add not-so-minidox handwire keyboard (#3061)

* add not-so-minidox handwire keyboard

* corrected keymap

* multiple adjustments to not_so_minidox keyboard

* remove I2C master left define

* update default layer set function

* move solenoid code into userspace

* minor adjustments to config.h

* update keymaps to utilize userspace

* move features and config to userspace, correct build issue

* correct solenoid pin

* adjust defaults for solenoid pin and enable

* default solenoid to on for not_so_minidox

* disable RGBLIGHT_SLEEP for xd75

* tweaking solenoid enable/disable in userspace and keymaps

16 files changed, 1334 insertions, 0 deletions

diff --git a/keyboards/handwired/not_so_minidox/config.h b/keyboards/handwired/not_so_minidox/config.h
new file mode 100644
index 0000000000..3c0af7bf76
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/config.h
@@ -0,0 +1,84 @@
+/*
+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      0x3060
+#define DEVICE_VER      0x0001
+#define MANUFACTURER    mtdjr
+#define PRODUCT         Not So MiniDox
+#define DESCRIPTION     A larger version of the MiniDox
+
+/* key matrix size */
+// Rows are doubled-up
+#define MATRIX_ROWS 8
+#define MATRIX_COLS 6
+
+/* COL2ROW or ROW2COL */
+#define DIODE_DIRECTION COL2ROW
+
+// wiring of each half
+#define MATRIX_ROW_PINS { D7, E6, B4, B5 }
+#define MATRIX_COL_PINS { B6, B2, B3, B1, F7, D4 }
+
+#define USE_SERIAL
+
+//#define EE_HANDS
+
+#define MASTER_LEFT
+//#define MASTER_RIGHT
+
+/* 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)) \
+)
+
+/* 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/handwired/not_so_minidox/i2c.c b/keyboards/handwired/not_so_minidox/i2c.c
new file mode 100644
index 0000000000..084c890c40
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/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/handwired/not_so_minidox/i2c.h b/keyboards/handwired/not_so_minidox/i2c.h
new file mode 100644
index 0000000000..c15b6bc506
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/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/handwired/not_so_minidox/keymaps/default/keymap.c b/keyboards/handwired/not_so_minidox/keymaps/default/keymap.c
new file mode 100644
index 0000000000..8ea36198a1
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/keymaps/default/keymap.c
@@ -0,0 +1,121 @@
+#include QMK_KEYBOARD_H
+
+extern keymap_config_t keymap_config;
+
+// Each layer gets a name for readability, which is then used in the keymap matrix below.
+// The underscores don't mean anything - you can have a layer called STUFF or any other name.
+// Layer names don't all need to be of the same length, obviously, and you can also skip them
+// entirely and just use numbers.
+#define _QWERTY 0
+#define _LOWER 1
+#define _RAISE 2
+#define _ADJUST 16
+
+enum custom_keycodes {
+  QWERTY = SAFE_RANGE,
+  LOWER,
+  RAISE,
+  ADJUST,
+};
+
+// Fillers to make layering more clear
+#define _______ KC_TRNS
+#define XXXXXXX KC_NO
+
+#define KC_LOWR LOWER
+#define KC_RASE RAISE
+#define KC_RST  RESET
+#define KC_CAD  LCTL(LALT(KC_DEL))
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+  [_QWERTY] = LAYOUT(
+// ,-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------.
+    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_LCTL,   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_LGUI,KC_LOWR, KC_SPC,       KC_SPC,KC_RASE,KC_RALT
+                          // `-------+-------+-------`     `-------+-------+-------`
+   ),
+
+  [_LOWER] = LAYOUT(
+// ,-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------.
