diff --git a/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_bot_scsi.c b/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_bot_scsi.c
index 4ee146b19c..8e8e740ff8 100644
--- a/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_bot_scsi.c
+++ b/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_bot_scsi.c
@@ -144,6 +144,7 @@ void bot_scsi_reset(void *udev)
   */
 void bot_scsi_datain_handler(void *udev, uint8_t ept_num)
 {
+  UNUSED(ept_num);
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
   switch(pmsc->msc_state)
@@ -173,6 +174,7 @@ void bot_scsi_datain_handler(void *udev, uint8_t ept_num)
   */
 void bot_scsi_dataout_handler(void *udev, uint8_t ept_num)
 {
+  UNUSED(ept_num);
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
   switch(pmsc->msc_state)
@@ -289,6 +291,7 @@ void bot_scsi_send_csw(void *udev, uint8_t status)
   */
 void bot_scsi_sense_code(void *udev, uint8_t sense_key, uint8_t asc)
 {
+  UNUSED(udev);
   sense_data.sense_key = sense_key;
   sense_data.asc = asc;
 }
@@ -347,6 +350,8 @@ void bot_scsi_stall(void *udev)
   */
 usb_sts_type bot_scsi_test_unit(void *udev, uint8_t lun)
 {
+  UNUSED(udev);
+  UNUSED(lun);
   usb_sts_type status = USB_OK;
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
@@ -410,6 +415,7 @@ usb_sts_type bot_scsi_inquiry(void *udev, uint8_t lun)
   */
 usb_sts_type bot_scsi_start_stop(void *udev, uint8_t lun)
 {
+  UNUSED(lun);
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
   pmsc->data_len = 0;
@@ -424,6 +430,7 @@ usb_sts_type bot_scsi_start_stop(void *udev, uint8_t lun)
   */
 usb_sts_type bot_scsi_allow_medium_removal(void *udev, uint8_t lun)
 {
+  UNUSED(lun);
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
   pmsc->data_len = 0;
@@ -438,6 +445,7 @@ usb_sts_type bot_scsi_allow_medium_removal(void *udev, uint8_t lun)
   */
 usb_sts_type bot_scsi_mode_sense6(void *udev, uint8_t lun)
 {
+  UNUSED(lun);
   uint8_t data_len = 8;
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
@@ -447,6 +455,12 @@ usb_sts_type bot_scsi_mode_sense6(void *udev, uint8_t lun)
     data_len --;
     pmsc->data[data_len] = mode_sense6_data[data_len];
   };
+
+  // set bit 7 of the device configuration byte to indicate write protection
+  if (msc_get_readonly(lun)) {
+	  pmsc->data[2] |= 1 << 7;
+  }
+
   return USB_OK;
 }
 
@@ -458,6 +472,7 @@ usb_sts_type bot_scsi_mode_sense6(void *udev, uint8_t lun)
   */
 usb_sts_type bot_scsi_mode_sense10(void *udev, uint8_t lun)
 {
+  UNUSED(lun);
   uint8_t data_len = 8;
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
@@ -540,6 +555,7 @@ usb_sts_type bot_scsi_format_capacity(void *udev, uint8_t lun)
   */
 usb_sts_type bot_scsi_request_sense(void *udev, uint8_t lun)
 {
+  UNUSED(lun);
   uint32_t trans_len = 0x12;
   usbd_core_type *pudev = (usbd_core_type *)udev;
   msc_type *pmsc = (msc_type *)pudev->class_handler->pdata;
@@ -633,7 +649,7 @@ usb_sts_type bot_scsi_read10(void *udev, uint8_t lun)
   pmsc->data_len = MSC_MAX_DATA_BUF_LEN;
 
