[Keyboard] add claw44 keyboard (#5511)

* add claw44 keyboard

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/lib/layer_state_reader.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/readme.md

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Remove unnecessary code because of default value

* Move layer definition

* Update keyboards/claw44/keymaps/default/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/keymaps/yfuku/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/readme.md

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* default keymap. LAYOUT_kc -> LAYOUT macro

* Move rules.mk from keymaps to keyboard level.

* add Hardware Supported, Hardware Availability

* Update keyboards/claw44/keymaps/default/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Update keyboards/claw44/keymaps/yfuku/keymap.c

Co-Authored-By: yfuku <30647434+yfuku@users.noreply.github.com>

* Remove depreciated function

33 files changed, 3044 insertions, 0 deletions

diff --git a/keyboards/claw44/claw44.c b/keyboards/claw44/claw44.c
new file mode 100644
index 000000000..f564fb623
--- /dev/null
+++ b/keyboards/claw44/claw44.c
@@ -0,0 +1,10 @@
+#include "claw44.h"
+#include "ssd1306.h"
+
+bool process_record_kb(uint16_t keycode, keyrecord_t *record) {
+#ifdef SSD1306OLED
+  return process_record_gfx(keycode,record) && process_record_user(keycode, record);
+#else
+  return process_record_user(keycode, record);
+#endif
+}
diff --git a/keyboards/claw44/claw44.h b/keyboards/claw44/claw44.h
new file mode 100644
index 000000000..4ca25fcb2
--- /dev/null
+++ b/keyboards/claw44/claw44.h
@@ -0,0 +1,5 @@
+#pragma once
+
+#ifdef KEYBOARD_claw44_rev1
+  #include "rev1.h"
+#endif
diff --git a/keyboards/claw44/config.h b/keyboards/claw44/config.h
new file mode 100644
index 000000000..fb1cdf396
--- /dev/null
+++ b/keyboards/claw44/config.h
@@ -0,0 +1,28 @@
+/*
+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/>.
+*/
+
+#pragma once
+
+#include "config_common.h"
+#include <serial_config.h>
+
+#define USE_I2C
+#define USE_SERIAL
+
+#define NO_ACTION_MACRO
+#define NO_ACTION_FUNCTION
diff --git a/keyboards/claw44/i2c.c b/keyboards/claw44/i2c.c
new file mode 100644
index 000000000..4bee5c639
--- /dev/null
+++ b/keyboards/claw44/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 or 400kHz (see ./i2c.h SCL_CLOCK)
+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/claw44/i2c.h b/keyboards/claw44/i2c.h
new file mode 100644
index 000000000..710662c7a
--- /dev/null
+++ b/keyboards/claw44/i2c.h
@@ -0,0 +1,46 @@
+#pragma once
+
+#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 400kHz
+#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();
diff --git a/keyboards/claw44/keymaps/default/config.h b/keyboards/claw44/keymaps/default/config.h
new file mode 100644
index 000000000..eff6ad3c7
--- /dev/null
+++ b/keyboards/claw44/keymaps/default/config.h
@@ -0,0 +1,35 @@
+/*
+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/>.
+*/
+
+#pragma once
+
+//#define USE_MATRIX_I2C
+
+/* Select hand configuration */
+
+#define MASTER_LEFT
+// #define MASTER_RIGHT
+// #define EE_HANDS
+
+#define SSD1306OLED
+
+#define USE_SERIAL_PD2
+
+#define TAPPING_TERM 200
diff --git a/keyboards/claw44/keymaps/default/keymap.c b/keyboards/claw44/keymaps/default/keymap.c
new file mode 100644
index 000000000..c34657125
--- /dev/null
+++ b/keyboards/claw44/keymaps/default/keymap.c
@@ -0,0 +1,169 @@
+#include QMK_KEYBOARD_H
+#ifdef PROTOCOL_LUFA
+  #include "lufa.h"
+  #include "split_util.h"
+#endif
+#ifdef SSD1306OLED
+  #include "ssd1306.h"
+#endif
+
+extern keymap_config_t keymap_config;
+
+extern uint8_t is_master;
+
+// 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.
+
+enum custom_keycodes {
+  QWERTY = SAFE_RANGE,
+  LOWER,
+  RAISE
+};
+
+enum macro_keycodes {
+  KC_SAMPLEMACRO,
+};
+
+#define KC_ KC_TRNS
+#define KC_RST RESET
+#define KC_L_SPC LT(_LOWER, KC_SPC) // lower
+#define KC_R_ENT LT(_RAISE, KC_ENT) // raise
+#define KC_G_JA LGUI_T(KC_LANG1) // cmd or win
+#define KC_G_EN LGUI_T(KC_LANG2) // cmd or win
+#define KC_C_BS LCTL_T(KC_BSPC) // ctrl
+#define KC_A_DEL ALT_T(KC_DEL) // alt
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+  [_QWERTY] = LAYOUT( \
+  //,--------+--------+---------+--------+---------+--------.   ,--------+---------+--------+---------+--------+--------.
+     KC_ESC , KC_Q   , KC_W    , KC_E   , KC_R    , KC_T   ,     KC_Y   , KC_U    , KC_I   , KC_O    , KC_P   , KC_MINS,
+  //|--------+--------+---------+--------+---------+--------|   |--------+---------+--------+---------+--------+--------|
+     KC_TAB , 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_RSFT,
+  //`--------+--------+---------+--------+---------+--------/   \--------+---------+--------+---------+--------+--------'
+                       KC_A_DEL, KC_G_EN, KC_L_SPC, KC_C_BS,     KC_C_BS, KC_R_ENT, KC_G_JA, KC_A_DEL
+  //                 `----------+--------+---------+--------'   `--------+---------+--------+---------'
+  ),
+
+  //   \ ^ ! & |  @ = + * % -
+  // ( # $ " ' ~  ← ↓ ↑ → ` )
+  //         { [  ] }
+
+  [_RAISE] = LAYOUT( \
+  //,--------+--------+--------+--------+--------+--------.   ,--------+--------+--------+--------+--------+--------.
+     _______, KC_BSLS, KC_CIRC, KC_EXLM, KC_AMPR, KC_PIPE,     KC_AT  , KC_EQL , KC_PLUS, KC_ASTR, KC_PERC, KC_MINS,
+  //|--------+--------+--------+--------+--------+--------|   |--------+--------+--------+--------+--------+--------|
+     KC_LPRN, KC_HASH, KC_DLR , KC_DQT , KC_QUOT, KC_TILD,     KC_LEFT, KC_DOWN,  KC_UP , KC_RGHT, KC_GRV , KC_RPRN,
+  //|--------+--------+--------+--------+--------+--------|   |--------+--------+--------+--------+--------+--------|
+     _______, _______, _______, _______, KC_LCBR, KC_LBRC,     KC_RBRC, KC_RCBR, _______, _______, _______, _______,
+  //`--------+--------+--------+--------+--------+--------/   \--------+--------+--------+--------+--------+--------'
+                       _______, _______, _______, _______,     _______, _______, _______, RESET
+  //                  `--------+--------+--------+--------'   `--------+--------+--------+--------'
+  ),
+
+  [_LOWER] = LAYOUT( \
+  //,--------+--------+--------+--------+--------+--------.   ,--------+--------+--------+--------+--------+--------.
+     KC_F1  , KC_F2  , KC_F3  , KC_F4  , KC_F5  , KC_F6  ,     _______, KC_EQL , KC_PLUS, KC_ASTR, KC_PERC, KC_MINS,
+  //|--------+--------+--------+--------+--------+--------|   |--------+--------+--------+--------+--------+--------|
+     _______, KC_1   , KC_2   , KC_3   , KC_4   , KC_5   ,     KC_6   , KC_7   , KC_8   , KC_9   , KC_0   , _______,
+  //|--------+--------+--------+--------+--------+--------|   |--------+--------+--------+--------+--------+--------|
+     KC_F7  , KC_F8  , KC_F9  , KC_F10 , KC_F11 , KC_F12 ,     _______, _______, KC_COMM, KC_DOT , KC_SLSH, _______,
+  //`--------+--------+--------+--------+--------+--------/   \--------+--------+--------+--------+--------+--------'
+                       RESET  , _______, _______, _______,     _______, _______, _______, _______
+  //                  `--------+--------+--------+--------'   `--------+--------+--------+--------'
+  ),
+};
+
+void matrix_init_user(void) {
+  //SSD1306 OLED init, make sure to add #define SSD1306OLED in config.h
+  #ifdef SSD1306OLED
+    iota_gfx_init(!has_usb());   // turns on the display
+  #endif
+}
+
+//SSD1306 OLED update loop, make sure to add #define SSD1306OLED in config.h
+#ifdef SSD1306OLED
+
+// When add source files to SRC in rules.mk, you can use functions.
+const char *read_layer_state(void);
+const char *read_logo(void);
+void set_keylog(uint16_t keycode, keyrecord_t *record);
+const char *read_keylog(void);
+const char *read_keylogs(void);
+
+// const char *read_mode_icon(bool swap);
+// const char *read_host_led_state(void);
+// void set_timelog(void);
+// const char *read_timelog(void);
+
+void matrix_scan_user(void) {
+  iota_gfx_task();
+}
+
+void matrix_render_user(struct CharacterMatrix *matrix) {
+  if (is_master) {
+    // If you want to change the display of OLED, you need to change here
+    matrix_write_ln(matrix, read_layer_state());
+    matrix_write_ln(matrix, read_keylog());
+    matrix_write_ln(matrix, read_keylogs());
+    //matrix_write_ln(matrix, read_mode_icon(keymap_config.swap_lalt_lgui));
+    //matrix_write_ln(matrix, read_host_led_state());
+    //matrix_write_ln(matrix, read_timelog());
+  } else {
+    matrix_write(matrix, read_logo());
+  }
+}
+
+void matrix_update(struct CharacterMatrix *dest, const struct CharacterMatrix *source) {
+  if (memcmp(dest->display, source->display, sizeof(dest->display))) {
+    memcpy(dest->display, source->display, sizeof(dest->display));
+    dest->dirty = true;
+  }
+}
+
+void iota_gfx_task_user(void) {
+  struct CharacterMatrix matrix;
+  matrix_clear(&matrix);
+  matrix_render_user(&matrix);
+  matrix_update(&display, &matrix);
+}
+#endif//SSD1306OLED
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  if (record->event.pressed) {
+#ifdef SSD1306OLED
+    set_keylog(keycode, record);
+#endif
+    // set_timelog();
+  }
+
+  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);
+      } else {
+        layer_off(_LOWER);
+      }
+      return false;
+      break;
+    case RAISE:
+      if (record->event.pressed) {
+        layer_on(_RAISE);
+      } else {
+        layer_off(_RAISE);
+      }
+      return false;
+      break;
+  }
+  return true;
+}
diff --git a/keyboards/claw44/keymaps/yfuku/config.h b/keyboards/claw44/keymaps/yfuku/config.h
new file mode 100644
index 000000000..244ffa709
--- /dev/null
+++ b/keyboards/claw44/keymaps/yfuku/config.h
@@ -0,0 +1,36 @@
+/*
+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/>.
+*/
+
+#pragma once
+
+//#define USE_MATRIX_I2C
+
+/* Select hand configuration */
+
+#define MASTER_LEFT
+// #define MASTER_RIGHT
+// #define EE_HANDS
+
+#define SSD1306OLED
+
+#define USE_SERIAL_PD2
+
+#define TAPPING_TERM 180
+#define IGNORE_MOD_TAP_INTERRUPT
diff --git a/keyboards/claw44/keymaps/yfuku/keymap.c b/keyboards/claw44/keymaps/yfuku/keymap.c
new file mode 100644
index 000000000..77d459b92
--- /dev/null
+++ b/keyboards/claw44/keymaps/yfuku/keymap.c
@@ -0,0 +1,221 @@
+#include QMK_KEYBOARD_H
+#ifdef PROTOCOL_LUFA
+  #include "lufa.h"
+  #include "split_util.h"
+#endif
+#ifdef SSD1306OLED
+  #include "ssd1306.h"
+#endif
+
+extern keymap_config_t keymap_config;
+
+extern uint8_t is_master;
+
+// 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.