+     KC_ESC,   KC_1,   KC_2,   KC_3,   KC_4,   KC_5,             KC_6,   KC_7,   KC_8,   KC_9,   KC_0, KC_DEL,
+// |-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------|
+    _______,_______,_______,_______,_______,_______,          _______,_______,_______,KC_LCBR,KC_RCBR,KC_BSLS,
+// |-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------|
+    _______,_______,_______,_______,_______,_______,          _______,_______,_______,_______,_______,_______,
+// '-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------'
+                              _______,_______,_______,      _______,_______,_______
+                          // `-------+-------+-------`     `-------+-------+-------`
+  ),
+
+  [_RAISE] = LAYOUT(
+ // ,-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------.
+      KC_GRV,KC_EXLM,  KC_AT,KC_HASH, KC_DLR,KC_PERC,          KC_CIRC,KC_AMPR,KC_ASTR,KC_LPRN,KC_RPRN, KC_DEL,
+ // |-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------|
+     _______,_______,_______,_______,KC_MINS, KC_EQL,          _______,  KC_UP,_______,KC_LBRC,KC_RBRC,KC_PIPE,
+ // |-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------|
+     _______,_______,_______,_______,_______,_______,          KC_LEFT,KC_DOWN,KC_RGHT,_______,_______,_______,
+ // '-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------'
+                               _______,_______,_______,      _______,_______,_______
+                           // `-------+-------+-------`     `-------+-------+-------`
+   ),
+  [_ADJUST] = LAYOUT(
+// ,-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------.
+    _______,_______,_______,_______, KC_RST,_______,          _______,_______,_______,_______,_______, KC_CAD,
+// |-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------|
+    _______,_______,_______,_______,_______,_______,          _______,_______,_______,_______,_______,_______,
+// |-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------|
+    _______,_______,_______,_______,_______,_______,          _______,_______,_______,_______,_______,_______,
+// '-------+-------+-------+-------+-------+-------.         ,-------+-------+-------+-------+-------+-------'
+                              _______,_______,_______,      _______,_______,_______
+                          // `-------+-------+-------`     `-------+-------+-------`
+  )
+};
+
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  switch (keycode) {
+    case QWERTY:
+      if (record->event.pressed) {
+        set_single_persistent_default_layer(_QWERTY);
+      }
+      return false;
+      break;
+    case LOWER:
+      if (record->event.pressed) {
+        layer_on(_LOWER);
+        update_tri_layer(_LOWER, _RAISE, _ADJUST);
+      } else {
+        layer_off(_LOWER);
+        update_tri_layer(_LOWER, _RAISE, _ADJUST);
+      }
+      return false;
+      break;
+    case RAISE:
+      if (record->event.pressed) {
+        layer_on(_RAISE);
+        update_tri_layer(_LOWER, _RAISE, _ADJUST);
+      } else {
+        layer_off(_RAISE);
+        update_tri_layer(_LOWER, _RAISE, _ADJUST);
+      }
+      return false;
+      break;
+    case ADJUST:
+      if (record->event.pressed) {
+        layer_on(_ADJUST);
+        update_tri_layer(_LOWER, _RAISE, _ADJUST);
+      } else {
+        layer_off(_ADJUST);
+        update_tri_layer(_LOWER, _RAISE, _ADJUST);
+      }
+      return false;
+      break;
+  }
+  return true;
+}
diff --git a/keyboards/handwired/not_so_minidox/keymaps/mtdjr/config.h b/keyboards/handwired/not_so_minidox/keymaps/mtdjr/config.h
new file mode 100644