   len = MIN(pmsc->blk_len, MSC_MAX_DATA_BUF_LEN);
-  if( msc_disk_read(lun, pmsc->blk_addr, pmsc->data, len) != USB_OK)
+  if( msc_disk_read(lun, pmsc->blk_addr / pmsc->blk_size[lun], pmsc->data, len / pmsc->blk_size[lun]) != USB_OK)
   {
     bot_scsi_sense_code(udev, SENSE_KEY_HARDWARE_ERROR, MEDIUM_NOT_PRESENT);
     return USB_FAIL;
@@ -698,7 +714,7 @@ usb_sts_type bot_scsi_write10(void *udev, uint8_t lun)
   else
   {
     len = MIN(pmsc->blk_len, MSC_MAX_DATA_BUF_LEN);
-    if(msc_disk_write(lun, pmsc->blk_addr, pmsc->data, len) != USB_OK)
+    if(msc_disk_write(lun, pmsc->blk_addr / pmsc->blk_size[lun], pmsc->data, len / pmsc->blk_size[lun]) != USB_OK)
     {
       bot_scsi_sense_code(udev, SENSE_KEY_HARDWARE_ERROR, MEDIUM_NOT_PRESENT);
       return USB_FAIL;
diff --git a/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_class.c b/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_class.c
index 9c890bcea8..645c0749c3 100644
--- a/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_class.c
+++ b/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_class.c
@@ -23,7 +23,7 @@
   */
 #include "usbd_core.h"
 #include "msc_class.h"
-#include "msc_desc.h"
+#include <msc_desc.h>
 #include "msc_bot_scsi.h"
 
 /** @addtogroup AT32F435_437_middlewares_usbd_class
@@ -183,6 +183,7 @@ static usb_sts_type class_setup_handler(void *udev, usb_setup_type *setup)
   */
 static usb_sts_type class_ept0_tx_handler(void *udev)
 {
+	UNUSED(udev);
   usb_sts_type status = USB_OK;
 
   /* ...user code... */
@@ -199,7 +200,7 @@ static usb_sts_type class_ept0_rx_handler(void *udev)
 {
   usb_sts_type status = USB_OK;
   usbd_core_type *pudev = (usbd_core_type *)udev;
-  uint32_t recv_len = usbd_get_recv_len(pudev, 0);
+  usbd_get_recv_len(pudev, 0);
   /* ...user code... */
   return status;
 }
@@ -240,6 +241,7 @@ static usb_sts_type class_out_handler(void *udev, uint8_t ept_num)
   */
 static usb_sts_type class_sof_handler(void *udev)
 {
+	UNUSED(udev);
   usb_sts_type status = USB_OK;
 
   /* ...user code... */
@@ -255,6 +257,7 @@ static usb_sts_type class_sof_handler(void *udev)
   */
 static usb_sts_type class_event_handler(void *udev, usbd_event_type event)
 {
+	UNUSED(udev);
   usb_sts_type status = USB_OK;
   switch(event)
   {
diff --git a/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_desc.c b/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_desc.c
index 56cac13a8a..1eea5b9b5f 100644
--- a/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_desc.c
+++ b/lib/main/AT32F43x/middlewares/usbd_class/msc/msc_desc.c
@@ -25,7 +25,7 @@
 #include "usb_std.h"
 #include "usbd_sdr.h"
 #include "usbd_core.h"
-#include "msc_desc.h"
+#include <msc_desc.h>
 
 /** @addtogroup AT32F435_437_middlewares_usbd_class
   * @{
diff --git a/make/mcu/AT32F4.mk b/make/mcu/AT32F4.mk
index b14d835e32..4e2f386420 100644
--- a/make/mcu/AT32F4.mk
+++ b/make/mcu/AT32F4.mk
@@ -2,5 +2,61 @@
 # AT32F4 Make file include
 #
 