+enum custom_keycodes {
+  QWERTY = SAFE_RANGE,
+  LOWER,
+  RAISE
+};
+
+enum macro_keycodes {
+  KC_SAMPLEMACRO,
+};
+
+// common
+#define KC_ KC_TRNS
+#define KC_XXXX KC_NO
+#define KC_RST RESET
+#define KC_VD KC__VOLDOWN
+#define KC_VU KC__VOLUP
+
+// layer
+#define KC_L_SPC LT(_LOWER, KC_SPC)
+#define KC_R_ENT LT(_RAISE, KC_ENT)
+
+// shift_t
+#define KC_S_TAB LSFT_T(KC_TAB)
+#define KC_S_ESC LSFT_T(KC_ESC)
+#define KC_S_JA LSFT_T(KC_LANG1)
+#define KC_S_EN LSFT_T(KC_LANG2)
+
+// cmd_t
+#define KC_M_F LCMD_T(KC_F)
+#define KC_M_D LCMD_T(KC_D)
+#define KC_M_J LCMD_T(KC_J)
+#define KC_M_K LCMD_T(KC_K)
+
+// ctl_t
+#define KC_C_S LCTL_T(KC_S)
+#define KC_C_L LCTL_T(KC_L)
+#define KC_C_BS LCTL_T(KC_BSPC)
+
+// alt_t
+#define KC_A_D ALT_T(KC_D)
+#define KC_A_K ALT_T(KC_K)
+#define KC_A_Z ALT_T(KC_Z)
+#define KC_A_SL ALT_T(KC_SLSH)
+#define KC_A_DEL ALT_T(KC_DEL)
+
+// cmd+shift_t
+#define KC_MS_Q SCMD_T(KC_Q)
+#define KC_MS_A SCMD_T(KC_A)
+#define KC_MS_S SCMD_T(KC_S)
+#define KC_MS_SC SCMD_T(KC_SCLN)
+#define KC_MS_ESC SCMD_T(KC_ESC)
+
+//
+#define KC_MR RCMD(KC_R)
+#define KC_MF RCMD(KC_F)
+#define KC_MW RCMD(KC_W)
+#define KC_MX RCMD(KC_X)
+#define KC_MC RCMD(KC_C)
+#define KC_MV RCMD(KC_V)
+#define KC_MTAB RCMD(KC_TAB)
+#define KC_MSF RCMD(RSFT(KC_F))
+#define KC_MSR RCMD(RSFT(KC_R))
+#define KC_MST RCMD(RSFT(KC_T))
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+
+  // M_ = LCMD_T(
+  // A_ = ALT_T(
+  // C_ = LCTL_T(
+  // MS_ = SMD_T(
+  // R_ = LT(_RAISE
+  // L_ = LT(_LOWER
+
+  [_QWERTY] = LAYOUT_kc( \
+  //,----+----+----+----+----+----.     ,----+----+----+----+----+----.
+     ESC , Q  , W  , E  , R  , T  ,       Y  , U  , I  , O  , P  ,MINS,
+  //|----+----+----+----+----+----|     |----+----+----+----+----+----|
+    S_TAB, A  ,C_S , D  ,M_F , G  ,       H  ,M_J , K  ,C_L ,SCLN,S_ESC,
+  //|----+----+----+----+----+----+     |----+----+----+----+----+----|
+         , Z  , X  , C  , V  , B  ,       N  , M  ,COMM,DOT ,SLSH,    ,
+  //`----+----+----+----+----+----/     \----+----+----+----+----+----'
+             A_DEL,S_EN,L_SPC,C_BS,      C_BS,R_ENT,S_JA,A_DEL
+  //          `----+----+----+----'     `----+----+----+----'
+  ),
+
+  //   \ ^ ! & |  @ = + * % -
+  // ( # $ " ' ~  ← ↓ ↑ → ` )
+  //         { [  ] }
+
+  [_RAISE] = LAYOUT_kc( \
+  //,----+----+----+----+----+----.     ,----+----+----+----+----+----.
+         ,BSLS,CIRC,EXLM,AMPR,PIPE,      AT  ,EQL ,PLUS,ASTR,PERC,MINS,
+  //|----+----+----+----+----+----|     |----+----+----+----+----+----|
+     LPRN,HASH,DLR ,DQT ,QUOT,TILD,      LEFT,DOWN, UP ,RGHT,GRV ,RPRN,
+  //|----+----+----+----+----+----|     |----+----+----+----+----+----|
+        ,     ,    ,    ,LCBR,LBRC,      RBRC,RCBR,    ,    ,    ,    ,
+  //`----+----+----+----+----+----/     \----+----+----+----+----+----'
+                   ,    ,BSPC,    ,          ,    ,    ,RST
+  //          `----+----+----+----'     `----+----+----+----'
+  ),
+
+  [_LOWER] = LAYOUT_kc( \
+  //,----+----+----+----+----+----.     ,----+----+----+----+----+----.
+         ,    ,    ,MSF ,MSR ,MST ,          ,EQL ,PLUS,ASTR,PERC,MINS,
+  //|----+----+----+----+----+----|     |----+----+----+----+----+----|
+         , 1  , 2  , 3  , 4  , 5  ,       6  , 7  , 8  , 9  , 0  ,    ,
+  //|----+----+----+----+----+----|     |----+----+----+----+----+----|
+         ,    ,    ,    ,    ,    ,          ,    ,COMM,DOT ,SLSH,    ,
+  //`----+----+----+--+-+----+----/     \----+----+----+----+----+----'
+               RST ,    ,    ,    ,          ,DEL ,    ,
+  //          `----+----+----+----'     `----+----+----+----'
+  ),
+};
+
+void matrix_init_user(void) {
+  //SSD1306 OLED init, make sure to add #define SSD1306OLED in config.h
+  #ifdef SSD1306OLED
+    iota_gfx_init(!has_usb());   // turns on the display
+  #endif
+}
+
+//SSD1306 OLED update loop, make sure to add #define SSD1306OLED in config.h
+#ifdef SSD1306OLED
+
+// When add source files to SRC in rules.mk, you can use functions.
+const char *read_layer_state(void);
+const char *read_logo(void);
+void set_keylog(uint16_t keycode, keyrecord_t *record);
+const char *read_keylog(void);
+const char *read_keylogs(void);
+
+// const char *read_mode_icon(bool swap);
+// const char *read_host_led_state(void);
+// void set_timelog(void);
+// const char *read_timelog(void);
+
+void matrix_scan_user(void) {
+  iota_gfx_task();
+}
+
+void matrix_render_user(struct CharacterMatrix *matrix) {
+  if (is_master) {
+    // If you want to change the display of OLED, you need to change here
+    matrix_write_ln(matrix, read_layer_state());
+    matrix_write_ln(matrix, read_keylog());
+    matrix_write_ln(matrix, read_keylogs());
+    //matrix_write_ln(matrix, read_mode_icon(keymap_config.swap_lalt_lgui));
+    //matrix_write_ln(matrix, read_host_led_state());
+    //matrix_write_ln(matrix, read_timelog());
+  } else {
+    matrix_write(matrix, read_logo());
+  }
+}
+
+void matrix_update(struct CharacterMatrix *dest, const struct CharacterMatrix *source) {
+  if (memcmp(dest->display, source->display, sizeof(dest->display))) {
+    memcpy(dest->display, source->display, sizeof(dest->display));
+    dest->dirty = true;
+  }
+}
+
+void iota_gfx_task_user(void) {
+  struct CharacterMatrix matrix;
+  matrix_clear(&matrix);
+  matrix_render_user(&matrix);
+  matrix_update(&display, &matrix);
+}
+#endif//SSD1306OLED
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+  if (record->event.pressed) {
+#ifdef SSD1306OLED
+    set_keylog(keycode, record);
+#endif
+    // set_timelog();
+  }
+
+  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);
+      } else {
+        layer_off(_LOWER);
+      }
+      return false;
+      break;
+    case RAISE:
+      if (record->event.pressed) {
+        layer_on(_RAISE);
+      } else {
+        layer_off(_RAISE);
+      }
+      return false;
+      break;
+  }
+  return true;
+}
+
diff --git a/keyboards/claw44/lib/glcdfont.c b/keyboards/claw44/lib/glcdfont.c
new file mode 100644
index 000000000..91f53d9c2
--- /dev/null
+++ b/keyboards/claw44/lib/glcdfont.c
@@ -0,0 +1,243 @@
+// This is the 'classic' fixed-space bitmap font for Adafruit_GFX since 1.0.
+// See gfxfont.h for newer custom bitmap font info.
+
+#ifndef FONT5X7_H
+#define FONT5X7_H
+
+#ifdef __AVR__
+ #include <avr/io.h>
+ #include <avr/pgmspace.h>
+#elif defined(ESP8266)
+ #include <pgmspace.h>
+#else
+ #define PROGMEM
+#endif
+
+// Standard ASCII 5x7 font
+const unsigned char font[] PROGMEM = {
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x3E, 0x5B, 0x4F, 0x5B, 0x3E, 0x00,
+0x3E, 0x6B, 0x4F, 0x6B, 0x3E, 0x00,
+0x1C, 0x3E, 0x7C, 0x3E, 0x1C, 0x00,
+0x18, 0x3C, 0x7E, 0x3C, 0x18, 0x00,
+0x1C, 0x57, 0x7D, 0x57, 0x1C, 0x00,
+0x1C, 0x5E, 0x7F, 0x5E, 0x1C, 0x00,
+0x00, 0x18, 0x3C, 0x18, 0x00, 0x00,
+0xFF, 0xE7, 0xC3, 0xE7, 0xFF, 0x00,
+0x00, 0x18, 0x24, 0x18, 0x00, 0x00,
+0xFF, 0xE7, 0xDB, 0xE7, 0xFF, 0x00,
+0x30, 0x48, 0x3A, 0x06, 0x0E, 0x00,
+0x26, 0x29, 0x79, 0x29, 0x26, 0x00,
+0x40, 0x7F, 0x05, 0x05, 0x07, 0x00,
+0x40, 0x7F, 0x05, 0x25, 0x3F, 0x00,
+0x5A, 0x3C, 0xE7, 0x3C, 0x5A, 0x00,
+0x7F, 0x3E, 0x1C, 0x1C, 0x08, 0x00,
+0x08, 0x1C, 0x1C, 0x3E, 0x7F, 0x00,
+0x14, 0x22, 0x7F, 0x22, 0x14, 0x00,
+0x5F, 0x5F, 0x00, 0x5F, 0x5F, 0x00,
+0x06, 0x09, 0x7F, 0x01, 0x7F, 0x00,
+0x00, 0x66, 0x89, 0x95, 0x6A, 0x00,
+0x60, 0x60, 0x60, 0x60, 0x60, 0x00,
+0x94, 0xA2, 0xFF, 0xA2, 0x94, 0x00,
+0x08, 0x04, 0x7E, 0x04, 0x08, 0x00,
+0x10, 0x20, 0x7E, 0x20, 0x10, 0x00,
+0x08, 0x08, 0x2A, 0x1C, 0x08, 0x00,
+0x08, 0x1C, 0x2A, 0x08, 0x08, 0x00,
+0x1E, 0x10, 0x10, 0x10, 0x10, 0x00,
+0x0C, 0x1E, 0x0C, 0x1E, 0x0C, 0x00,
+0x30, 0x38, 0x3E, 0x38, 0x30, 0x00,
+0x06, 0x0E, 0x3E, 0x0E, 0x06, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x5F, 0x00, 0x00, 0x00,
+0x00, 0x07, 0x00, 0x07, 0x00, 0x00,
+0x14, 0x7F, 0x14, 0x7F, 0x14, 0x00,
+0x24, 0x2A, 0x7F, 0x2A, 0x12, 0x00,
+0x23, 0x13, 0x08, 0x64, 0x62, 0x00,
+0x36, 0x49, 0x56, 0x20, 0x50, 0x00,
+0x00, 0x08, 0x07, 0x03, 0x00, 0x00,
+0x00, 0x1C, 0x22, 0x41, 0x00, 0x00,
+0x00, 0x41, 0x22, 0x1C, 0x00, 0x00,
+0x2A, 0x1C, 0x7F, 0x1C, 0x2A, 0x00,
+0x08, 0x08, 0x3E, 0x08, 0x08, 0x00,
+0x00, 0x80, 0x70, 0x30, 0x00, 0x00,
+0x08, 0x08, 0x08, 0x08, 0x08, 0x00,
+0x00, 0x00, 0x60, 0x60, 0x00, 0x00,
+0x20, 0x10, 0x08, 0x04, 0x02, 0x00,
+0x3E, 0x51, 0x49, 0x45, 0x3E, 0x00,
+0x00, 0x42, 0x7F, 0x40, 0x00, 0x00,
+0x72, 0x49, 0x49, 0x49, 0x46, 0x00,
+0x21, 0x41, 0x49, 0x4D, 0x33, 0x00,
+0x18, 0x14, 0x12, 0x7F, 0x10, 0x00,
+0x27, 0x45, 0x45, 0x45, 0x39, 0x00,
+0x3C, 0x4A, 0x49, 0x49, 0x31, 0x00,
+0x41, 0x21, 0x11, 0x09, 0x07, 0x00,
+0x36, 0x49, 0x49, 0x49, 0x36, 0x00,
+0x46, 0x49, 0x49, 0x29, 0x1E, 0x00,
+0x00, 0x00, 0x14, 0x00, 0x00, 0x00,
+0x00, 0x40, 0x34, 0x00, 0x00, 0x00,
+0x00, 0x08, 0x14, 0x22, 0x41, 0x00,
+0x14, 0x14, 0x14, 0x14, 0x14, 0x00,
+0x00, 0x41, 0x22, 0x14, 0x08, 0x00,
+0x02, 0x01, 0x59, 0x09, 0x06, 0x00,
+0x3E, 0x41, 0x5D, 0x59, 0x4E, 0x00,
+0x7C, 0x12, 0x11, 0x12, 0x7C, 0x00,
+0x7F, 0x49, 0x49, 0x49, 0x36, 0x00,
+0x3E, 0x41, 0x41, 0x41, 0x22, 0x00,
+0x7F, 0x41, 0x41, 0x41, 0x3E, 0x00,
+0x7F, 0x49, 0x49, 0x49, 0x41, 0x00,