index 0000000000..fa6151e108
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/keymaps/mtdjr/config.h
@@ -0,0 +1,11 @@
+#ifndef CONFIG_USER_H
+#define CONFIG_USER_H
+
+#include QMK_KEYBOARD_CONFIG_H
+
+#define SOLENOID_ENABLE
+#define SOLENOID_PIN F6
+#undef  SOLENOID_ACTIVE
+#define SOLENOID_ACTIVE true
+
+#endif
diff --git a/keyboards/handwired/not_so_minidox/keymaps/mtdjr/keymap.c b/keyboards/handwired/not_so_minidox/keymaps/mtdjr/keymap.c
new file mode 100644
index 0000000000..01c64d8701
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/keymaps/mtdjr/keymap.c
@@ -0,0 +1,56 @@
+#include QMK_KEYBOARD_H
+#include "mtdjr.h"
+
+extern keymap_config_t keymap_config;
+
+#define KC_LOCK TD(TD_ALTLOCK)
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+  [_QWERTY] = LAYOUT_kc(
+  // ,----+-----+-----+-----+-----+-----,         ,----+-----+-----+-----+-----+-----,
+       TAB,    Q,    W,    E,    R,    T,             Y,    U,    I,    O,    P, BSPC,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+      LCTL,    A,    S,    D,    F,    G,             H,    J,    K,    L, SCLN, QUOT,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+      LSFT,    Z,    X,    C,    V,    B,             N,    M, COMM,  DOT, SLSH,  ENT,
+  // |----+-----+-----+-----+-----+-----|-,     ,-|----+-----+-----+-----+-----+-----|
+                          LGUI, LOWR,  SPC,       SPC, RASE, LOCK
+  //                     `----+-----+-----`     `----+-----+-----`
+   ),
+
+  [_LOWER] = LAYOUT_kc(
+  // ,----+-----+-----+-----+-----+-----,         ,----+-----+-----+-----+-----+-----,
+       ESC,    1,    2,    3,    4,    5,             6,    7,    8,    9,    0,  DEL,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+          ,     ,     ,     ,     ,     ,              ,     ,     , LCBR, RCBR, BSLS,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+          ,     ,     , XCPY, XINS,     ,              ,     ,     ,     ,     ,     ,
+  // |----+-----+-----+-----+-----+-----|-,     ,-|----+-----+-----+-----+-----+-----|
+                              ,     ,     ,          ,     ,
+  //                     `----+-----+-----`     `----+-----+-----`
+  ),
+
+  [_RAISE] = LAYOUT_kc(
+  // ,----+-----+-----+-----+-----+-----,         ,----+-----+-----+-----+-----+-----,
+       GRV, EXLM,   AT, HASH,  DLR, PERC,          CIRC, AMPR, ASTR, LPRN, RPRN,  DEL,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+          ,     ,     ,     , MINS,  EQL,              ,     ,   UP, LBRC, RBRC, PIPE,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+          ,     ,     ,     ,     ,     ,              , LEFT, DOWN, RGHT,     ,     ,
+  // |----+-----+-----+-----+-----+-----|-,     ,-|----+-----+-----+-----+-----+-----|
+                              ,     ,     ,          ,     ,
+  //                     `----+-----+-----`     `----+-----+-----`
+   ),
+  [_ADJUST] = LAYOUT_kc(
+  // ,----+-----+-----+-----+-----+-----,         ,----+-----+-----+-----+-----+-----,
+      STOG, xxxx, xxxx, xxxx,  RST, xxxx,          ROOT, PPLY, PSEF, xxxx, xxxx,  CAD,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+      SDM,   SDP, SBOF, SBON, xxxx, xxxx,          xxxx, xxxx, xxxx, xxxx, xxxx, xxxx,
+  // |----+-----+-----+-----+-----+-----|         |----+-----+-----+-----+-----+-----|
+      xxxx, xxxx, xxxx, xxxx, xxxx, xxxx,          xxxx, xxxx, xxxx, xxxx, xxxx, xxxx,
+  // |----+-----+-----+-----+-----+-----|-,     ,-|----+-----+-----+-----+-----+-----|
+                          xxxx,     , xxxx,      xxxx,     , xxxx
+  //                     `----+-----+-----`     `----+-----+-----`