+CMSIS_DIR         := $(ROOT)/lib/main/AT32F43x/cmsis
+STDPERIPH_DIR   = $(ROOT)/lib/main/AT32F43x/drivers
+MIDDLEWARES_DIR = $(ROOT)/lib/main/AT32F43x/middlewares
+STDPERIPH_SRC   = $(wildcard $(STDPERIPH_DIR)/src/*.c) \
+                  $(wildcard $(MIDDLEWARES_DIR)/usb_drivers/src/*.c) \
+                  $(wildcard $(MIDDLEWARES_DIR)/usbd_class/msc/*.c)
+
+EXCLUDES        = at32f435_437_dvp.c \
+                  at32f435_437_can.c \
+                  at32f435_437_xmc.c \
+                  at32f435_437_emac
+
+
+STARTUP_SRC     = at32/startup_at32f435_437.s
+STDPERIPH_SRC   := $(filter-out ${EXCLUDES}, $(STDPERIPH_SRC))
+
+VPATH           := $(VPATH):$(ROOT)/lib/main/AT32F43x/cmsis/cm4/core_support:$(STDPERIPH_DIR)/src:$(STDPERIPH_DIR)/inc:$(SRC_DIR)/startup/at32
+
+VCP_SRC =          $(wildcard $(ROOT)/lib/main/AT32F43x/middlewares/usbd_class/cdc/*.c) \
+                   drivers/usb_io.c
+
+VCP_INCLUDES =     $(ROOT)/lib/main/AT32F43x/middlewares/usb_drivers/inc \
+                   $(ROOT)/lib/main/AT32F43x/middlewares/usbd_class/cdc
+
+DEVICE_STDPERIPH_SRC = $(STDPERIPH_SRC)
+
 INCLUDE_DIRS    := $(INCLUDE_DIRS) \
-                   $(ROOT)/src/main/drivers/at32
+                   $(SRC_DIR)/startup/at32 \
+                   $(SRC_DIR)/drivers \
+                   $(SRC_DIR)/drivers/at32 \
+                   $(STDPERIPH_DIR)/inc \
+                   $(CMSIS_DIR)/cm4/core_support \
+                   $(CMSIS_DIR)/cm4 \
+                   $(MIDDLEWARES_DIR)/i2c_application_library \
+                   $(MIDDLEWARES_DIR)/usbd_class/msc \
+                   $(VCP_INCLUDES)
+
+LD_SCRIPT       = $(LINKER_DIR)/at32_flash_f43xM.ld
+
+ARCH_FLAGS      = -std=c99  -mthumb -mcpu=cortex-m4 -march=armv7e-m -mfloat-abi=hard -mfpu=fpv4-sp-d16 -fsingle-precision-constant -Wdouble-promotion
+DEVICE_FLAGS   += -DUSE_ATBSP_DRIVER -DAT32F43x -DHSE_VALUE=$(HSE_VALUE) -DAT32 -DUSE_OTG_HOST_MODE
+
+MCU_COMMON_SRC = \
+    $(addprefix startup/at32/,$(notdir $(wildcard $(SRC_DIR)/startup/at32/*.c))) \
+    $(addprefix drivers/at32/,$(notdir $(wildcard $(SRC_DIR)/drivers/at32/*.c))) \
+    drivers/accgyro/accgyro_mpu.c \
+    drivers/dshot_bitbang_decode.c \
+    drivers/inverter.c \
+    drivers/pwm_output_dshot_shared.c \
+    $(MIDDLEWARES_DIR)/i2c_application_library/i2c_application.c \
+    drivers/bus_i2c_timing.c \
+    drivers/usb_msc_common.c \
+    msc/usbd_storage.c \
+    msc/usbd_storage_emfat.c \
+    msc/emfat.c \
+    msc/emfat_file.c
+
+MCU_EXCLUDES =
diff --git a/make/mcu/STM32F4.mk b/make/mcu/STM32F4.mk
index 349541825e..e95af2e40f 100644
--- a/make/mcu/STM32F4.mk
+++ b/make/mcu/STM32F4.mk
@@ -180,6 +180,7 @@ MCU_COMMON_SRC = \
             drivers/stm32/timer_stdperiph.c \
             drivers/stm32/timer_stm32f4xx.c \
             drivers/stm32/transponder_ir_io_stdperiph.c \
+            drivers/stm32/usbd_msc_desc.c \
             startup/system_stm32f4xx.c
 
 ifeq ($(PERIPH_DRIVER), HAL)
@@ -204,7 +205,6 @@ endif
 MSC_SRC = \
             drivers/usb_msc_common.c \
             drivers/stm32/usb_msc_f4xx.c \
-            msc/usbd_msc_desc.c \
             msc/usbd_storage.c \
             msc/usbd_storage_emfat.c \
             msc/emfat.c \
diff --git a/src/config/REVO_AT/config.h b/src/config/REVO_AT/config.h
index f253ff71b9..38617071b3 100644
--- a/src/config/REVO_AT/config.h
+++ b/src/config/REVO_AT/config.h
@@ -26,7 +26,8 @@
 #define BOARD_NAME        REVO_AT
 #define MANUFACTURER_ID   OPEN
 