+0x7F, 0x09, 0x09, 0x09, 0x01, 0x00,
+0x3E, 0x41, 0x41, 0x51, 0x73, 0x00,
+0x7F, 0x08, 0x08, 0x08, 0x7F, 0x00,
+0x00, 0x41, 0x7F, 0x41, 0x00, 0x00,
+0x20, 0x40, 0x41, 0x3F, 0x01, 0x00,
+0x7F, 0x08, 0x14, 0x22, 0x41, 0x00,
+0x7F, 0x40, 0x40, 0x40, 0x40, 0x00,
+0x7F, 0x02, 0x1C, 0x02, 0x7F, 0x00,
+0x7F, 0x04, 0x08, 0x10, 0x7F, 0x00,
+0x3E, 0x41, 0x41, 0x41, 0x3E, 0x00,
+0x7F, 0x09, 0x09, 0x09, 0x06, 0x00,
+0x3E, 0x41, 0x51, 0x21, 0x5E, 0x00,
+0x7F, 0x09, 0x19, 0x29, 0x46, 0x00,
+0x26, 0x49, 0x49, 0x49, 0x32, 0x00,
+0x03, 0x01, 0x7F, 0x01, 0x03, 0x00,
+0x3F, 0x40, 0x40, 0x40, 0x3F, 0x00,
+0x1F, 0x20, 0x40, 0x20, 0x1F, 0x00,
+0x3F, 0x40, 0x38, 0x40, 0x3F, 0x00,
+0x63, 0x14, 0x08, 0x14, 0x63, 0x00,
+0x03, 0x04, 0x78, 0x04, 0x03, 0x00,
+0x61, 0x59, 0x49, 0x4D, 0x43, 0x00,
+0x00, 0x7F, 0x41, 0x41, 0x41, 0x00,
+0x02, 0x04, 0x08, 0x10, 0x20, 0x00,
+0x00, 0x41, 0x41, 0x41, 0x7F, 0x00,
+0x04, 0x02, 0x01, 0x02, 0x04, 0x00,
+0x40, 0x40, 0x40, 0x40, 0x40, 0x00,
+0x00, 0x03, 0x07, 0x08, 0x00, 0x00,
+0x20, 0x54, 0x54, 0x78, 0x40, 0x00,
+0x7F, 0x28, 0x44, 0x44, 0x38, 0x00,
+0x38, 0x44, 0x44, 0x44, 0x28, 0x00,
+0x38, 0x44, 0x44, 0x28, 0x7F, 0x00,
+0x38, 0x54, 0x54, 0x54, 0x18, 0x00,
+0x00, 0x08, 0x7E, 0x09, 0x02, 0x00,
+0x18, 0x24, 0x24, 0x1C, 0x78, 0x00,
+0x7F, 0x08, 0x04, 0x04, 0x78, 0x00,
+0x00, 0x44, 0x7D, 0x40, 0x00, 0x00,
+0x20, 0x40, 0x40, 0x3D, 0x00, 0x00,
+0x7F, 0x10, 0x28, 0x44, 0x00, 0x00,
+0x00, 0x41, 0x7F, 0x40, 0x00, 0x00,
+0x7C, 0x04, 0x78, 0x04, 0x78, 0x00,
+0x7C, 0x08, 0x04, 0x04, 0x78, 0x00,
+0x38, 0x44, 0x44, 0x44, 0x38, 0x00,
+0x7C, 0x18, 0x24, 0x24, 0x18, 0x00,
+0x18, 0x24, 0x24, 0x18, 0x7C, 0x00,
+0x7C, 0x08, 0x04, 0x04, 0x08, 0x00,
+0x48, 0x54, 0x54, 0x54, 0x24, 0x00,
+0x04, 0x04, 0x3F, 0x44, 0x24, 0x00,
+0x3C, 0x40, 0x40, 0x20, 0x7C, 0x00,
+0x1C, 0x20, 0x40, 0x20, 0x1C, 0x00,
+0x3C, 0x40, 0x30, 0x40, 0x3C, 0x00,
+0x44, 0x28, 0x10, 0x28, 0x44, 0x00,
+0x4C, 0x90, 0x90, 0x90, 0x7C, 0x00,
+0x44, 0x64, 0x54, 0x4C, 0x44, 0x00,
+0x00, 0x08, 0x36, 0x41, 0x00, 0x00,
+0x00, 0x00, 0x77, 0x00, 0x00, 0x00,
+0x00, 0x41, 0x36, 0x08, 0x00, 0x00,
+0x02, 0x01, 0x02, 0x04, 0x02, 0x00,
+0x3C, 0x26, 0x23, 0x26, 0x3C, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x80, 0x80, 0x80, 0x80, 0x80,
+  0x80, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0xFC, 0xFC, 0xFC, 0xFC, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x80,
+  0x80, 0x80, 0x80, 0x00, 0x00, 0x00,
+  0x00, 0x80, 0x80, 0x80, 0x80, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x80, 0x80,
+  0x80, 0x80, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x80, 0xC0, 0xF0, 0xF8, 0xF8,
+  0xF8, 0xF8, 0xF8, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x80,
+  0xE0, 0xF8, 0xF8, 0xF8, 0xF8, 0xF8,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0xE0, 0xF0, 0xF0, 0xF0, 0xE0, 0xEC,
+0xEE, 0xF7, 0xF3, 0x70, 0x20, 0x00,
+0x7C, 0x7C, 0x7C, 0x7E, 0x00, 0x7E,
+0x7E, 0x7E, 0x7F, 0x7F, 0x7F, 0x00,
+0x00, 0x80, 0xC0, 0xE0, 0x7E, 0x5B,
+0x4F, 0x5B, 0xFE, 0xC0, 0x00, 0x00,
+0xC0, 0x00, 0xDC, 0xD7, 0xDE, 0xDE,
+0xDE, 0xD7, 0xDC, 0x00, 0xC0, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0xF8, 0xFC, 0xFE,
+  0xFF, 0x1F, 0x07, 0x07, 0x07, 0x07,
+  0x1F, 0x1F, 0x1F, 0x1E, 0x18, 0x00,
+  0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0x00,
+  0x00, 0x00, 0x00, 0x9E, 0xDF, 0xDF,
+  0xCF, 0xC7, 0xE7, 0xE7, 0xE7, 0xFF,
+  0xFF, 0xFF, 0xFE, 0x00, 0x00, 0x03,
+  0x3F, 0xFF, 0xFF, 0xFE, 0xC0, 0x00,
+  0xF0, 0xFF, 0xFF, 0x1F, 0xFF, 0xFF,
+  0xF0, 0x00, 0xC0, 0xFC, 0xFF, 0xFF,
+  0x3F, 0x03, 0x00, 0xC0, 0xF0, 0xF8,
+  0xFE, 0x9F, 0x87, 0x83, 0x80, 0xFF,
+  0xFF, 0xFF, 0xFF, 0x80, 0x80, 0x00,
+  0x00, 0xE0, 0xF8, 0xFC, 0xBF, 0x8F,
+  0x83, 0x81, 0xFF, 0xFF, 0xFF, 0xFF,
+  0x80, 0x80, 0x80, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x0F, 0x1F, 0x3F, 0x7F, 0x7F, 0x7F,
+0x7F, 0x7F, 0x3F, 0x1E, 0x0C, 0x00,
+0x1F, 0x1F, 0x1F, 0x3F, 0x00, 0x3F,
+0x3F, 0x3F, 0x7F, 0x7F, 0x7F, 0x00,
+0x30, 0x7B, 0x7F, 0x78, 0x30, 0x20,
+0x20, 0x30, 0x78, 0x7F, 0x3B, 0x00,
+0x03, 0x00, 0x0F, 0x7F, 0x0F, 0x0F,
+0x0F, 0x7F, 0x0F, 0x00, 0x03, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x07, 0x1F, 0x3F,
+  0x7F, 0x7C, 0x78, 0x70, 0x70, 0x78,
+  0x7E, 0x3E, 0x3E, 0x0E, 0x06, 0x00,
+  0x00, 0x7F, 0x7F, 0x7F, 0x7F, 0x00,
+  0x00, 0x00, 0x1F, 0x3F, 0x7F, 0x7F,
+  0x79, 0x71, 0x70, 0x30, 0x38, 0x3F,
+  0x7F, 0x7F, 0x7F, 0x60, 0x00, 0x00,
+  0x00, 0x01, 0x1F, 0x7F, 0x7F, 0x7E,
+  0x7F, 0x1F, 0x01, 0x00, 0x01, 0x3F,
+  0x7F, 0x7E, 0x7F, 0x7F, 0x0F, 0x01,
+  0x00, 0x00, 0x00, 0x03, 0x03, 0x03,
+  0x03, 0x03, 0x03, 0x03, 0x03, 0x7F,
+  0x7F, 0x7F, 0x7F, 0x03, 0x03, 0x00,
+  0x00, 0x03, 0x03, 0x03, 0x03, 0x03,
+  0x03, 0x03, 0x7F, 0x7F, 0x7F, 0x7F,
+  0x07, 0x03, 0x03, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+};
+#endif // FONT5X7_H
diff --git a/keyboards/claw44/lib/host_led_state_reader.c b/keyboards/claw44/lib/host_led_state_reader.c
new file mode 100644
index 000000000..980823b31
--- /dev/null
+++ b/keyboards/claw44/lib/host_led_state_reader.c
@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include "claw44.h"
+
+char host_led_state_str[24];
+
+const char *read_host_led_state(void)
+{
+  uint8_t leds = host_keyboard_leds();
+  snprintf(host_led_state_str, sizeof(host_led_state_str), "NL:%s CL:%s SL:%s",
+           (leds & (1 << USB_LED_NUM_LOCK)) ? "on" : "- ",
+           (leds & (1 << USB_LED_CAPS_LOCK)) ? "on" : "- ",
+           (leds & (1 << USB_LED_SCROLL_LOCK)) ? "on" : "- ");
+
+  return host_led_state_str;
+}
diff --git a/keyboards/claw44/lib/keylogger.c b/keyboards/claw44/lib/keylogger.c
new file mode 100644
index 000000000..092b6929b
--- /dev/null
+++ b/keyboards/claw44/lib/keylogger.c
@@ -0,0 +1,45 @@
+#include <stdio.h>
+#include "claw44.h"
+
+char keylog_str[24] = {};
+char keylogs_str[21] = {};
+int keylogs_str_idx = 0;
+
+const char code_to_name[60] = {
+    ' ', ' ', ' ', ' ', 'a', 'b', 'c', 'd', 'e', 'f',
+    'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p',
+    'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
+    '1', '2', '3', '4', '5', '6', '7', '8', '9', '0',
+    'R', 'E', 'B', 'T', ' ', ' ', ' ', ' ', ' ', ' ',
+    ' ', ';', '\'', ' ', ',', '.', '/', ' ', ' ', ' '};
+
+void set_keylog(uint16_t keycode, keyrecord_t *record) {
+  char name = ' ';
+  if (keycode < 60) {
+    name = code_to_name[keycode];
+  }
+
+  // update keylog
+  snprintf(keylog_str, sizeof(keylog_str), "%dx%d, k%2d : %c",
+           record->event.key.row, record->event.key.col,
+           keycode, name);
+
+  // update keylogs
+  if (keylogs_str_idx == sizeof(keylogs_str) - 1) {
+    keylogs_str_idx = 0;
+    for (int i = 0; i < sizeof(keylogs_str) - 1; i++) {
+      keylogs_str[i] = ' ';
+    }
+  }
+
+  keylogs_str[keylogs_str_idx] = name;
+  keylogs_str_idx++;
+}
+
+const char *read_keylog(void) {
+  return keylog_str;
+}
+
+const char *read_keylogs(void) {
+  return keylogs_str;
+}
diff --git a/keyboards/claw44/lib/layer_state_reader.c b/keyboards/claw44/lib/layer_state_reader.c
new file mode 100644
index 000000000..d92b6df58
--- /dev/null
+++ b/keyboards/claw44/lib/layer_state_reader.c
@@ -0,0 +1,35 @@
+
+#include QMK_KEYBOARD_H
+#include <stdio.h>
+#include "claw44.h"
+
+#define L_BASE 0
+#define L_LOWER (1<<_LOWER)
+#define L_RAISE (1<<_RAISE)
+#define L_ADJUST (1<<_ADJUST)
+#define L_ADJUST_TRI (L_ADJUST|L_RAISE|L_LOWER)
+
+char layer_state_str[24];
+
+const char *read_layer_state(void) {
+  switch (layer_state)
+  {
+  case L_BASE:
+    snprintf(layer_state_str, sizeof(layer_state_str), "Layer: Default");
+    break;
+  case L_RAISE:
+    snprintf(layer_state_str, sizeof(layer_state_str), "Layer: Raise");
+    break;
+  case L_LOWER:
+    snprintf(layer_state_str, sizeof(layer_state_str), "Layer: Lower");
+    break;
+  case L_ADJUST:
+  case L_ADJUST_TRI:
+    snprintf(layer_state_str, sizeof(layer_state_str), "Layer: Adjust");
+    break;
+  default:
+    snprintf(layer_state_str, sizeof(layer_state_str), "Layer: Undef-%ld", layer_state);
+  }
+
+  return layer_state_str;
+}
diff --git a/keyboards/claw44/lib/logo_reader.c b/keyboards/claw44/lib/logo_reader.c
new file mode 100644
index 000000000..b5b437b2b
--- /dev/null
+++ b/keyboards/claw44/lib/logo_reader.c
@@ -0,0 +1,11 @@
+#include "claw44.h"
+
+const char *read_logo(void) {
+  static char logo[] = {
+      0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94,
+      0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 0xb0, 0xb1, 0xb2, 0xb3, 0xb4,
+      0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4,
+      0};
+
+  return logo;
+}
diff --git a/keyboards/claw44/lib/mode_icon_reader.c b/keyboards/claw44/lib/mode_icon_reader.c
new file mode 100644
index 000000000..a9272bb9a
--- /dev/null
+++ b/keyboards/claw44/lib/mode_icon_reader.c
@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include "claw44.h"
+
+char mode_icon[24];
+
+const char *read_mode_icon(bool swap) {
+  static char logo[][2][3] = {{{0x95, 0x96, 0}, {0xb5, 0xb6, 0}}, {{0x97, 0x98, 0}, {0xb7, 0xb8, 0}}};
+  if (swap == false) {
+    snprintf(mode_icon, sizeof(mode_icon), "%s\n%s", logo[0][0], logo[0][1]);
+  } else {