+  )
+};
diff --git a/keyboards/handwired/not_so_minidox/keymaps/mtdjr/rules.mk b/keyboards/handwired/not_so_minidox/keymaps/mtdjr/rules.mk
new file mode 100644
index 0000000000..e5ddcae8d9
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/keymaps/mtdjr/rules.mk
@@ -0,0 +1 @@
+TAP_DANCE_ENABLE = yes
diff --git a/keyboards/handwired/not_so_minidox/matrix.c b/keyboards/handwired/not_so_minidox/matrix.c
new file mode 100644
index 0000000000..27a38dca02
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/matrix.c
@@ -0,0 +1,307 @@
+/*
+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 <avr/wdt.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include "print.h"
+#include "debug.h"
+#include "util.h"
+#include "matrix.h"
+#include "split_util.h"
+#include "pro_micro.h"
+#include "config.h"
+
+#ifdef USE_I2C
+#  include "i2c.h"
+#else // USE_SERIAL
+#  include "serial.h"
+#endif
+
+#ifndef DEBOUNCE
+#  define DEBOUNCE	5
+#endif
+
+#define ERROR_DISCONNECT_COUNT 5
+
+static uint8_t debouncing = DEBOUNCE;
+static const int 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];
+
+static matrix_row_t read_cols(void);
+static void init_cols(void);
+static void unselect_rows(void);
+static void select_row(uint8_t row);
+
+
+__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
+    unselect_rows();
+    init_cols();
+
+    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)
+{
+    // Right hand is stored after the left in the matirx so, we need to offset it
+    int offset = isLeftHand ? 0 : (ROWS_PER_HAND);
+
+    for (uint8_t i = 0; i < ROWS_PER_HAND; i++) {
+        select_row(i);
+        _delay_us(30);  // without this wait read unstable value.
+        matrix_row_t cols = read_cols();
+        if (matrix_debouncing[i+offset] != cols) {
+            matrix_debouncing[i+offset] = cols;
+            debouncing = DEBOUNCE;
+        }
+        unselect_rows();
+    }
+
+    if (debouncing) {
+        if (--debouncing) {
+            _delay_ms(1);
+        } else {
+            for (uint8_t i = 0; i < ROWS_PER_HAND; i++) {
+                matrix[i+offset] = matrix_debouncing[i+offset];
+            }
+        }
+    }
+
+    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)
+{
+    int 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 : (MATRIX_ROWS / 2);
+
+#ifdef USE_I2C
+    for (int i = 0; i < ROWS_PER_HAND; ++i) {
+        /* i2c_slave_buffer[i] = matrix[offset+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;
+}
+
+static void  init_cols(void)
+{
+    for(int x = 0; x < MATRIX_COLS; x++) {
+        _SFR_IO8((col_pins[x] >> 4) + 1) &=  ~_BV(col_pins[x] & 0xF);
+        _SFR_IO8((col_pins[x] >> 4) + 2) |= _BV(col_pins[x] & 0xF);
+    }
+}
+
+static matrix_row_t read_cols(void)
+{
+    matrix_row_t result = 0;
+    for(int x = 0; x < MATRIX_COLS; x++) {
+        result |= (_SFR_IO8(col_pins[x] >> 4) & _BV(col_pins[x] & 0xF)) ? 0 : (1 << x);
+    }
+    return result;
+}
+
+static void unselect_rows(void)
+{
+    for(int x = 0; x < ROWS_PER_HAND; x++) {
+        _SFR_IO8((row_pins[x] >> 4) + 1) &=  ~_BV(row_pins[x] & 0xF);
+        _SFR_IO8((row_pins[x] >> 4) + 2) |= _BV(row_pins[x] & 0xF);
+    }
+}
+
+static void select_row(uint8_t row)
+{
+    _SFR_IO8((row_pins[row] >> 4) + 1) |=  _BV(row_pins[row] & 0xF);
+    _SFR_IO8((row_pins[row] >> 4) + 2) &= ~_BV(row_pins[row] & 0xF);
+}
diff --git a/keyboards/handwired/not_so_minidox/not_so_minidox.c b/keyboards/handwired/not_so_minidox/not_so_minidox.c
new file mode 100644
index 0000000000..898c9eaca8