-#define LED0_PIN                PB5
+#define LED0_PIN             PB5
+#define LED1_PIN             PB4
 
 #define USE_GYRO
 #define USE_GYRO_SPI_MPU6000
@@ -41,13 +42,12 @@
 #define USE_GYRO_EXTI
 #define GYRO_1_EXTI_PIN         PC4
 
-#define  SPI1_SCK_PIN           PA5
-#define  SPI1_SDI_PIN           PA6
-#define  SPI1_SDO_PIN           PA7
-
-#define  SPI3_SCK_PIN           PC10
-#define  SPI3_SDI_PIN           PC11
-#define  SPI3_SDO_PIN           PC12
+#define SPI1_SCK_PIN         PA5
+#define SPI3_SCK_PIN         PC10
+#define SPI1_SDI_PIN         PA6
+#define SPI3_SDI_PIN         PC11
+#define SPI1_SDO_PIN         PA7
+#define SPI3_SDO_PIN         PC12
 
 #define USE_FLASH
 #define USE_FLASH_M25P16
@@ -60,8 +60,10 @@
 #define I2C2_SCL_PIN            PB10
 #define I2C2_SDA_PIN            PB11
 
+#define MAG_I2C_INSTANCE        I2CDEV_1
 #define USE_MAG
-#define MAG_I2C_INSTANCE        I2C1
+#define USE_MAG_HMC5883
 