+    snprintf(mode_icon, sizeof(mode_icon), "%s\n%s", logo[1][0], logo[1][1]);
+  }
+
+  return mode_icon;
+}
diff --git a/keyboards/claw44/lib/rgb_state_reader.c b/keyboards/claw44/lib/rgb_state_reader.c
new file mode 100644
index 000000000..e0efe2e52
--- /dev/null
+++ b/keyboards/claw44/lib/rgb_state_reader.c
@@ -0,0 +1,15 @@
+#ifdef RGBLIGHT_ENABLE
+
+#include QMK_KEYBOARD_H
+#include <stdio.h>
+
+extern rgblight_config_t rgblight_config;
+char rbf_info_str[24];
+const char *read_rgb_info(void) {
+
+  snprintf(rbf_info_str, sizeof(rbf_info_str), "%s %2d h%3d s%3d v%3d",
+    rgblight_config.enable ? "on" : "- ", rgblight_config.mode,
+    rgblight_config.hue, rgblight_config.sat, rgblight_config.val);
+  return rbf_info_str;
+}
+#endif
diff --git a/keyboards/claw44/lib/timelogger.c b/keyboards/claw44/lib/timelogger.c
new file mode 100644
index 000000000..ecd4ed3ea
--- /dev/null
+++ b/keyboards/claw44/lib/timelogger.c
@@ -0,0 +1,16 @@
+#include <stdio.h>
+#include "claw44.h"
+
+char timelog_str[24] = {};
+int last_time = 0;
+int elapsed_time = 0;
+
+void set_timelog(void) {
+  elapsed_time = timer_elapsed(last_time);
+  last_time = timer_read();
+  snprintf(timelog_str, sizeof(timelog_str), "lt:%5d, et:%5d", last_time, elapsed_time);
+}
+
+const char *read_timelog(void) {
+  return timelog_str;
+}
diff --git a/keyboards/claw44/readme.md b/keyboards/claw44/readme.md
new file mode 100644
index 000000000..7e72e0897
--- /dev/null
+++ b/keyboards/claw44/readme.md
@@ -0,0 +1,15 @@
+# Claw44
+
+![Claw44](https://i.imgur.com/5a8iogl.jpg)
+
+A split keyboard with 3x6 vertically staggered keys and 4 thumb keys.
+
+Keyboard Maintainer: [@yfuku_](https://twitter.com/yfuku_)  
+Hardware Supported: Claw44 PCB, ProMicro  
+Hardware Availability: https://yfuku.booth.pm/  
+
+Make example for this keyboard (after setting up your build environment):
+
+    make claw44:default
+
+See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
diff --git a/keyboards/claw44/rev1/config.h b/keyboards/claw44/rev1/config.h
new file mode 100644
index 000000000..ba2ed4559
--- /dev/null
+++ b/keyboards/claw44/rev1/config.h
@@ -0,0 +1,76 @@
+/*
+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/>.
+*/
+
+#pragma once
+
+/* USB Device descriptor parameter */
+#define VENDOR_ID       0xFEED
+#define PRODUCT_ID      0x3060
+#define DEVICE_VER      0x0001
+#define MANUFACTURER    yfuku
+#define PRODUCT         claw44
+#define DESCRIPTION     A split keyboard with 3x6 vertically staggered keys and 4 thumb keys
+
+/* key matrix size */
+// Rows are doubled-up
+#define MATRIX_ROWS 8
+#define MATRIX_COLS 7
+#define MATRIX_ROW_PINS { D4, C6, D7, E6 }
+
+// wiring of each half
+#define MATRIX_COL_PINS { F4, F5, F6, F7, B1, B3, B2 }
+// #define MATRIX_COL_PINS { B2, B3, B1, F7, F6, F5, F4 } //uncomment this line and comment line above if you need to reverse left-to-right key order
+
+/* 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
+
+/* ws2812 RGB LED */
+/*
+#define RGB_DI_PIN D3
+
+#define RGBLED_NUM 12    // Number of LEDs
+*/
+
+/*
+ * 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
diff --git a/keyboards/claw44/rev1/matrix.c b/keyboards/claw44/rev1/matrix.c
new file mode 100644
index 000000000..718cc5744
--- /dev/null
+++ b/keyboards/claw44/rev1/matrix.c
@@ -0,0 +1,357 @@
+/*
+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 <string.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"
+
+#ifdef USE_MATRIX_I2C
+#  include "i2c.h"
+#else // USE_SERIAL
+#  include "split_scomm.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;
+uint8_t is_master = 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);
+static uint8_t matrix_master_scan(void);
+
+
+__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;
+    TXLED0;
+    RXLED0;
+
+    // initialize matrix state: all keys off
+    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
+        matrix[i] = 0;
+        matrix_debouncing[i] = 0;
+    }
+
+    is_master = has_usb();
+
+    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_MATRIX_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(int master_changed) {
+    int slaveOffset = (isLeftHand) ? (ROWS_PER_HAND) : 0;
+#ifdef SERIAL_USE_MULTI_TRANSACTION
+    int ret=serial_update_buffers(master_changed);
+#else
+    int ret=serial_update_buffers();
+#endif
+    if (ret ) {
+        if(ret==2) RXLED1;
+        return 1;
+    }
+    RXLED0;
+    memcpy(&matrix[slaveOffset],
+        (void *)serial_slave_buffer, SERIAL_SLAVE_BUFFER_LENGTH);
+    return 0;
+}
+#endif
+
+uint8_t matrix_scan(void)
+{
+    if (is_master) {
+        matrix_master_scan();
+    }else{
+        matrix_slave_scan();
+        int offset = (isLeftHand) ? ROWS_PER_HAND : 0;
+        memcpy(&matrix[offset],
+               (void *)serial_master_buffer, SERIAL_MASTER_BUFFER_LENGTH);
+        matrix_scan_quantum();
+    }
+    return 1;
+}
+
+
+uint8_t matrix_master_scan(void) {
+
+    int ret = _matrix_scan();
+    int mchanged = 1;
+
+    int offset = (isLeftHand) ? 0 : ROWS_PER_HAND;
+
+#ifdef USE_MATRIX_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
+  #ifdef SERIAL_USE_MULTI_TRANSACTION
+    mchanged = memcmp((void *)serial_master_buffer,
+		      &matrix[offset], SERIAL_MASTER_BUFFER_LENGTH);
+  #endif
+    memcpy((void *)serial_master_buffer,
+	   &matrix[offset], SERIAL_MASTER_BUFFER_LENGTH);
+#endif
+
+#ifdef USE_MATRIX_I2C
+    if( i2c_transaction() ) {
+#else // USE_SERIAL
+    if( serial_transaction(mchanged) ) {
+#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_MATRIX_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
+  #ifdef SERIAL_USE_MULTI_TRANSACTION
+    int change = 0;
+  #endif
+    for (int i = 0; i < ROWS_PER_HAND; ++i) {
+  #ifdef SERIAL_USE_MULTI_TRANSACTION
+        if( serial_slave_buffer[i] != matrix[offset+i] )
+	    change = 1;
+  #endif
+        serial_slave_buffer[i] = matrix[offset+i];
+    }
+  #ifdef SERIAL_USE_MULTI_TRANSACTION
+    slave_buffer_change_count += change;
+  #endif
+#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/claw44/rev1/rev1.c b/keyboards/claw44/rev1/rev1.c
new file mode 100644
index 000000000..9529636f5
--- /dev/null
+++ b/keyboards/claw44/rev1/rev1.c
@@ -0,0 +1,8 @@
+#include "claw44.h"
+
+#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
diff --git a/keyboards/claw44/rev1/rev1.h b/keyboards/claw44/rev1/rev1.h
new file mode 100644
index 000000000..f7ec2cbfe
--- /dev/null
+++ b/keyboards/claw44/rev1/rev1.h
@@ -0,0 +1,57 @@
+#pragma once
+
+#include "../claw44.h"
+
+//void promicro_bootloader_jmp(bool program);
+#include "quantum.h"
+
+#ifdef RGBLIGHT_ENABLE
+//rgb led driver
+#include "ws2812.h"
+#endif
+
+#ifdef USE_I2C
+#include <stddef.h>
+#ifdef __AVR__
+	#include <avr/io.h>
+	#include <avr/interrupt.h>
+#endif
+#endif
+
+//void promicro_bootloader_jmp(bool program);
+#define LAYOUT( \
+  L00, L01, L02, L03, L04, L05,           R00, R01, R02, R03, R04, R05, \
+  L10, L11, L12, L13, L14, L15,           R10, R11, R12, R13, R14, R15, \
+  L20, L21, L22, L23, L24, L25,           R20, R21, R22, R23, R24, R25, \
+                 L30, L31, L32, L33, R30, R31, R32, R33 \
+  ) \
+  { \
+    { L00, L01, L02, L03, L04, L05 }, \
+    { L10, L11, L12, L13, L14, L15 }, \
+    { L20, L21, L22, L23, L24, L25 }, \
+    { KC_NO, KC_NO, L30, L31, L32, L33 }, \
+    { R05, R04, R03, R02, R01, R00 }, \
+    { R15, R14, R13, R12, R11, R10 }, \
+    { R25, R24, R23, R22, R21, R20 }, \
+    { KC_NO, KC_NO, R33, R32, R31, R30 } \
+  }
+
+#define LAYOUT_kc( \
+  L00, L01, L02, L03, L04, L05,           R00, R01, R02, R03, R04, R05, \
+  L10, L11, L12, L13, L14, L15,           R10, R11, R12, R13, R14, R15, \
+  L20, L21, L22, L23, L24, L25,           R20, R21, R22, R23, R24, R25, \
+                 L30, L31, L32, L33, R30, R31, R32, R33 \
+  ) \
+  LAYOUT( \
+    KC_##L00, KC_##L01, KC_##L02, KC_##L03, KC_##L04, KC_##L05,                     KC_##R00, KC_##R01, KC_##R02, KC_##R03, KC_##R04, KC_##R05, \
+    KC_##L10, KC_##L11, KC_##L12, KC_##L13, KC_##L14, KC_##L15,                     KC_##R10, KC_##R11, KC_##R12, KC_##R13, KC_##R14, KC_##R15, \
+    KC_##L20, KC_##L21, KC_##L22, KC_##L23, KC_##L24, KC_##L25,                     KC_##R20, KC_##R21, KC_##R22, KC_##R23, KC_##R24, KC_##R25, \
+                                  KC_##L30, KC_##L31, KC_##L32, KC_##L33, KC_##R30, KC_##R31, KC_##R32, KC_##R33 \
+  )
+
+enum layer_number {
+  _QWERTY = 0,
+  _LOWER,
+  _RAISE,
+  _ADJUST,
+};
diff --git a/keyboards/claw44/rev1/rules.mk b/keyboards/claw44/rev1/rules.mk
new file mode 100644
index 000000000..ae95ec401
--- /dev/null
+++ b/keyboards/claw44/rev1/rules.mk
@@ -0,0 +1,31 @@
+SRC += rev1/matrix.c
+SRC += rev1/split_util.c
+SRC += rev1/split_scomm.c
+
+# Build Options
+BOOTMAGIC_ENABLE = no       # Virtual DIP switch configuration(+1000)
+MOUSEKEY_ENABLE = no        # Mouse keys(+4700)
+EXTRAKEY_ENABLE = no        # Audio control and System control(+450)
+CONSOLE_ENABLE = no         # Console for debug(+400)
+COMMAND_ENABLE = no         # 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.
