diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/board.c b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/board.c
index de55bbf25..68473e72e 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/board.c
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/board.c
@@ -71,21 +71,35 @@ void SystemClockConfig(void)
     (void)CLK_XtalInit(&stcXtalInit);
 
     (void)CLK_PLLStructInit(&stcPLLHInit);
-    /* VCO = (8/1)*100 = 800MHz*/
+
     stcPLLHInit.u8PLLState      = CLK_PLL_ON;
     stcPLLHInit.PLLCFGR         = 0UL;
     stcPLLHInit.PLLCFGR_f.PLLM  = 1UL - 1UL;
+
+#ifdef BSP_USING_USB
+    /* VCO = (8/1)*120 = 960MHz*/
+    stcPLLHInit.PLLCFGR_f.PLLN  = 120UL - 1UL;
+#else
+    /* VCO = (8/1)*100 = 800MHz*/
     stcPLLHInit.PLLCFGR_f.PLLN  = 100UL - 1UL;
+#endif
     stcPLLHInit.PLLCFGR_f.PLLP  = 4UL - 1UL;
     stcPLLHInit.PLLCFGR_f.PLLQ  = 4UL - 1UL;
     stcPLLHInit.PLLCFGR_f.PLLR  = 4UL - 1UL;
     stcPLLHInit.PLLCFGR_f.PLLSRC = CLK_PLL_SRC_XTAL;
     (void)CLK_PLLInit(&stcPLLHInit);
 
+#ifdef BSP_USING_USB
+    /* Highspeed SRAM set to 0 Read/Write wait cycle */
+    SRAM_SetWaitCycle(SRAM_SRAMH, SRAM_WAIT_CYCLE0, SRAM_WAIT_CYCLE0);
+    /* SRAM1_2_3_4_backup set to 1 Read/Write wait cycle */
+    SRAM_SetWaitCycle((SRAM_SRAM123 | SRAM_SRAM4 | SRAM_SRAMB), SRAM_WAIT_CYCLE1, SRAM_WAIT_CYCLE1);
+#else
     /* Highspeed SRAM set to 1 Read/Write wait cycle */
     SRAM_SetWaitCycle(SRAM_SRAMH, SRAM_WAIT_CYCLE1, SRAM_WAIT_CYCLE1);
     /* SRAM1_2_3_4_backup set to 2 Read/Write wait cycle */
     SRAM_SetWaitCycle((SRAM_SRAM123 | SRAM_SRAM4 | SRAM_SRAMB), SRAM_WAIT_CYCLE2, SRAM_WAIT_CYCLE2);
+#endif
     /* 0-wait @ 40MHz */
     EFM_SetWaitCycle(EFM_WAIT_CYCLE5);
     /* 4 cycles for 200 ~ 250MHz */
diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/sdio/Kconfig b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/sdio/Kconfig
index 0d1f4f779..05f09c07a 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/sdio/Kconfig
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/sdio/Kconfig
@@ -12,13 +12,13 @@ if BSP_USING_SDIO
         default "sdio_dev"
 
     config MOUNT_SDCARD_FS
-        bool "mount sd card file system"
+        bool "mount sd card file system : if y then not support usb-mount-fs"
         default y
         select MOUNT_SDCARD
 
     if MOUNT_SDCARD_FS
         config MOUNT_SDCARD_FS_TYPE
-            int "choose file system type : FATFS(0) LWEXT4(3)"
+            int "choose file system type : FATFS(0)"
             default 0 
     endif
 endif
diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/Kconfig b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/Kconfig
index 65894670c..cebb2f422 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/Kconfig
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/Kconfig
@@ -11,5 +11,15 @@ config BSP_USING_HC32_USBH
         config USB_DEVICE_NAME
             string "usb bus device name"
             default "usb_dev"
+        config MOUNT_USB_FS
+            bool "mount usb file system : if y then not support sdcard-mount-fs"
+            default y
+            select MOUNT_USB
+
+        if MOUNT_USB_FS
+            config MOUNT_USB_FS_TYPE
+                int "choose file system type : FATFS(0)"
+                default 0 
+        endif
     endif
 
diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/connect_usb.c b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/connect_usb.c
index 523e6839a..3c1853b10 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/connect_usb.c
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/connect_usb.c
@@ -35,6 +35,8 @@ Modification:
 usb_core_instance usb_app_instance;
 USBH_HOST usb_app_host;
 