+#define BARO_I2C_INSTANCE       I2CDEV_1
 #define USE_BARO
-#define BARO_I2C_INSTANCE       I2C1
+#define USE_BARO_MS5611
diff --git a/src/main/drivers/at32/msc_desc.h b/src/main/drivers/at32/msc_desc.h
new file mode 100644
index 0000000000..a2c500b67e
--- /dev/null
+++ b/src/main/drivers/at32/msc_desc.h
@@ -0,0 +1,83 @@
+/**
+  **************************************************************************
+  * @file     msc_desc.h
+  * @brief    usb msc descriptor header file
+  **************************************************************************
+  *                       Copyright notice & Disclaimer
+  *
+  * The software Board Support Package (BSP) that is made available to
+  * download from Artery official website is the copyrighted work of Artery.
+  * Artery authorizes customers to use, copy, and distribute the BSP
+  * software and its related documentation for the purpose of design and
+  * development in conjunction with Artery microcontrollers. Use of the
+  * software is governed by this copyright notice and the following disclaimer.
+  *
+  * THIS SOFTWARE IS PROVIDED ON "AS IS" BASIS WITHOUT WARRANTIES,
+  * GUARANTEES OR REPRESENTATIONS OF ANY KIND. ARTERY EXPRESSLY DISCLAIMS,
+  * TO THE FULLEST EXTENT PERMITTED BY LAW, ALL EXPRESS, IMPLIED OR
+  * STATUTORY OR OTHER WARRANTIES, GUARANTEES OR REPRESENTATIONS,
+  * INCLUDING BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY,
+  * FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+  *
+  **************************************************************************
+  */
+
+/* define to prevent recursive inclusion -------------------------------------*/
+#ifndef __MSC_DESC_H
+#define __MSC_DESC_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "msc_class.h"
+#include "usbd_core.h"
+
+/** @addtogroup AT32F435_437_middlewares_usbd_class
+  * @{
+  */
+
+/** @addtogroup USB_msc_desc
+  * @{
+  */
+
+/** @defgroup USB_msc_desc_definition
+  * @{
+  */
+
+#define MSC_BCD_NUM                          0x0110
+
+#define USBD_MSC_VENDOR_ID                   0x2E3C
+#define USBD_MSC_PRODUCT_ID                  0x5720
+
+#define USBD_MSC_CONFIG_DESC_SIZE            32
+#define USBD_MSC_SIZ_STRING_LANGID           4
+#define USBD_MSC_SIZ_STRING_SERIAL           0x1A
+
+#define USBD_MSC_DESC_MANUFACTURER_STRING    "Artery"
+#define USBD_MSC_DESC_PRODUCT_STRING         "Betaflight FC Mass Storage (FS Mode)"
+#define USBD_MSC_DESC_CONFIGURATION_STRING   "MSC Config"
+#define USBD_MSC_DESC_INTERFACE_STRING       "MSC Interface"
+
+#define         MCU_ID1                   (0x1FFFF7E8)
+#define         MCU_ID2                   (0x1FFFF7EC)
+#define         MCU_ID3                   (0x1FFFF7F0)
+
+extern usbd_desc_handler msc_desc_handler;
+
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+
+/**
+  * @}
+  */
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/main/drivers/at32/msc_diskio.h b/src/main/drivers/at32/msc_diskio.h
new file mode 100644
index 0000000000..b55632b47e
--- /dev/null
+++ b/src/main/drivers/at32/msc_diskio.h
@@ -0,0 +1,29 @@
+/*
+ * This file is part of Betaflight.
+ *
+ * Betaflight is free software. You can redistribute
+ * this software and/or modify this software under the terms of the
+ * GNU General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option)
+ * any later version.
+ *
+ * Betaflight is distributed in the hope that they
+ * 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 software.
+ *
+ * If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+// IO routines from usb_msc_at32F435.c
+int8_t msc_disk_capacity(uint8_t lun, uint32_t *block_num, uint32_t *block_size);
+int8_t msc_disk_read(uint8_t lun, uint32_t blk_addr, uint8_t *buf, uint16_t blk_len);
+int8_t msc_disk_write(uint8_t lun, uint32_t blk_addr, uint8_t *buf, uint16_t blk_len);
+uint8_t *get_inquiry(uint8_t lun);
+uint8_t msc_get_readonly(uint8_t lun);
+
diff --git a/src/main/drivers/at32/persistent_at32bsp.c b/src/main/drivers/at32/persistent_at32bsp.c
index be4c06c56e..ab497fcc23 100644
--- a/src/main/drivers/at32/persistent_at32bsp.c
+++ b/src/main/drivers/at32/persistent_at32bsp.c
@@ -39,7 +39,9 @@ uint32_t persistentObjectRead(persistentObjectId_e id)
 
 void persistentObjectWrite(persistentObjectId_e id, uint32_t value)
 {
+    ertc_write_protect_disable();
     ertc_bpr_data_write((ertc_dt_type)id, value);
+    ertc_write_protect_enable();
 }
 
 void persistentObjectRTCEnable(void)
diff --git a/src/main/drivers/at32/platform_mcu.h b/src/main/drivers/at32/platform_mcu.h
index 7aa31bd46b..d9d5fd4082 100644
--- a/src/main/drivers/at32/platform_mcu.h
+++ b/src/main/drivers/at32/platform_mcu.h
@@ -68,6 +68,8 @@ typedef enum {DISABLE = 0, ENABLE = !DISABLE} FunctionalState;
 
 #endif
 
+#define USE_USB_MSC
+
 #define USE_TIMER_MGMT
 #define USE_TIMER_AF
 #define USE_DMA_SPEC
diff --git a/src/main/drivers/at32/system_at32f43x.c b/src/main/drivers/at32/system_at32f43x.c
index 330455fc1b..70ee28a837 100644
--- a/src/main/drivers/at32/system_at32f43x.c
+++ b/src/main/drivers/at32/system_at32f43x.c
@@ -58,7 +58,7 @@ typedef struct isrVector_s {
 
