diff --git a/HAL_N_Middlewares/Inc/usbd_cdc_if.h b/HAL_N_Middlewares/Inc/usbd_cdc_if.h
index 2c9a669..88a4e86 100644
--- a/HAL_N_Middlewares/Inc/usbd_cdc_if.h
+++ b/HAL_N_Middlewares/Inc/usbd_cdc_if.h
@@ -109,7 +109,7 @@ extern "C"
   uint8_t CDC_Transmit_FS(uint8_t *Buf, uint16_t Len);
 
   /* USER CODE BEGIN EXPORTED_FUNCTIONS */
-uint8_t *CDCInitRxbufferNcallback(void (*callback)(uint32_t));
+uint8_t *CDCInitRxbufferNcallback(void (*callback)(uint32_t),void (*callback2)(uint32_t));
   /* USER CODE END EXPORTED_FUNCTIONS */
 
   /**
diff --git a/HAL_N_Middlewares/Src/freertos.c b/HAL_N_Middlewares/Src/freertos.c
index e0a893a..99e9a51 100644
--- a/HAL_N_Middlewares/Src/freertos.c
+++ b/HAL_N_Middlewares/Src/freertos.c
@@ -147,7 +147,6 @@ void StartDefaultTask(void const * argument)
 {
   /* init code for USB_DEVICE */
   USB_ResetPort(USB_OTG_FS);
-  USBD_FS_SPEED
   MX_USB_DEVICE_Init();
   /* USER CODE BEGIN StartDefaultTask */
   /* Infinite loop */
diff --git a/HAL_N_Middlewares/Src/usbd_cdc_if.c b/HAL_N_Middlewares/Src/usbd_cdc_if.c
index 3742471..69e68fd 100644
--- a/HAL_N_Middlewares/Src/usbd_cdc_if.c
+++ b/HAL_N_Middlewares/Src/usbd_cdc_if.c
@@ -50,6 +50,8 @@
 
 /* USER CODE BEGIN PRIVATE_TYPES */
 void (*transmitcpltcallback)(uint32_t);
+
+void (*receivecpltcallback)(uint32_t);
 /* USER CODE END PRIVATE_TYPES */
 
 /**
@@ -261,6 +263,10 @@ static int8_t CDC_Receive_FS(uint8_t *Buf, uint32_t *Len)
     /* USER CODE BEGIN 6 */
     USBD_CDC_SetRxBuffer(&hUsbDeviceFS, &Buf[0]);
     USBD_CDC_ReceivePacket(&hUsbDeviceFS);
+    if(receivecpltcallback != NULL)
+    {
+        receivecpltcallback(*Len);
+    }
     return (USBD_OK);
     /* USER CODE END 6 */
 }
@@ -291,9 +297,10 @@ uint8_t CDC_Transmit_FS(uint8_t *Buf, uint16_t Len)
     return result;
 }
 
-uint8_t *CDCInitRxbufferNcallback(void (*callback)(uint32_t))
+uint8_t *CDCInitRxbufferNcallback(void (*callback)(uint32_t),void (*callback2)(uint32_t))
 {
     transmitcpltcallback=callback;
+    receivecpltcallback=callback2;
     return (uint8_t *)UserRxBufferFS;
 }
 
diff --git a/bsp/usb/bsp_usb.c b/bsp/usb/bsp_usb.c
index 279a89c..aade217 100644
--- a/bsp/usb/bsp_usb.c
+++ b/bsp/usb/bsp_usb.c
@@ -1,8 +1,20 @@
+/**
+ * @file bsp_usb.c
+ * @author your name (you@domain.com)
+ * @brief usb是单例bsp,因此不保存实例
+ * @version 0.1
+ * @date 2023-02-09
+ * 
+ * @copyright Copyright (c) 2023
+ * 
+ */
+
 #include "bsp_usb.h"
 
 static uint8_t *bsp_usb_rx_buffer; // 接收到的数据会被放在这里,buffer size为2028
 // 注意usb单个数据包(Full speed模式下)最大为64byte,超出可能会出现丢包情况
 
+// 这是传输完成的回调函数,在usbd_cdc_if.c中被调用
 __weak void USBTransmitCpltCallback(uint32_t len)
 {
     // 本次发送的数据
@@ -10,12 +22,19 @@ __weak void USBTransmitCpltCallback(uint32_t len)
     // 传输完成会调用此函数,to do something
 }
 
+__weak void USBReceiveCpltCallback(uint32_t len)
+{
+    // 本次接收的数据
+    UNUSED(len);
+    // 传输完成会调用此函数,to do something
+}
+
 uint8_t *USBInit()
 {
-                                             // 上电后重新枚举usb设备
+    // 上电后重新枚举usb设备
     USBTransmit((uint8_t *)"USB DEVICE READY", sizeof("USB DEVICE READY")); // 发送初始化完成信息
-    bsp_usb_rx_buffer = CDCInitRxbufferNcallback(USBTransmitCpltCallback);                         // 获取接收数据指针
-
+    bsp_usb_rx_buffer = CDCInitRxbufferNcallback(USBTransmitCpltCallback,USBReceiveCpltCallback);  // 获取接收数据指针
+    // usb的接收回调函数会在这里被设置,并将数据保存在bsp_usb_rx_buffer中
     return bsp_usb_rx_buffer;
 }
 
@@ -23,5 +42,3 @@ void USBTransmit(uint8_t *buffer, uint16_t len)
 {
     CDC_Transmit_FS(buffer, len); // 发送
 }
-
-
diff --git a/bsp/usb/bsp_usb.h b/bsp/usb/bsp_usb.h
index de8d76d..61753b7 100644
--- a/bsp/usb/bsp_usb.h
+++ b/bsp/usb/bsp_usb.h
@@ -1,20 +1,25 @@
+/**
+ * @file bsp_usb.h
+ * @author your name (you@domain.com)
+ * @brief 提供对usb vpc(virtal com port)的操作接口,hid和msf考虑后续添加
+ * @todo 与usart的接口统一完成兼容
+ * @attention 这一版修改了usbd_cdc_if.c中的CDC_Receive_FS函数,cube生成后会被覆盖.后续需要由usbcdciftemplate创建一套自己的模板
+ * @version 0.1
+ * @date 2023-02-09
+ * 
+ * @copyright Copyright (c) 2023
+ * 
+ */
+
 #include "usb_device.h"
 #include "usbd_cdc.h"
 #include "usbd_conf.h"
 #include "usbd_desc.h"
 #include "usbd_cdc_if.h"
 
-typedef enum
-{
-    USB_CONNECTION_RAWDATA = 0,
-    USB_CONNECTION_VOFA,
-    USB_CONNECTION_SEASKY,
-} USB_Connection_Type_e; // 选择usb连接模式,默认为原始数据
-// 方便调试,也可以不用
-
 /* @note 虚拟串口的波特率/校验位/数据位等动态可变,取决于上位机的设定 */
 /* 使用时不需要关心这些设置(作为从机) */
 
 uint8_t *USBInit(); // bsp初始化时调用会重新枚举设备
 
-void USBTransmit(uint8_t *buffer, uint16_t len); // 通过usb发送数据
\ No newline at end of file
+void USBTransmit(uint8_t *buffer, uint16_t len); // 通过usb发送数据