+static void UsbHostTask(void *parameter);
+
 #if defined(FS_VFS)
 void UsbMountFileSystem()
 {
@@ -48,6 +50,23 @@ void UsbUnmountFileSystem()
 {
     UnmountFileSystem(UDISK_MOUNTPOINT);
 }
+
+#ifdef MOUNT_USB
+int MountUsb(void)
+{
+    int32 usb_host_task = 0;
+    usb_host_task = KTaskCreate("usbh", UsbHostTask, NONE,
+                           USB_HOST_STACK_SIZE, 8);
+    if(usb_host_task < 0) {		
+		KPrintf("usb_host_task create failed ...%s %d.\n", __FUNCTION__, __LINE__);
+		return ERROR;
+	}
+
+    StartupKTask(usb_host_task);
+
+    return 0;
+}
+#endif
 #endif
 
 static uint32 UsbHostOpen(void *dev)
@@ -127,8 +146,9 @@ static const struct UsbDevDone dev_done =
     .read = UsbHostRead,
 };
 
-static void UsbHostTask(void* parameter)
+static void UsbHostTask(void *parameter)
 {
+    usb_host_init(&usb_app_instance, &usb_app_host, &USBH_MSC_cb, &USR_cb);
     while (1) {
         usb_host_mainprocess(&usb_app_instance, &usb_app_host);
     }
@@ -191,7 +211,6 @@ static int BoardUsbDevBend(void)
 int HwUsbHostInit(void)
 {
     x_err_t ret = EOK;
-    int32 usb_host_task = 0;
 
     static struct UsbBus usb_bus;
     memset(&usb_bus, 0, sizeof(struct UsbBus));
@@ -199,8 +218,6 @@ int HwUsbHostInit(void)
     static struct UsbDriver usb_driver;
     memset(&usb_driver, 0, sizeof(struct UsbDriver));
 
-    usb_host_init(&usb_app_instance, &usb_app_host, &USBH_MSC_cb, &USR_cb);
-
     ret = BoardUsbBusInit(&usb_bus, &usb_driver);
     if (EOK != ret) {
         KPrintf("BoardUsbBusInit error ret %u\n", ret);
@@ -213,15 +230,6 @@ int HwUsbHostInit(void)
         return ERROR;
     }
 
-    usb_host_task = KTaskCreate("usbh", UsbHostTask, NONE,
-                           USB_HOST_STACK_SIZE, 8);
-    if(usb_host_task < 0) {		
-		KPrintf("usb_host_task create failed ...%s %d.\n", __FUNCTION__, __LINE__);
-		return ERROR;
-	}
-
-    StartupKTask(usb_host_task);
-
     return ret;
 }
 
diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_bsp.c b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_bsp.c
index 03698dc26..7e4f4c981 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_bsp.c
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_bsp.c
@@ -74,10 +74,6 @@ void usb_bsp_init(usb_core_instance *pdev)
 {
     stc_gpio_init_t stcGpioCfg;
 
-    /* SysTick configuration */
-    (void)SysTick_Init(1000U);
-    NVIC_SetPriority(SysTick_IRQn, DDL_IRQ_PRIO_14);
-
     /* USB clock source configurate */
     CLK_SetUSBClockSrc(CLK_USBCLK_SYSCLK_DIV5);
 
@@ -88,11 +84,6 @@ void usb_bsp_init(usb_core_instance *pdev)
     (void)GPIO_Init(USB_DM_PORT, USB_DM_PIN, &stcGpioCfg);
     (void)GPIO_Init(USB_DP_PORT, USB_DP_PIN, &stcGpioCfg);
 