+SWAP_HANDS_ENABLE = no      # Enable one-hand typing
+
+# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
+
+# If you want to change the display of OLED, you need to change here
+SRC += ./lib/glcdfont.c \
+       ./lib/layer_state_reader.c \
+       ./lib/logo_reader.c \
+       ./lib/keylogger.c \
+       # ./lib/rgb_state_reader.c \
+       # ./lib/mode_icon_reader.c \
+       # ./lib/host_led_state_reader.c \
+       # ./lib/timelogger.c \
diff --git a/keyboards/claw44/rev1/serial_config.h b/keyboards/claw44/rev1/serial_config.h
new file mode 100644
index 000000000..4fab8e8dd
--- /dev/null
+++ b/keyboards/claw44/rev1/serial_config.h
@@ -0,0 +1,4 @@
+#ifndef SOFT_SERIAL_PIN
+#define SOFT_SERIAL_PIN D2
+#define SERIAL_USE_MULTI_TRANSACTION
+#endif
diff --git a/keyboards/claw44/rev1/split_scomm.c b/keyboards/claw44/rev1/split_scomm.c
new file mode 100644
index 000000000..a1fe6ba5b
--- /dev/null
+++ b/keyboards/claw44/rev1/split_scomm.c
@@ -0,0 +1,91 @@
+#ifdef USE_SERIAL
+#ifdef SERIAL_USE_MULTI_TRANSACTION
+/* --- USE flexible API (using multi-type transaction function) --- */
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <split_scomm.h>
+#include "serial.h"
+#ifdef CONSOLE_ENABLE
+  #include <print.h>
+#endif
+
+uint8_t volatile serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH] = {0};
+uint8_t volatile serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH] = {0};
+uint8_t volatile status_com = 0;
+uint8_t volatile status1 = 0;
+uint8_t slave_buffer_change_count = 0;
+uint8_t s_change_old = 0xff;
+uint8_t s_change_new = 0xff;
+
+SSTD_t transactions[] = {
+#define GET_SLAVE_STATUS 0
+    /* master buffer not changed, only recive slave_buffer_change_count */
+    { (uint8_t *)&status_com,
+      0, NULL,
+      sizeof(slave_buffer_change_count), &slave_buffer_change_count,
+    },
+#define PUT_MASTER_GET_SLAVE_STATUS 1
+    /* master buffer changed need send, and recive slave_buffer_change_count  */
+    { (uint8_t *)&status_com,
+      sizeof(serial_master_buffer), (uint8_t *)serial_master_buffer,
+      sizeof(slave_buffer_change_count), &slave_buffer_change_count,
+    },
+#define GET_SLAVE_BUFFER 2
+    /* recive serial_slave_buffer */
+    { (uint8_t *)&status1,
+      0, NULL,
+      sizeof(serial_slave_buffer), (uint8_t *)serial_slave_buffer
+    }
+};
+
+void serial_master_init(void)
+{
+    soft_serial_initiator_init(transactions, TID_LIMIT(transactions));
+}
+
+void serial_slave_init(void)
+{
+    soft_serial_target_init(transactions, TID_LIMIT(transactions));
+}
+
+// 0 => no error
+// 1 => slave did not respond
+// 2 => checksum error
+int serial_update_buffers(int master_update)
+{
+    int status, smatstatus;
+    static int need_retry = 0;
+
+    if( s_change_old != s_change_new ) {
+        smatstatus = soft_serial_transaction(GET_SLAVE_BUFFER);
+        if( smatstatus == TRANSACTION_END ) {
+            s_change_old = s_change_new;
+#ifdef CONSOLE_ENABLE
+            uprintf("slave matrix = %b %b %b %b\n",
+                    serial_slave_buffer[0], serial_slave_buffer[1],
+                    serial_slave_buffer[2], serial_slave_buffer[3]);
+#endif
+        }
+    } else {
+        // serial_slave_buffer dosen't change
+        smatstatus = TRANSACTION_END; // dummy status
+    }
+
+    if( !master_update && !need_retry) {
+        status = soft_serial_transaction(GET_SLAVE_STATUS);
+    } else {
+        status = soft_serial_transaction(PUT_MASTER_GET_SLAVE_STATUS);
+    }
+    if( status == TRANSACTION_END ) {
+        s_change_new = slave_buffer_change_count;
+        need_retry = 0;
+    } else {
+        need_retry = 1;
+    }
+    return smatstatus;
+}
+
+#endif // SERIAL_USE_MULTI_TRANSACTION
+#endif /* USE_SERIAL */
diff --git a/keyboards/claw44/rev1/split_scomm.h b/keyboards/claw44/rev1/split_scomm.h
new file mode 100644
index 000000000..873d8939d
--- /dev/null
+++ b/keyboards/claw44/rev1/split_scomm.h
@@ -0,0 +1,24 @@
+#ifndef SPLIT_COMM_H
+#define SPLIT_COMM_H
+
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+/* --- USE Simple API (OLD API, compatible with let's split serial.c) --- */
+#include "serial.h"
+
+#else
+/* --- USE flexible API (using multi-type transaction function) --- */
+// Buffers for master - slave communication
+#define SERIAL_SLAVE_BUFFER_LENGTH MATRIX_ROWS/2
+#define SERIAL_MASTER_BUFFER_LENGTH MATRIX_ROWS/2
+
+extern volatile uint8_t serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH];
+extern volatile uint8_t serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH];
+extern uint8_t slave_buffer_change_count;
+
+void serial_master_init(void);
+void serial_slave_init(void);
+int serial_update_buffers(int master_changed);
+
+#endif
+
+#endif /* SPLIT_COMM_H */
diff --git a/keyboards/claw44/rev1/split_util.c b/keyboards/claw44/rev1/split_util.c
new file mode 100644
index 000000000..e1ff8b437
--- /dev/null
+++ b/keyboards/claw44/rev1/split_util.c
@@ -0,0 +1,70 @@
+#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"
+
+#ifdef USE_MATRIX_I2C
+#  include "i2c.h"
+#else
+#  include "split_scomm.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_MATRIX_I2C
+    i2c_master_init();
+#else
+    serial_master_init();
+#endif
+}
+
+static void keyboard_slave_setup(void) {
+
+#ifdef USE_MATRIX_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();
+}
+
+// this code runs before the usb and keyboard is initialized
+void matrix_setup(void) {
+    split_keyboard_setup();
+}
diff --git a/keyboards/claw44/rev1/split_util.h b/keyboards/claw44/rev1/split_util.h
new file mode 100644
index 000000000..687ca19bd
--- /dev/null
+++ b/keyboards/claw44/rev1/split_util.h
@@ -0,0 +1,19 @@
+#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 matrix_master_OLED_init (void);
+
+#endif
diff --git a/keyboards/claw44/rules.mk b/keyboards/claw44/rules.mk
new file mode 100644
index 000000000..907a5c832
--- /dev/null
+++ b/keyboards/claw44/rules.mk
@@ -0,0 +1,74 @@
+SRC += i2c.c
+SRC += serial.c
+SRC += ssd1306.c
+
+# if firmware size over limit, try this option
+# CFLAGS += -flto
+
+# 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 = no       # Mouse keys(+4700)
+EXTRAKEY_ENABLE = no       # Audio control and System control(+450)
+CONSOLE_ENABLE = no         # Console for debug(+400)
+COMMAND_ENABLE = no        # 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 SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE = no    # Breathing sleep LED during USB suspend
+
+CUSTOM_MATRIX = yes
+
+DEFAULT_FOLDER = claw44/rev1
diff --git a/keyboards/claw44/serial.c b/keyboards/claw44/serial.c
new file mode 100644
index 000000000..325c29a3f
--- /dev/null
+++ b/keyboards/claw44/serial.c
@@ -0,0 +1,590 @@
+/*
+ * WARNING: be careful changing this code, it is very timing dependent
+ *
+ * 2018-10-28 checked
+ *  avr-gcc 4.9.2
+ *  avr-gcc 5.4.0
+ *  avr-gcc 7.3.0
+ */
+
+#ifndef F_CPU
+#define F_CPU 16000000
+#endif
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <util/delay.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include "serial.h"
+//#include <pro_micro.h>
+
+#ifdef SOFT_SERIAL_PIN
+
+#ifdef __AVR_ATmega32U4__
+  // if using ATmega32U4 I2C, can not use PD0 and PD1 in soft serial.