 void checkForBootLoaderRequest(void)
 {
-    uint32_t bootloaderRequest = persistentObjectRead(PERSISTENT_OBJECT_RESET_REASON);
+    volatile uint32_t bootloaderRequest = persistentObjectRead(PERSISTENT_OBJECT_RESET_REASON);
 
     if (bootloaderRequest != RESET_BOOTLOADER_REQUEST_ROM) {
         return;
@@ -96,6 +96,10 @@ bool isMPUSoftReset(void)
 
 void systemInit(void)
 {
+    persistentObjectInit();
+
+    checkForBootLoaderRequest();
+
     system_clock_config();//config system clock to 288mhz usb 48mhz
 
     // Configure NVIC preempt/priority groups
diff --git a/src/main/drivers/at32/usb_msc_at32f43x.c b/src/main/drivers/at32/usb_msc_at32f43x.c
index 4ac913123b..e4ee3d24d0 100644
--- a/src/main/drivers/at32/usb_msc_at32f43x.c
+++ b/src/main/drivers/at32/usb_msc_at32f43x.c
@@ -43,6 +43,9 @@
 #include "drivers/time.h"
 #include "drivers/usb_msc.h"
 
+#include "msc/usbd_storage.h"
+#include "msc/usbd_storage_emfat.h"
+
 #include "pg/sdcard.h"
 #include "pg/usb.h"
 
@@ -194,4 +197,44 @@ uint8_t mscStart(void)
     return 0;
 }
 
+int8_t msc_disk_capacity(uint8_t lun, uint32_t *block_num, uint32_t *block_size)
+{
+    return USBD_MSC_EMFAT_fops.GetCapacity(lun, block_num, block_size);
+}
+
+int8_t msc_disk_read(
+    uint8_t lun,        // logical unit number
+    uint32_t blk_addr,  // address of 1st block to be read
+    uint8_t *buf,       // Pointer to the buffer to save data
+    uint16_t blk_len)   // number of blocks to be read
+{
+    return USBD_MSC_EMFAT_fops.Read(lun, buf, blk_addr, blk_len);
+}
+
+int8_t msc_disk_write(uint8_t lun,
+    uint32_t blk_addr,
+    uint8_t *buf,
+    uint16_t blk_len)
+{
+    UNUSED(lun);
+    UNUSED(buf);
+    UNUSED(blk_addr);
+    UNUSED(blk_len);
+
+    return 1;
+}
+
+uint8_t *get_inquiry(uint8_t lun)
+{
+    UNUSED(lun);
+
+    return (uint8_t *)USBD_MSC_EMFAT_fops.pInquiry;
+}
+
+uint8_t msc_get_readonly(uint8_t lun)
+{
+    UNUSED(lun);
+
+    return 1;
+}
 #endif
diff --git a/src/main/drivers/at32/usbd_msc_mem.h b/src/main/drivers/at32/usbd_msc_mem.h
new file mode 100644
index 0000000000..928a2a8b6f
--- /dev/null
+++ b/src/main/drivers/at32/usbd_msc_mem.h
@@ -0,0 +1,61 @@
+/**
+  ******************************************************************************
+  * @file    usbd_msc_mem.h
+  * @author  MCD Application Team
+  * @version V1.2.0
+  * @date    09-November-2015
+  * @brief   header for the STORAGE DISK file file
+  ******************************************************************************
+  * @attention
+  *
+  * <h2><center>&copy; COPYRIGHT 2015 STMicroelectronics</center></h2>
+  *
+  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
+  * You may not use this file except in compliance with the License.
+  * You may obtain a copy of the License at:
+  *
+  *        http://www.st.com/software_license_agreement_liberty_v2
+  *
+  * Unless required by applicable law or agreed to in writing, software
+  * distributed under the License is distributed on an "AS IS" BASIS,
+  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  * See the License for the specific language governing permissions and
+  * limitations under the License.
+  *
+  ******************************************************************************
+  */
+
+/* Define to prevent recursive inclusion -------------------------------------*/
+
+#pragma once
+
+/** @defgroup USBD_MEM_Exported_Defines
+  * @{
+  */
+#define USBD_STD_INQUIRY_LENGTH     36
+/**
+  * @}
+  */
+
+
+/** @defgroup USBD_MEM_Exported_TypesDefinitions
+  * @{
+  */
+
+typedef struct _USBD_STORAGE
+{
+  int8_t (* Init) (uint8_t lun);
+  int8_t (* GetCapacity) (uint8_t lun, uint32_t *block_num, uint32_t *block_size);
+  int8_t (* IsReady) (uint8_t lun);
+  int8_t (* IsWriteProtected) (uint8_t lun);
+  int8_t (* Read) (uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len);
+  int8_t (* Write)(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len);
+  int8_t (* GetMaxLun)(void);
+  int8_t *pInquiry;
+
+} USBD_STORAGE_cb_TypeDef;
+
+/** @defgroup USBD_MEM_Exported_FunctionsPrototype
+  * @{
+  */
+extern USBD_STORAGE_cb_TypeDef *USBD_STORAGE_fops;
diff --git a/src/main/drivers/stm32/system_stm32f4xx.c b/src/main/drivers/stm32/system_stm32f4xx.c
index b9cd57d09b..60e8acb0e7 100644
--- a/src/main/drivers/stm32/system_stm32f4xx.c
+++ b/src/main/drivers/stm32/system_stm32f4xx.c
@@ -147,6 +147,10 @@ bool isMPUSoftReset(void)
 