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/not_so_minidox.c
@@ -0,0 +1 @@
+#include "not_so_minidox.h"
\ No newline at end of file
diff --git a/keyboards/handwired/not_so_minidox/not_so_minidox.h b/keyboards/handwired/not_so_minidox/not_so_minidox.h
new file mode 100644
index 0000000000..05e7bc4914
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/not_so_minidox.h
@@ -0,0 +1,42 @@
+#ifndef NOSOTMINIDOX_H
+#define NOSOTMINIDOX_H
+
+
+#include "quantum.h"
+
+#define LAYOUT( \
+	L00, L01, L02, L03, L04, L05,           R05, R04, R03, R02, R01, R00, \
+	L10, L11, L12, L13, L14, L15,           R15, R14, R13, R12, R11, R10, \
+	L20, L21, L22, L23, L24, L25,           R25, R24, R23, R22, R21, R20, \
+											LT1, LT2, LT3, RT3, RT2, RT1 \
+	) \
+	{ \
+		{ L00, L01, L02, L03, L04, L05 }, \
+		{ L10, L11, L12, L13, L14, L15 }, \
+		{ L20, L21, L22, L23, L24, L25 }, \
+		{ KC_NO, KC_NO, KC_NO, LT1, LT2, LT3 }, \
+		{ R00, R01, R02, R03, R04, R05 }, \
+		{ R10, R11, R12, R13, R14, R15 }, \
+		{ R20, R21, R22, R23, R24, R25 }, \
+		{ KC_NO, KC_NO, KC_NO, RT1, RT2, RT3 }, \
+	}
+
+// Used to create a keymap using only KC_ prefixed keys
+#define LAYOUT_kc( \
+	L00, L01, L02, L03, L04, L05,           R05, R04, R03, R02, R01, R00, \
+	L10, L11, L12, L13, L14, L15,           R15, R14, R13, R12, R11, R10, \
+	L20, L21, L22, L23, L24, L25,           R25, R24, R23, R22, R21, R20, \
+											LT1, LT2, LT3, RT3, RT2, RT1 \
+	) \
+	{ \
+		{ KC_##L00, KC_##L01, KC_##L02, KC_##L03, KC_##L04, KC_##L05 }, \
+		{ KC_##L10, KC_##L11, KC_##L12, KC_##L13, KC_##L14, KC_##L15 }, \
+		{ KC_##L20, KC_##L21, KC_##L22, KC_##L23, KC_##L24, KC_##L25 }, \
+		{ KC_NO, KC_NO, KC_NO, KC_##LT1, KC_##LT2, KC_##LT3 }, \
+		{ KC_##R00, KC_##R01, KC_##R02, KC_##R03, KC_##R04, KC_##R05 }, \
+		{ KC_##R10, KC_##R11, KC_##R12, KC_##R13, KC_##R14, KC_##R15 }, \
+		{ KC_##R20, KC_##R21, KC_##R22, KC_##R23, KC_##R24, KC_##R25 }, \
+		{ KC_NO, KC_NO, KC_NO, KC_##RT1, KC_##RT2, KC_##RT3 }, \
+	}
+
+#endif
diff --git a/keyboards/handwired/not_so_minidox/readme.md b/keyboards/handwired/not_so_minidox/readme.md
new file mode 100644
index 0000000000..fbfa7b7be0
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/readme.md
@@ -0,0 +1,71 @@
+not_so_minidox
+=====
+
+![not_so_minidox]()
+
+A slightly larger version of the MiniDox
+
+Keyboard Maintainer: mtdjr
+Hardware Supported: None yet/ProMicro
+
+Make example for this keyboard (after setting up your build environment):
+
+    make not_so_minidox/rev1:default
+
+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.
+
+Flashing
+-------
+Note: Most of this is copied from the Let's Split readme, because it is awesome
+
+From the root directory run `make PROJECT:KEYMAP:avrdude` for automatic serial port resolution and flashing.
+Example: `make not_so_minidox/rev1:default:avrdude`
+
+Choosing which board to plug the USB cable into (choosing Master)
+--------
+Because the two boards are identical, the firmware has logic to differentiate the left and right board.
+
+It uses two strategies to figure things out: look at the EEPROM (memory on the chip) or looks if the current board has the usb cable.
+
+The EEPROM approach requires additional setup (flashing the eeeprom) but allows you to swap the usb cable to either side.
+
+The USB cable approach is easier to setup and if you just want the usb cable on the left board, you do not need to do anything extra.
+
+### Setting the left hand as master
+If you always plug the usb cable into the left board, nothing extra is needed as this is the default. Comment out `EE_HANDS` and comment out `I2C_MASTER_RIGHT` or `MASTER_RIGHT` if for some reason it was set.