+  #ifdef USE_I2C
+    #if SOFT_SERIAL_PIN == D0 || SOFT_SERIAL_PIN == D1
+      #error Using ATmega32U4 I2C, so can not use PD0, PD1
+    #endif
+  #endif
+
+  #if SOFT_SERIAL_PIN >= D0 && SOFT_SERIAL_PIN <= D3
+    #define SERIAL_PIN_DDR   DDRD
+    #define SERIAL_PIN_PORT  PORTD
+    #define SERIAL_PIN_INPUT PIND
+    #if SOFT_SERIAL_PIN == D0
+      #define SERIAL_PIN_MASK _BV(PD0)
+      #define EIMSK_BIT       _BV(INT0)
+      #define EICRx_BIT       (~(_BV(ISC00) | _BV(ISC01)))
+      #define SERIAL_PIN_INTERRUPT INT0_vect
+    #elif  SOFT_SERIAL_PIN == D1
+      #define SERIAL_PIN_MASK _BV(PD1)
+      #define EIMSK_BIT       _BV(INT1)
+      #define EICRx_BIT       (~(_BV(ISC10) | _BV(ISC11)))
+      #define SERIAL_PIN_INTERRUPT INT1_vect
+    #elif  SOFT_SERIAL_PIN == D2
+      #define SERIAL_PIN_MASK _BV(PD2)
+      #define EIMSK_BIT       _BV(INT2)
+      #define EICRx_BIT       (~(_BV(ISC20) | _BV(ISC21)))
+      #define SERIAL_PIN_INTERRUPT INT2_vect
+    #elif  SOFT_SERIAL_PIN == D3
+      #define SERIAL_PIN_MASK _BV(PD3)
+      #define EIMSK_BIT       _BV(INT3)
+      #define EICRx_BIT       (~(_BV(ISC30) | _BV(ISC31)))
+      #define SERIAL_PIN_INTERRUPT INT3_vect
+    #endif
+  #elif  SOFT_SERIAL_PIN == E6
+    #define SERIAL_PIN_DDR   DDRE
+    #define SERIAL_PIN_PORT  PORTE
+    #define SERIAL_PIN_INPUT PINE
+    #define SERIAL_PIN_MASK  _BV(PE6)
+    #define EIMSK_BIT        _BV(INT6)
+    #define EICRx_BIT        (~(_BV(ISC60) | _BV(ISC61)))
+    #define SERIAL_PIN_INTERRUPT INT6_vect
+  #else
+  #error invalid SOFT_SERIAL_PIN value
+  #endif
+
+#else
+ #error serial.c now support ATmega32U4 only
+#endif
+
+//////////////// for backward compatibility ////////////////////////////////
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+/* --- USE Simple API (OLD API, compatible with let's split serial.c) */
+  #if SERIAL_SLAVE_BUFFER_LENGTH > 0
+  uint8_t volatile serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH] = {0};
+  #endif
+  #if SERIAL_MASTER_BUFFER_LENGTH > 0
+  uint8_t volatile serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH] = {0};
+  #endif
+  uint8_t volatile status0 = 0;
+
+SSTD_t transactions[] = {
+    { (uint8_t *)&status0,
+  #if SERIAL_MASTER_BUFFER_LENGTH > 0
+      sizeof(serial_master_buffer), (uint8_t *)serial_master_buffer,
+  #else
+      0, (uint8_t *)NULL,
+  #endif
+  #if SERIAL_SLAVE_BUFFER_LENGTH > 0
+      sizeof(serial_slave_buffer), (uint8_t *)serial_slave_buffer
+  #else
+      0, (uint8_t *)NULL,
+  #endif
+  }
+};
+
+void serial_master_init(void)
+{ soft_serial_initiator_init(transactions, TID_LIMIT(transactions)); }
+
+void serial_slave_init(void)
+{ soft_serial_target_init(transactions, TID_LIMIT(transactions)); }
+
+// 0 => no error
+// 1 => slave did not respond
+// 2 => checksum error
+int serial_update_buffers()
+{
+    int result;
+    result = soft_serial_transaction();
+    return result;
+}
+
+#endif // end of Simple API (OLD API, compatible with let's split serial.c)
+////////////////////////////////////////////////////////////////////////////
+
+#define ALWAYS_INLINE __attribute__((always_inline))
+#define NO_INLINE __attribute__((noinline))
+#define _delay_sub_us(x)    __builtin_avr_delay_cycles(x)
+
+// parity check
+#define ODD_PARITY 1
+#define EVEN_PARITY 0
+#define PARITY EVEN_PARITY
+
+#ifdef SERIAL_DELAY
+  // custom setup in config.h
+  // #define TID_SEND_ADJUST 2
+  // #define SERIAL_DELAY 6             // micro sec
+  // #define READ_WRITE_START_ADJUST 30 // cycles
+  // #define READ_WRITE_WIDTH_ADJUST 8 // cycles
+#else
+// ============ Standard setups ============
+
+#ifndef SELECT_SOFT_SERIAL_SPEED
+#define SELECT_SOFT_SERIAL_SPEED 1
+//  0: about 189kbps
+//  1: about 137kbps (default)
+//  2: about 75kbps
+//  3: about 39kbps
+//  4: about 26kbps
+//  5: about 20kbps
+#endif
+
+#if __GNUC__ < 6
+  #define TID_SEND_ADJUST 14
+#else
+  #define TID_SEND_ADJUST 2
+#endif
+
+#if SELECT_SOFT_SERIAL_SPEED == 0
+  // Very High speed
+  #define SERIAL_DELAY 4             // micro sec
+  #if __GNUC__ < 6
+    #define READ_WRITE_START_ADJUST 33 // cycles
+    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
+  #else
+    #define READ_WRITE_START_ADJUST 34 // cycles
+    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
+  #endif
+#elif SELECT_SOFT_SERIAL_SPEED == 1
+  // High speed
+  #define SERIAL_DELAY 6             // micro sec
+  #if __GNUC__ < 6
+    #define READ_WRITE_START_ADJUST 30 // cycles
+    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
+  #else
+    #define READ_WRITE_START_ADJUST 33 // cycles
+    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
+  #endif
+#elif SELECT_SOFT_SERIAL_SPEED == 2
+  // Middle speed
+  #define SERIAL_DELAY 12            // micro sec
+  #define READ_WRITE_START_ADJUST 30 // cycles
+  #if __GNUC__ < 6
+    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
+  #else
+    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
+  #endif
+#elif SELECT_SOFT_SERIAL_SPEED == 3
+  // Low speed
+  #define SERIAL_DELAY 24            // micro sec
+  #define READ_WRITE_START_ADJUST 30 // cycles
+  #if __GNUC__ < 6
+    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
+  #else
+    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
+  #endif
+#elif SELECT_SOFT_SERIAL_SPEED == 4
+  // Very Low speed
+  #define SERIAL_DELAY 36            // micro sec
+  #define READ_WRITE_START_ADJUST 30 // cycles
+  #if __GNUC__ < 6
+    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
+  #else
+    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
+  #endif
+#elif SELECT_SOFT_SERIAL_SPEED == 5
+  // Ultra Low speed
+  #define SERIAL_DELAY 48            // micro sec
+  #define READ_WRITE_START_ADJUST 30 // cycles
+  #if __GNUC__ < 6
+    #define READ_WRITE_WIDTH_ADJUST 3 // cycles
+  #else
+    #define READ_WRITE_WIDTH_ADJUST 7 // cycles
+  #endif
+#else
+#error invalid SELECT_SOFT_SERIAL_SPEED value
+#endif /* SELECT_SOFT_SERIAL_SPEED */
+#endif /* SERIAL_DELAY */
+
+#define SERIAL_DELAY_HALF1 (SERIAL_DELAY/2)
+#define SERIAL_DELAY_HALF2 (SERIAL_DELAY - SERIAL_DELAY/2)
+
+#define SLAVE_INT_WIDTH_US 1
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+  #define SLAVE_INT_RESPONSE_TIME SERIAL_DELAY
+#else
+  #define SLAVE_INT_ACK_WIDTH_UNIT 2
+  #define SLAVE_INT_ACK_WIDTH 4
+#endif
+
+static SSTD_t *Transaction_table = NULL;
+static uint8_t Transaction_table_size = 0;
+
+inline static void serial_delay(void) ALWAYS_INLINE;
+inline static
+void serial_delay(void) {
+  _delay_us(SERIAL_DELAY);
+}
+
+inline static void serial_delay_half1(void) ALWAYS_INLINE;
+inline static
+void serial_delay_half1(void) {
+  _delay_us(SERIAL_DELAY_HALF1);
+}
+
+inline static void serial_delay_half2(void) ALWAYS_INLINE;
+inline static
+void serial_delay_half2(void) {
+  _delay_us(SERIAL_DELAY_HALF2);
+}
+
+inline static void serial_output(void) ALWAYS_INLINE;
+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_with_pullup(void) ALWAYS_INLINE;
+inline static
+void serial_input_with_pullup(void) {
+  SERIAL_PIN_DDR  &= ~SERIAL_PIN_MASK;
+  SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
+}
+
+inline static uint8_t serial_read_pin(void) ALWAYS_INLINE;
+inline static
+uint8_t serial_read_pin(void) {
+  return !!(SERIAL_PIN_INPUT & SERIAL_PIN_MASK);
+}
+
+inline static void serial_low(void) ALWAYS_INLINE;
+inline static
+void serial_low(void) {
+  SERIAL_PIN_PORT &= ~SERIAL_PIN_MASK;
+}
+
+inline static void serial_high(void) ALWAYS_INLINE;
+inline static
+void serial_high(void) {
+  SERIAL_PIN_PORT |= SERIAL_PIN_MASK;
+}
+
+void soft_serial_initiator_init(SSTD_t *sstd_table, int sstd_table_size)
+{
+    Transaction_table = sstd_table;
+    Transaction_table_size = (uint8_t)sstd_table_size;
+    serial_output();
+    serial_high();
+}
+
+void soft_serial_target_init(SSTD_t *sstd_table, int sstd_table_size)
+{
+    Transaction_table = sstd_table;
+    Transaction_table_size = (uint8_t)sstd_table_size;
+    serial_input_with_pullup();
+
+    // Enable INT0-INT3,INT6
+    EIMSK |= EIMSK_BIT;
+#if SERIAL_PIN_MASK == _BV(PE6)
+    // Trigger on falling edge of INT6
+    EICRB &= EICRx_BIT;
+#else
+    // Trigger on falling edge of INT0-INT3
+    EICRA &= EICRx_BIT;
+#endif
+}
+
+// Used by the sender to synchronize timing with the reciver.
+static void sync_recv(void) NO_INLINE;
+static
+void sync_recv(void) {
+  for (uint8_t i = 0; i < SERIAL_DELAY*5 && serial_read_pin(); i++ ) {
+  }
+  // This shouldn't hang if the target disconnects because the
+  // serial line will float to high if the target does disconnect.
+  while (!serial_read_pin());
+}
+
+// Used by the reciver to send a synchronization signal to the sender.