 void systemInit(void)
 {
+    persistentObjectInit();
+
+    checkForBootLoaderRequest();
+
     SetSysClock();
 
     // Configure NVIC preempt/priority groups
diff --git a/src/main/drivers/stm32/system_stm32f7xx.c b/src/main/drivers/stm32/system_stm32f7xx.c
index fd89b0c3ea..0b377c1b9a 100644
--- a/src/main/drivers/stm32/system_stm32f7xx.c
+++ b/src/main/drivers/stm32/system_stm32f7xx.c
@@ -90,6 +90,8 @@ static void checkForBootLoaderRequest(void)
 
 void systemInit(void)
 {
+    persistentObjectInit();
+
     checkForBootLoaderRequest();
 
     //  Mark ITCM-RAM as read-only
diff --git a/src/main/msc/usbd_msc_desc.c b/src/main/drivers/stm32/usbd_msc_desc.c
similarity index 100%
rename from src/main/msc/usbd_msc_desc.c
rename to src/main/drivers/stm32/usbd_msc_desc.c
diff --git a/src/main/msc/usbd_msc_desc.h b/src/main/drivers/stm32/usbd_msc_desc.h
similarity index 100%
rename from src/main/msc/usbd_msc_desc.h
rename to src/main/drivers/stm32/usbd_msc_desc.h
diff --git a/src/main/msc/usbd_storage.c b/src/main/msc/usbd_storage.c
index 11b333a176..df6e983b06 100644
--- a/src/main/msc/usbd_storage.c
+++ b/src/main/msc/usbd_storage.c
@@ -29,8 +29,10 @@
 #include "usbd_msc.h"
 #else
 #include "usbd_msc_mem.h"
+#ifndef AT32F435
 #include "usbd_msc_core.h"
 #endif
+#endif
 
 #include "usbd_storage.h"
 
diff --git a/src/main/msc/usbd_storage.h b/src/main/msc/usbd_storage.h
index e48c328fc1..c1f7d6595a 100644
--- a/src/main/msc/usbd_storage.h
+++ b/src/main/msc/usbd_storage.h
@@ -26,8 +26,10 @@
 #include "usbd_msc.h"
 #else
 #include "usbd_msc_mem.h"
+#ifndef AT32F435
 #include "usbd_msc_core.h"
 #endif
+#endif
 
 #include "common/time.h"
 
diff --git a/src/main/target/AT32F435/target.h b/src/main/target/AT32F435/target.h
index c28b56d410..167fe95669 100644
--- a/src/main/target/AT32F435/target.h
+++ b/src/main/target/AT32F435/target.h
@@ -62,6 +62,7 @@
 #define USE_I2C_DEVICE_3
 