+
+### Setting the right hand as master
+If you always plug the usb cable into the right board, add an extra flag to your `config.h`
+```
+ #define MASTER_RIGHT
+```
+
+### Setting EE_hands to use either hands as master
+If you define `EE_HANDS` in your `config.h`, you will need to set the
+EEPROM for the left and right halves.
+
+The EEPROM is used to store whether the
+half is left handed or right handed. This makes it so that the same firmware
+file will run on both hands instead of having to flash left and right handed
+versions of the firmware to each half. To flash the EEPROM file for the left
+half run:
+```
+avrdude -p atmega32u4 -P $(COM_PORT) -c avr109 -U eeprom:w:eeprom-lefthand.eep
+// or the equivalent in dfu-programmer
+
+```
+and similarly for right half
+```
+avrdude -p atmega32u4 -P $(COM_PORT) -c avr109 -U eeprom:w:eeprom-righhand.eep
+// or the equivalent in dfu-programmer
+```
+
+NOTE: replace `$(COM_PORT)` with the port of your device (e.g. `/dev/ttyACM0`)
+
+After you have flashed the EEPROM, you then need to set `EE_HANDS` in your config.h, rebuild the hex files and reflash.
+
+Note that you need to program both halves, but you have the option of using
+different keymaps for each half. You could program the left half with a QWERTY
+layout and the right half with a Colemak layout using bootmagic's default layout option.
+Then if you connect the left half to a computer by USB the keyboard will use QWERTY and Colemak when the
+right half is connected.
diff --git a/keyboards/handwired/not_so_minidox/rules.mk b/keyboards/handwired/not_so_minidox/rules.mk
new file mode 100644
index 0000000000..fe4cc014e7
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/rules.mk
@@ -0,0 +1,71 @@
+SRC += matrix.c \
+	   i2c.c \
+	   split_util.c \
+	   serial.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)
+
+# Bootloader
+#     This definition is optional, and if your keyboard supports multiple bootloaders of
+#     different sizes, comment this out, and the correct address will be loaded
+#     automatically (+60). See bootloader.mk for all options.
+BOOTLOADER = caterina
+
+# Interrupt driven control endpoint task(+60)
+OPT_DEFS += -DINTERRUPT_CONTROL_ENDPOINT
+
+# 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 ?= no       # 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.
+USE_I2C ?= no
+# 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
diff --git a/keyboards/handwired/not_so_minidox/serial.c b/keyboards/handwired/not_so_minidox/serial.c
new file mode 100644
index 0000000000..74bcbb6bf6
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/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/handwired/not_so_minidox/serial.h b/keyboards/handwired/not_so_minidox/serial.h
new file mode 100644
index 0000000000..15fe4db7b4
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/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/handwired/not_so_minidox/split_util.c b/keyboards/handwired/not_so_minidox/split_util.c
new file mode 100644
index 0000000000..39639c3b4b
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/split_util.c
@@ -0,0 +1,84 @@
+#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"
+
+#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) {
+#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/handwired/not_so_minidox/split_util.h b/keyboards/handwired/not_so_minidox/split_util.h
new file mode 100644
index 0000000000..595a0659e1
--- /dev/null
+++ b/keyboards/handwired/not_so_minidox/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