+static void sync_send(void) NO_INLINE;
+static
+void sync_send(void) {
+  serial_low();
+  serial_delay();
+  serial_high();
+}
+
+// Reads a byte from the serial line
+static uint8_t serial_read_chunk(uint8_t *pterrcount, uint8_t bit) NO_INLINE;
+static uint8_t serial_read_chunk(uint8_t *pterrcount, uint8_t bit) {
+    uint8_t byte, i, p, pb;
+
+  _delay_sub_us(READ_WRITE_START_ADJUST);
+  for( i = 0, byte = 0, p = PARITY; i < bit; i++ ) {
+      serial_delay_half1();   // read the middle of pulses
+      if( serial_read_pin() ) {
+          byte = (byte << 1) | 1; p ^= 1;
+      } else {
+          byte = (byte << 1) | 0; p ^= 0;
+      }
+      _delay_sub_us(READ_WRITE_WIDTH_ADJUST);
+      serial_delay_half2();
+  }
+  /* recive parity bit */
+  serial_delay_half1();   // read the middle of pulses
+  pb = serial_read_pin();
+  _delay_sub_us(READ_WRITE_WIDTH_ADJUST);
+  serial_delay_half2();
+
+  *pterrcount += (p != pb)? 1 : 0;
+
+  return byte;
+}
+
+// Sends a byte with MSB ordering
+void serial_write_chunk(uint8_t data, uint8_t bit) NO_INLINE;
+void serial_write_chunk(uint8_t data, uint8_t bit) {
+    uint8_t b, p;
+    for( p = PARITY, b = 1<<(bit-1); b ; b >>= 1) {
+        if(data & b) {
+            serial_high(); p ^= 1;
+        } else {
+            serial_low();  p ^= 0;
+        }
+        serial_delay();
+    }
+    /* send parity bit */
+    if(p & 1) { serial_high(); }
+    else      { serial_low(); }
+    serial_delay();
+
+    serial_low(); // sync_send() / senc_recv() need raise edge
+}
+
+static void serial_send_packet(uint8_t *buffer, uint8_t size) NO_INLINE;
+static
+void serial_send_packet(uint8_t *buffer, uint8_t size) {
+  for (uint8_t i = 0; i < size; ++i) {
+    uint8_t data;
+    data = buffer[i];
+    sync_send();
+    serial_write_chunk(data,8);
+  }
+}
+
+static uint8_t serial_recive_packet(uint8_t *buffer, uint8_t size) NO_INLINE;
+static
+uint8_t serial_recive_packet(uint8_t *buffer, uint8_t size) {
+  uint8_t pecount = 0;
+  for (uint8_t i = 0; i < size; ++i) {
+    uint8_t data;
+    sync_recv();
+    data = serial_read_chunk(&pecount, 8);
+    buffer[i] = data;
+  }
+  return pecount == 0;
+}
+
+inline static
+void change_sender2reciver(void) {
+    sync_send();          //0
+    serial_delay_half1(); //1
+    serial_low();         //2
+    serial_input_with_pullup(); //2
+    serial_delay_half1(); //3
+}
+
+inline static
+void change_reciver2sender(void) {
+    sync_recv();     //0
+    serial_delay();  //1
+    serial_low();    //3
+    serial_output(); //3
+    serial_delay_half1(); //4
+}
+
+static inline uint8_t nibble_bits_count(uint8_t bits)
+{
+    bits = (bits & 0x5) + (bits >> 1 & 0x5);
+    bits = (bits & 0x3) + (bits >> 2 & 0x3);
+    return bits;
+}
+
+// interrupt handle to be used by the target device
+ISR(SERIAL_PIN_INTERRUPT) {
+
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+  serial_low();
+  serial_output();
+  SSTD_t *trans = Transaction_table;
+#else
+  // recive transaction table index
+  uint8_t tid, bits;
+  uint8_t pecount = 0;
+  sync_recv();
+  bits = serial_read_chunk(&pecount,7);
+  tid = bits>>3;
+  bits = (bits&7) != nibble_bits_count(tid);
+  if( bits || pecount> 0 || tid > Transaction_table_size ) {
+      return;
+  }
+  serial_delay_half1();
+
+  serial_high(); // response step1 low->high
+  serial_output();
+  _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT*SLAVE_INT_ACK_WIDTH);
+  SSTD_t *trans = &Transaction_table[tid];
+  serial_low(); // response step2 ack high->low
+#endif
+
+  // target send phase
+  if( trans->target2initiator_buffer_size > 0 )
+      serial_send_packet((uint8_t *)trans->target2initiator_buffer,
+                         trans->target2initiator_buffer_size);
+  // target switch to input
+  change_sender2reciver();
+
+  // target recive phase
+  if( trans->initiator2target_buffer_size > 0 ) {
+      if (serial_recive_packet((uint8_t *)trans->initiator2target_buffer,
+                               trans->initiator2target_buffer_size) ) {
+          *trans->status = TRANSACTION_ACCEPTED;
+      } else {
+          *trans->status = TRANSACTION_DATA_ERROR;
+      }
+  } else {
+      *trans->status = TRANSACTION_ACCEPTED;
+  }
+
+  sync_recv(); //weit initiator output to high
+}
+
+/////////
+//  start transaction by initiator
+//
+// int  soft_serial_transaction(int sstd_index)
+//
+// Returns:
+//    TRANSACTION_END
+//    TRANSACTION_NO_RESPONSE
+//    TRANSACTION_DATA_ERROR
+// this code is very time dependent, so we need to disable interrupts
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+int  soft_serial_transaction(void) {
+  SSTD_t *trans = Transaction_table;
+#else
+int  soft_serial_transaction(int sstd_index) {
+  if( sstd_index > Transaction_table_size )
+      return TRANSACTION_TYPE_ERROR;
+  SSTD_t *trans = &Transaction_table[sstd_index];
+#endif
+  cli();
+
+  // signal to the target that we want to start a transaction
+  serial_output();
+  serial_low();
+  _delay_us(SLAVE_INT_WIDTH_US);
+
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+  // wait for the target response
+  serial_input_with_pullup();
+  _delay_us(SLAVE_INT_RESPONSE_TIME);
+
+  // check if the target is present
+  if (serial_read_pin()) {
+    // target failed to pull the line low, assume not present
+    serial_output();
+    serial_high();
+    *trans->status = TRANSACTION_NO_RESPONSE;
+    sei();
+    return TRANSACTION_NO_RESPONSE;
+  }
+
+#else
+  // send transaction table index
+  int tid = (sstd_index<<3) | (7 & nibble_bits_count(sstd_index));
+  sync_send();
+  _delay_sub_us(TID_SEND_ADJUST);
+  serial_write_chunk(tid, 7);
+  serial_delay_half1();
+
+  // wait for the target response (step1 low->high)
+  serial_input_with_pullup();
+  while( !serial_read_pin() ) {
+      _delay_sub_us(2);
+  }
+
+  // check if the target is present (step2 high->low)
+  for( int i = 0; serial_read_pin(); i++ ) {
+      if (i > SLAVE_INT_ACK_WIDTH + 1) {
+          // slave failed to pull the line low, assume not present
+          serial_output();
+          serial_high();
+          *trans->status = TRANSACTION_NO_RESPONSE;
+          sei();
+          return TRANSACTION_NO_RESPONSE;
+      }
+      _delay_sub_us(SLAVE_INT_ACK_WIDTH_UNIT);
+  }
+#endif
+
+  // initiator recive phase
+  // if the target is present syncronize with it
+  if( trans->target2initiator_buffer_size > 0 ) {
+      if (!serial_recive_packet((uint8_t *)trans->target2initiator_buffer,
+                                trans->target2initiator_buffer_size) ) {
+          serial_output();
+          serial_high();
+          *trans->status = TRANSACTION_DATA_ERROR;
+          sei();
+          return TRANSACTION_DATA_ERROR;
+      }
+   }
+
+  // initiator switch to output
+  change_reciver2sender();
+
+  // initiator send phase
+  if( trans->initiator2target_buffer_size > 0 ) {
+      serial_send_packet((uint8_t *)trans->initiator2target_buffer,
+                         trans->initiator2target_buffer_size);
+  }
+
+  // always, release the line when not in use
+  sync_send();
+
+  *trans->status = TRANSACTION_END;
+  sei();
+  return TRANSACTION_END;
+}
+
+#ifdef SERIAL_USE_MULTI_TRANSACTION
+int soft_serial_get_and_clean_status(int sstd_index) {
+    SSTD_t *trans = &Transaction_table[sstd_index];
+    cli();
+    int retval = *trans->status;
+    *trans->status = 0;;
+    sei();
+    return retval;
+}
+#endif
+
+#endif
+
+// Helix serial.c history
+//   2018-1-29 fork from let's split and add PD2, modify sync_recv() (#2308, bceffdefc)
+//   2018-6-28 bug fix master to slave comm and speed up (#3255, 1038bbef4)
+//             (adjusted with avr-gcc 4.9.2)
+//   2018-7-13 remove USE_SERIAL_PD2 macro (#3374, f30d6dd78)
+//             (adjusted with avr-gcc 4.9.2)
+//   2018-8-11 add support multi-type transaction (#3608, feb5e4aae)
+//             (adjusted with avr-gcc 4.9.2)
+//   2018-10-21 fix serial and RGB animation conflict (#4191, 4665e4fff)
+//             (adjusted with avr-gcc 7.3.0)
+//   2018-10-28 re-adjust compiler depend value of delay (#4269, 8517f8a66)
+//             (adjusted with avr-gcc 5.4.0, 7.3.0)
diff --git a/keyboards/claw44/serial.h b/keyboards/claw44/serial.h
new file mode 100644
index 000000000..7e0c0847a
--- /dev/null
+++ b/keyboards/claw44/serial.h
@@ -0,0 +1,84 @@
+#ifndef SOFT_SERIAL_H
+#define SOFT_SERIAL_H
+
+#include <stdbool.h>
+
+// /////////////////////////////////////////////////////////////////
+// Need Soft Serial defines in config.h
+// /////////////////////////////////////////////////////////////////
+// ex.
+//  #define SOFT_SERIAL_PIN ??   // ?? = D0,D1,D2,D3,E6
+//  OPTIONAL: #define SELECT_SOFT_SERIAL_SPEED ? // ? = 1,2,3,4,5
+//                                               //  1: about 137kbps (default)
+//                                               //  2: about 75kbps
+//                                               //  3: about 39kbps
+//                                               //  4: about 26kbps
+//                                               //  5: about 20kbps
+//
+// //// USE Simple API (OLD API, compatible with let's split serial.c)
+// ex.
+//  #define SERIAL_SLAVE_BUFFER_LENGTH MATRIX_ROWS/2
+//  #define SERIAL_MASTER_BUFFER_LENGTH 1
+//
+// //// USE flexible API (using multi-type transaction function)
+//  #define SERIAL_USE_MULTI_TRANSACTION
+//
+// /////////////////////////////////////////////////////////////////
+
+
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+/* --- USE Simple API (OLD API, compatible with let's split serial.c) */
+#if SERIAL_SLAVE_BUFFER_LENGTH > 0
+extern volatile uint8_t serial_slave_buffer[SERIAL_SLAVE_BUFFER_LENGTH];
+#endif
+#if SERIAL_MASTER_BUFFER_LENGTH > 0
+extern volatile uint8_t serial_master_buffer[SERIAL_MASTER_BUFFER_LENGTH];
+#endif
+
+void serial_master_init(void);
+void serial_slave_init(void);
+int serial_update_buffers(void);
+
+#endif // USE Simple API
+
+// Soft Serial Transaction Descriptor
+typedef struct _SSTD_t  {
+    uint8_t *status;
+    uint8_t initiator2target_buffer_size;
+    uint8_t *initiator2target_buffer;
+    uint8_t target2initiator_buffer_size;
+    uint8_t *target2initiator_buffer;
+} SSTD_t;
+#define TID_LIMIT( table ) (sizeof(table) / sizeof(SSTD_t))
+
+// initiator is transaction start side
+void soft_serial_initiator_init(SSTD_t *sstd_table, int sstd_table_size);
+// target is interrupt accept side
+void soft_serial_target_init(SSTD_t *sstd_table, int sstd_table_size);
+
+// initiator resullt
+#define TRANSACTION_END 0
+#define TRANSACTION_NO_RESPONSE 0x1
+#define TRANSACTION_DATA_ERROR  0x2
+#define TRANSACTION_TYPE_ERROR  0x4
+#ifndef SERIAL_USE_MULTI_TRANSACTION
+int  soft_serial_transaction(void);
+#else
+int  soft_serial_transaction(int sstd_index);
+#endif
+
+// target status
+// *SSTD_t.status has
+//   initiator:
+//       TRANSACTION_END
+//    or TRANSACTION_NO_RESPONSE
+//    or TRANSACTION_DATA_ERROR
+//   target:
+//       TRANSACTION_DATA_ERROR
+//    or TRANSACTION_ACCEPTED
+#define TRANSACTION_ACCEPTED 0x8
+#ifdef SERIAL_USE_MULTI_TRANSACTION
+int  soft_serial_get_and_clean_status(int sstd_index);
+#endif
+
+#endif /* SOFT_SERIAL_H */
diff --git a/keyboards/claw44/ssd1306.c b/keyboards/claw44/ssd1306.c
new file mode 100644
index 000000000..781c72263
--- /dev/null
+++ b/keyboards/claw44/ssd1306.c
@@ -0,0 +1,346 @@
+#ifdef SSD1306OLED
+
+#include "ssd1306.h"
+#include "i2c.h"
+#include <string.h>
+#include "print.h"
+#ifdef ADAFRUIT_BLE_ENABLE
+#include "adafruit_ble.h"
+#endif
+#ifdef PROTOCOL_LUFA
+#include "lufa.h"
+#endif
+#include "sendchar.h"
+#include "timer.h"
+
+static const unsigned char font[] PROGMEM;
+
+// Set this to 1 to help diagnose early startup problems
+// when testing power-on with ble.  Turn it off otherwise,
+// as the latency of printing most of the debug info messes
+// with the matrix scan, causing keys to drop.
+#define DEBUG_TO_SCREEN 0
+
+//static uint16_t last_battery_update;
+//static uint32_t vbat;
+//#define BatteryUpdateInterval 10000 /* milliseconds */
+
+// 'last_flush' is declared as uint16_t,
+// so this must be less than 65535 
+#define ScreenOffInterval 60000 /* milliseconds */
+#if DEBUG_TO_SCREEN
+static uint8_t displaying;
+#endif
+static uint16_t last_flush;
+
+static bool force_dirty = true;
+
+// Write command sequence.
+// Returns true on success.