 #define USE_USB_DETECT
+#define USE_PERSISTENT_MSC_RTC
 #define USE_VCP
 
 #define UNIFIED_SERIAL_PORT_COUNT       1
diff --git a/src/main/target/AT32F435/target.mk b/src/main/target/AT32F435/target.mk
index 1936c67c0f..c205c68465 100644
--- a/src/main/target/AT32F435/target.mk
+++ b/src/main/target/AT32F435/target.mk
@@ -1,52 +1,5 @@
-CMSIS_DIR         := $(ROOT)/lib/main/AT32F43x/cmsis
 TARGET_MCU        := AT32F435
 MCU_FLASH_SIZE    := 4032
 DEVICE_FLAGS       = -DAT32F435ZMT7
 TARGET_MCU_FAMILY := AT32F4
 
-AT_LIB_DIR      = $(ROOT)/lib/main/AT32F43x
-STDPERIPH_DIR   = $(AT_LIB_DIR)/drivers
-
-STDPERIPH_SRC   = $(notdir $(wildcard $(STDPERIPH_DIR)/src/*.c))
-
-EXCLUDES        = at32f435_437_dvp.c \
-				  at32f435_437_can.c \
-				  at32f435_437_xmc.c \
-				  at32f435_437_emac
-
-STARTUP_SRC     = at32/startup_at32f435_437.s
-STDPERIPH_SRC   := $(filter-out ${EXCLUDES}, $(STDPERIPH_SRC))
-
-VPATH           := $(VPATH):$(AT_LIB_DIR)/cmsis/cm4/core_support:$(STDPERIPH_DIR)/inc:$(SRC_DIR)/startup/at32:$(STDPERIPH_DIR)/src
-
-INCLUDE_DIRS    := $(INCLUDE_DIRS) \
-                   $(SRC_DIR)/startup/at32 \
-                   $(STDPERIPH_DIR)/inc \
-                   $(AT_LIB_DIR)/cmsis/cm4/core_support \
-                   $(AT_LIB_DIR)/cmsis/cm4 \
-                   $(AT_LIB_DIR)/middlewares/i2c_application_library \
-                   $(AT_LIB_DIR)/middlewares/usb_drivers/inc \
-                   $(AT_LIB_DIR)/middlewares/usbd_class/cdc
-
-DEVICE_STDPERIPH_SRC = $(STDPERIPH_SRC)
-
-TARGET_SRC		:= \
-            $(AT_LIB_DIR)/middlewares/i2c_application_library/i2c_application.c
-
-LD_SCRIPT       = $(LINKER_DIR)/at32_flash_f43xM.ld
-
-ARCH_FLAGS      = -std=c99  -mthumb -mcpu=cortex-m4 -march=armv7e-m -mfloat-abi=hard -mfpu=fpv4-sp-d16 -fsingle-precision-constant -Wdouble-promotion
-DEVICE_FLAGS   += -DUSE_ATBSP_DRIVER -DAT32F43x -DHSE_VALUE=$(HSE_VALUE) -DAT32 -DUSE_OTG_HOST_MODE
-
-MCU_COMMON_SRC = \
-    $(addprefix startup/at32/,$(notdir $(wildcard $(SRC_DIR)/startup/at32/*.c))) \
-    $(addprefix drivers/at32/,$(notdir $(wildcard $(SRC_DIR)/drivers/at32/*.c))) \
-    drivers/bus_i2c_timing.c \
-    drivers/pwm_output_dshot_shared.c
-
-MCU_EXCLUDES =
-
-VCP_SRC = \
-        $(addprefix $(AT_LIB_DIR)/middlewares/usbd_class/cdc/,$(notdir $(wildcard $(AT_LIB_DIR)/middlewares/usbd_class/cdc/*.c))) \
-        $(addprefix $(AT_LIB_DIR)/middlewares/usb_drivers/src/,$(notdir $(wildcard $(AT_LIB_DIR)/middlewares/usb_drivers/src/*.c))) \
-        drivers/usb_io.c