input();
+  serial_high();
+  _delay_us(SERIAL_DELAY);
+
+  // check if the slave is present
+  if (serial_read_pin()) {
+    // slave failed to pull the line low, assume not present
+    sei();
+    return 1;
+  }
+
+  // if the slave is present syncronize with it
+  sync_recv();
+
+  uint8_t checksum_computed = 0;
+  // receive data from the slave
+  for (int i = 0; i < SERIAL_SLAVE_BUFFER_LENGTH; ++i) {
+    serial_slave_buffer[i] = serial_read_byte();
+    sync_recv();
+    checksum_computed += serial_slave_buffer[i];
+  }
+  uint8_t checksum_received = serial_read_byte();
+  sync_recv();
+
+  if (checksum_computed != checksum_received) {
+    sei();
+    return 1;
+  }
+
+  uint8_t checksum = 0;
+  // send data to the slave
+  for (int i = 0; i < SERIAL_MASTER_BUFFER_LENGTH; ++i) {
+    serial_write_byte(serial_master_buffer[i]);
+    sync_recv();
+    checksum += serial_master_buffer[i];
+  }
+  serial_write_byte(checksum);
+  sync_recv();
+
+  // always, release the line when not in use
+  serial_output();
+  serial_high();
+
+  sei();
+  return 0;
+}
+
+#endif
diff --git a/keyboards/ergo42/serial.h b/keyboards/ergo42/serial.h
new file mode 100644
index 00000000000..15fe4db7b4c
--- /dev/null
+++ b/keyboards/ergo42/serial.h
@@ -0,0 +1,26 @@
+#ifndef MY_SERIAL_H
+#define MY_SERIAL_H
+
+#include "config.h"
+#include <stdbool.h>
+
+/* TODO:  some defines for interrupt setup */
+#define SERIAL_PIN_DDR DDRD
+#define SERIAL_PIN_PORT PORTD
+#define SERIAL_PIN_INPUT PIND
+#define SERIAL_PIN_MASK _BV(PD0)
+#define SERIAL_PIN_INTERRUPT INT0_vect
+
+#define SERIAL_SLAVE_BUFFER_LENGTH MATRIX_ROWS/2
+#define SERIAL_MASTER_BUFFER_LENGTH 1
+
+// Buffers for master - slave communication
+extern volatile uint8_t serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH];
+extern volatile uint8_t serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH];
+
+void serial_master_init(void);
+void serial_slave_init(void);
+int serial_update_buffers(void);
+bool serial_slave_data_corrupt(void);
+
+#endif
diff --git a/keyboards/ergo42/split_util.c b/keyboards/ergo42/split_util.c
new file mode 100644
index 00000000000..346cbc90894
--- /dev/null
+++ b/keyboards/ergo42/split_util.c
@@ -0,0 +1,86 @@
+#include <avr/io.h>
+#include <avr/wdt.h>
+#include <avr/power.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include <avr/eeprom.h>
+#include "split_util.h"
+#include "matrix.h"
+#include "keyboard.h"
+#include "config.h"
+#include "timer.h"
+
+#ifdef USE_I2C
+#  include "i2c.h"
+#else
+#  include "serial.h"
+#endif
+
+volatile bool isLeftHand = true;
+
+static void setup_handedness(void) {
+  #ifdef EE_HANDS
+    isLeftHand = eeprom_read_byte(EECONFIG_HANDEDNESS);
+  #else
+    // I2C_MASTER_RIGHT is deprecated, use MASTER_RIGHT instead, since this works for both serial and i2c
+    #if defined(I2C_MASTER_RIGHT) || defined(MASTER_RIGHT)
+      isLeftHand = !has_usb();
+    #else
+      isLeftHand = has_usb();
+    #endif
+  #endif
+}
+
+static void keyboard_master_setup(void) {
+#ifdef USE_I2C
+    i2c_master_init();
+#ifdef SSD1306OLED
+    matrix_master_OLED_init ();
+#endif
+#else
+    serial_master_init();
+#endif
+}
+
+static void keyboard_slave_setup(void) {
+  timer_init();
+#ifdef USE_I2C
+    i2c_slave_init(SLAVE_I2C_ADDRESS);
+#else
+    serial_slave_init();
+#endif
+}
+
+bool has_usb(void) {
+   USBCON |= (1 << OTGPADE); //enables VBUS pad
+   _delay_us(5);
+   return (USBSTA & (1<<VBUS));  //checks state of VBUS
+}
+
+void split_keyboard_setup(void) {
+   setup_handedness();
+
+   if (has_usb()) {
+      keyboard_master_setup();
+   } else {
+      keyboard_slave_setup();
+   }
+   sei();
+}
+
+void keyboard_slave_loop(void) {
+   matrix_init();
+
+   while (1) {
+      matrix_slave_scan();
+   }
+}
+
+// this code runs before the usb and keyboard is initialized
+void matrix_setup(void) {
+    split_keyboard_setup();
+
+    if (!has_usb()) {
+        keyboard_slave_loop();
+    }
+}
diff --git a/keyboards/ergo42/split_util.h b/keyboards/ergo42/split_util.h
new file mode 100644
index 00000000000..595a0659e1d
--- /dev/null
+++ b/keyboards/ergo42/split_util.h
@@ -0,0 +1,20 @@
+#ifndef SPLIT_KEYBOARD_UTIL_H
+#define SPLIT_KEYBOARD_UTIL_H
+
+#include <stdbool.h>
+#include "eeconfig.h"
+
+#define SLAVE_I2C_ADDRESS           0x32
+
+extern volatile bool isLeftHand;
+
+// slave version of matix scan, defined in matrix.c
+void matrix_slave_scan(void);
+
+void split_keyboard_setup(void);
+bool has_usb(void);
+void keyboard_slave_loop(void);
+
+void matrix_master_OLED_init (void);
+
+#endif