+static inline bool _send_cmd1(uint8_t cmd) {
+  bool res = false;
+
+  if (i2c_start_write(SSD1306_ADDRESS)) {
+    xprintf("failed to start write to %d\n", SSD1306_ADDRESS);
+    goto done;
+  }
+
+  if (i2c_master_write(0x0 /* command byte follows */)) {
+    print("failed to write control byte\n");
+
+    goto done;
+  }
+
+  if (i2c_master_write(cmd)) {
+    xprintf("failed to write command %d\n", cmd);
+    goto done;
+  }
+  res = true;
+done:
+  i2c_master_stop();
+  return res;
+}
+
+// Write 2-byte command sequence.
+// Returns true on success
+static inline bool _send_cmd2(uint8_t cmd, uint8_t opr) {
+  if (!_send_cmd1(cmd)) {
+    return false;
+  }
+  return _send_cmd1(opr);
+}
+
+// Write 3-byte command sequence.
+// Returns true on success
+static inline bool _send_cmd3(uint8_t cmd, uint8_t opr1, uint8_t opr2) {
+  if (!_send_cmd1(cmd)) {
+    return false;
+  }
+  if (!_send_cmd1(opr1)) {
+    return false;
+  }
+  return _send_cmd1(opr2);
+}
+
+#define send_cmd1(c) if (!_send_cmd1(c)) {goto done;}
+#define send_cmd2(c,o) if (!_send_cmd2(c,o)) {goto done;}
+#define send_cmd3(c,o1,o2) if (!_send_cmd3(c,o1,o2)) {goto done;}
+
+static void clear_display(void) {
+  matrix_clear(&display);
+
+  // Clear all of the display bits (there can be random noise
+  // in the RAM on startup)
+  send_cmd3(PageAddr, 0, (DisplayHeight / 8) - 1);
+  send_cmd3(ColumnAddr, 0, DisplayWidth - 1);
+
+  if (i2c_start_write(SSD1306_ADDRESS)) {
+    goto done;
+  }
+  if (i2c_master_write(0x40)) {
+    // Data mode
+    goto done;
+  }
+  for (uint8_t row = 0; row < MatrixRows; ++row) {
+    for (uint8_t col = 0; col < DisplayWidth; ++col) {
+      i2c_master_write(0);
+    }
+  }
+
+  display.dirty = false;
+
+done:
+  i2c_master_stop();
+}
+
+#if DEBUG_TO_SCREEN
+#undef sendchar
+static int8_t capture_sendchar(uint8_t c) {
+  sendchar(c);
+  iota_gfx_write_char(c);
+
+  if (!displaying) {
+    iota_gfx_flush();
+  }
+  return 0;
+}
+#endif
+
+bool iota_gfx_init(bool rotate) {
+  bool success = false;
+
+  i2c_master_init();
+  send_cmd1(DisplayOff);
+  send_cmd2(SetDisplayClockDiv, 0x80);
+  send_cmd2(SetMultiPlex, DisplayHeight - 1);
+
+  send_cmd2(SetDisplayOffset, 0);
+
+
+  send_cmd1(SetStartLine | 0x0);
+  send_cmd2(SetChargePump, 0x14 /* Enable */);
+  send_cmd2(SetMemoryMode, 0 /* horizontal addressing */);
+
+  if(rotate){
+    // the following Flip the display orientation 180 degrees
+    send_cmd1(SegRemap);
+    send_cmd1(ComScanInc);
+  }else{
+    // Flips the display orientation 0 degrees
+    send_cmd1(SegRemap | 0x1);
+    send_cmd1(ComScanDec);
+  }
+
+  send_cmd2(SetComPins, 0x2);
+  send_cmd2(SetContrast, 0x8f);
+  send_cmd2(SetPreCharge, 0xf1);
+  send_cmd2(SetVComDetect, 0x40);
+  send_cmd1(DisplayAllOnResume);
+  send_cmd1(NormalDisplay);
+  send_cmd1(DeActivateScroll);
+  send_cmd1(DisplayOn);
+
+  send_cmd2(SetContrast, 0); // Dim
+
+  clear_display();
+
+  success = true;
+
+  iota_gfx_flush();
+
+#if DEBUG_TO_SCREEN
+  print_set_sendchar(capture_sendchar);
+#endif
+
+done:
+  return success;
+}
+
+bool iota_gfx_off(void) {
+  bool success = false;
+
+  send_cmd1(DisplayOff);
+  success = true;
+
+done:
+  return success;
+}
+
+bool iota_gfx_on(void) {
+  bool success = false;
+
+  send_cmd1(DisplayOn);
+  success = true;
+
+done:
+  return success;
+}
+
+void matrix_write_char_inner(struct CharacterMatrix *matrix, uint8_t c) {
+  *matrix->cursor = c;
+  ++matrix->cursor;
+
+  if (matrix->cursor - &matrix->display[0][0] == sizeof(matrix->display)) {
+    // We went off the end; scroll the display upwards by one line
+    memmove(&matrix->display[0], &matrix->display[1],
+            MatrixCols * (MatrixRows - 1));
+    matrix->cursor = &matrix->display[MatrixRows - 1][0];
+    memset(matrix->cursor, ' ', MatrixCols);
+  }
+}
+
+void matrix_write_char(struct CharacterMatrix *matrix, uint8_t c) {
+  matrix->dirty = true;
+
+  if (c == '\n') {
+    // Clear to end of line from the cursor and then move to the
+    // start of the next line
+    uint8_t cursor_col = (matrix->cursor - &matrix->display[0][0]) % MatrixCols;
+
+    while (cursor_col++ < MatrixCols) {
+      matrix_write_char_inner(matrix, ' ');
+    }
+    return;
+  }
+
+  matrix_write_char_inner(matrix, c);
+}
+
+void iota_gfx_write_char(uint8_t c) {
+  matrix_write_char(&display, c);
+}
+
+void matrix_write(struct CharacterMatrix *matrix, const char *data) {
+  const char *end = data + strlen(data);
+  while (data < end) {
+    matrix_write_char(matrix, *data);
+    ++data;
+  }
+}
+
+void matrix_write_ln(struct CharacterMatrix *matrix, const char *data) {
+  char data_ln[strlen(data)+2];
+  snprintf(data_ln, sizeof(data_ln), "%s\n", data);
+  matrix_write(matrix, data_ln);
+}
+
+void iota_gfx_write(const char *data) {
+  matrix_write(&display, data);
+}
+
+void matrix_write_P(struct CharacterMatrix *matrix, const char *data) {
+  while (true) {
+    uint8_t c = pgm_read_byte(data);
+    if (c == 0) {
+      return;
+    }
+    matrix_write_char(matrix, c);
+    ++data;
+  }
+}
+
+void iota_gfx_write_P(const char *data) {
+  matrix_write_P(&display, data);
+}
+
+void matrix_clear(struct CharacterMatrix *matrix) {
+  memset(matrix->display, ' ', sizeof(matrix->display));
+  matrix->cursor = &matrix->display[0][0];
+  matrix->dirty = true;
+}
+
+void iota_gfx_clear_screen(void) {
+  matrix_clear(&display);
+}
+
+void matrix_render(struct CharacterMatrix *matrix) {
+  last_flush = timer_read();
+  iota_gfx_on();
+#if DEBUG_TO_SCREEN
+  ++displaying;
+#endif
+
+  // Move to the home position
+  send_cmd3(PageAddr, 0, MatrixRows - 1);
+  send_cmd3(ColumnAddr, 0, (MatrixCols * FontWidth) - 1);
+
+  if (i2c_start_write(SSD1306_ADDRESS)) {
+    goto done;
+  }
+  if (i2c_master_write(0x40)) {
+    // Data mode
+    goto done;
+  }
+
+  for (uint8_t row = 0; row < MatrixRows; ++row) {
+    for (uint8_t col = 0; col < MatrixCols; ++col) {
+      const uint8_t *glyph = font + (matrix->display[row][col] * FontWidth);
+
+      for (uint8_t glyphCol = 0; glyphCol < FontWidth; ++glyphCol) {
+        uint8_t colBits = pgm_read_byte(glyph + glyphCol);
+        i2c_master_write(colBits);
+      }
+
+      // 1 column of space between chars (it's not included in the glyph)
+      //i2c_master_write(0);
+    }
+  }
+
+  matrix->dirty = false;
+
+done:
+  i2c_master_stop();
+#if DEBUG_TO_SCREEN
+  --displaying;
+#endif
+}
+
+void iota_gfx_flush(void) {
+  matrix_render(&display);
+}
+
+__attribute__ ((weak))
+void iota_gfx_task_user(void) {
+}
+
+void iota_gfx_task(void) {
+  iota_gfx_task_user();
+
+  if (display.dirty|| force_dirty) {
+    iota_gfx_flush();
+    force_dirty = false;
+  }
+
+  /*
+  if (timer_elapsed(last_flush) > ScreenOffInterval) {
+    iota_gfx_off();
+  }
+  */
+}
+
+bool process_record_gfx(uint16_t keycode, keyrecord_t *record) {
+  force_dirty = true;
+  return true;
+}
+
+#endif
diff --git a/keyboards/claw44/ssd1306.h b/keyboards/claw44/ssd1306.h
new file mode 100644
index 000000000..ea8c92328
--- /dev/null
+++ b/keyboards/claw44/ssd1306.h
@@ -0,0 +1,91 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stdio.h>
+#include "pincontrol.h"
+#include "action.h"
+
+enum ssd1306_cmds {
+  DisplayOff = 0xAE,
+  DisplayOn = 0xAF,
+
+  SetContrast = 0x81,
+  DisplayAllOnResume = 0xA4,
+
+  DisplayAllOn = 0xA5,
+  NormalDisplay = 0xA6,
+  InvertDisplay = 0xA7,
+  SetDisplayOffset = 0xD3,
+  SetComPins = 0xda,
+  SetVComDetect = 0xdb,
+  SetDisplayClockDiv = 0xD5,
+  SetPreCharge = 0xd9,
+  SetMultiPlex = 0xa8,
+  SetLowColumn = 0x00,
+  SetHighColumn = 0x10,
+  SetStartLine = 0x40,
+
+  SetMemoryMode = 0x20,
+  ColumnAddr = 0x21,
+  PageAddr = 0x22,
+
+  ComScanInc = 0xc0,
+  ComScanDec = 0xc8,
+  SegRemap = 0xa0,
+  SetChargePump = 0x8d,
+  ExternalVcc = 0x01,
+  SwitchCapVcc = 0x02,
+
+  ActivateScroll = 0x2f,
+  DeActivateScroll = 0x2e,
+  SetVerticalScrollArea = 0xa3,
+  RightHorizontalScroll = 0x26,
+  LeftHorizontalScroll = 0x27,
+  VerticalAndRightHorizontalScroll = 0x29,
+  VerticalAndLeftHorizontalScroll = 0x2a,
+};
+
+// Controls the SSD1306 128x32 OLED display via i2c
+
+#ifndef SSD1306_ADDRESS
+#define SSD1306_ADDRESS 0x3C
+#endif
+
+#define DisplayHeight 32
+#define DisplayWidth 128
+
+#define FontHeight 8
+#define FontWidth 6
+
+#define MatrixRows (DisplayHeight / FontHeight)
+#define MatrixCols (DisplayWidth / FontWidth)
+
+struct CharacterMatrix {
+  uint8_t display[MatrixRows][MatrixCols];
+  uint8_t *cursor;
+  bool dirty;
+};
+
+struct CharacterMatrix display;
+
+bool iota_gfx_init(bool rotate);
+void iota_gfx_task(void);
+bool iota_gfx_off(void);
+bool iota_gfx_on(void);
+void iota_gfx_flush(void);
+void iota_gfx_write_char(uint8_t c);
+void iota_gfx_write(const char *data);
+void iota_gfx_write_P(const char *data);
+void iota_gfx_clear_screen(void);
+
+void iota_gfx_task_user(void);
+
+void matrix_clear(struct CharacterMatrix *matrix);
+void matrix_write_char_inner(struct CharacterMatrix *matrix, uint8_t c);
+void matrix_write_char(struct CharacterMatrix *matrix, uint8_t c);
+void matrix_write(struct CharacterMatrix *matrix, const char *data);
+void matrix_write_ln(struct CharacterMatrix *matrix, const char *data);
+void matrix_write_P(struct CharacterMatrix *matrix, const char *data);
+void matrix_render(struct CharacterMatrix *matrix);
+
+bool process_record_gfx(uint16_t keycode, keyrecord_t *record);
\ No newline at end of file