-    // stcGpioInit.u16PinState = PIN_STAT_RST;
-    // stcGpioInit.u16PinDir = PIN_DIR_OUT;
-    // (void)GPIO_Init(USB_DRVVBUS_PORT, USB_DRVVBUS_PIN, &stcGpioInit);
-    // GPIO_SetPins(USB_DRVVBUS_PORT, USB_DRVVBUS_PIN);
-
     GPIO_SetFunc(USB_DRVVBUS_PORT, USB_DRVVBUS_PIN, GPIO_FUNC_10); /* VBUS */
 
     FCG_Fcg1PeriphClockCmd(FCG1_PERIPH_USBFS, ENABLE);
@@ -133,7 +124,7 @@ void usb_udelay(const uint32_t usec)
 
 void usb_mdelay(const uint32_t msec)
 {
-    SysTick_Delay(msec);
+    usb_udelay(msec * 1000);
 }
 
 /**
@@ -141,7 +132,7 @@ void usb_mdelay(const uint32_t msec)
  * @param  [in] pdev        device instance
  * @retval None
  */
-void  usb_bsp_cfgvbus(LL_USB_TypeDef *USBx)
+void usb_bsp_cfgvbus(LL_USB_TypeDef *USBx)
 {
 }
 
diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.c b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.c
index 97ffb8d8b..3026c0bd6 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.c
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.c
@@ -107,7 +107,7 @@ void usb_host_deinit(usb_core_instance *pdev, USBH_HOST *phost)
  * @param  [in] phost       host state set
  * @retval None
  */
-int usb_host_mainprocess(usb_core_instance *pdev, USBH_HOST *phost)
+void usb_host_mainprocess(usb_core_instance *pdev, USBH_HOST *phost)
 {
     __IO HOST_STATUS tmp_status;
     tmp_status = HSTATUS_FAIL;
@@ -193,8 +193,6 @@ int usb_host_mainprocess(usb_core_instance *pdev, USBH_HOST *phost)
     } else {
         ;
     }
-
-    return 0;
 }
 
 /**
diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.h b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.h
index 788f7090d..66c045fbe 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.h
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_lib/host_core/usb_host_core.h
@@ -73,7 +73,7 @@ extern void usb_host_init(usb_core_instance *pdev,
                           usb_host_class_callback_func *class_cbk,
                           usb_host_user_callback_func *user_cbk);
 extern void usb_host_deinit(usb_core_instance *pdev, USBH_HOST *phost);
-extern int usb_host_mainprocess(usb_core_instance *pdev, USBH_HOST *phost);
+extern void usb_host_mainprocess(usb_core_instance *pdev, USBH_HOST *phost);
 extern void usb_host_errorprocess(USBH_HOST *phost, HOST_STATUS errType);
 
 /**
diff --git a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_user.c b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_user.c
index 5cb3ad369..d3ceadb1f 100644
--- a/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_user.c
+++ b/Ubiquitous/XiZi_IIoT/board/hc32f4a0/third_party_driver/usb/hc32_usb_driver/usb_host_user.c
@@ -105,6 +105,7 @@ usb_host_user_callback_func USR_cb = {
 /*******************************************************************************
  * Local function prototypes ('static')
  ******************************************************************************/
+static int usb_connect_status = 0;
 
 /*******************************************************************************
  * Local variable definitions ('static')
@@ -125,7 +126,7 @@ void host_user_init(void)
 
     if (startup == 0U) {
         startup = 1U;
-        KPrintf("USB Host library v2.1.0 started\r\n");
+        //KPrintf("USB Host library v2.1.0 started\r\n");
     }
 }
 
@@ -137,7 +138,6 @@ void host_user_init(void)
 void host_user_devattached(void)
 {
     KPrintf("USB device attached\r\n");
-    UsbMountFileSystem();
 }
 
 /**
@@ -158,6 +158,7 @@ void host_user_unrecoverederror(void)
 void host_user_devdisconn(void)
 {
     KPrintf("USB device disconnect\r\n");
+    usb_connect_status = 0;
     UsbUnmountFileSystem();
 }
 
@@ -307,6 +308,12 @@ void host_user_overcurrent(void)
  */
 int host_user_msc_app(void)
 {
+    if (0 == usb_connect_status) {
+        KPrintf("ready to mount file system\n");
+        UsbMountFileSystem();
+        usb_connect_status = 1;
+    }
+    
     return ((int)0);
 }