基于STM32CubeIDE 开发 FATFS + SD卡 + USB 的读卡器功能
一、介绍
本次采用STM32CubeIDE 平台 STM32L476RE 芯片 自带 usb接口和 Mirco卡槽，实现通过USB连接电脑能正确对SD卡中的文件进行读写操作，同时芯片内部程序也可以以FATFS方式对SD卡操作。
二、步骤
1、RCC SYS 配置比较简单，大家都知道
2、USB_OTG_FS配置
以从机的方式配置，Mode ：Device_Only
Activate VBUS: VBUS sensing 这里我们检测vbus状态，避免 PC和芯片同时对一个文件访问产生冲突
其他默认 
3、USB_DEVICE 配置
Mode：选择Mass Storage Class 即MSC 大容量存储设备类
4、FATFS 配置
使用SD Card 其他默认就好
5、 SDMMC 配置
总线4位宽 使能硬件流控制 时钟分频设置
开启DMA 中断
开启DMA
配置GPIO
6堆栈设置
7 main函数增加 fatfs 测试函数 测试正常读写文件功能
对于想具体了解 USB相关的库函数大家可以参考最后相关链接，我把有关USB所有文档打包上传了。
static void FS_FileOperations_LIUYAN(void)
{
FRESULT res; /* FatFs function common result code */
uint32_t byteswritten, bytesread; /* File write/read counts */
uint8_t wtext[] = "stm32l476g_eval : This is STM32 working with FatFs and uSD diskio driver"; /* File write buffer */
uint8_t rtext[100]; /* File read buffer */
/* Register the file system object to the FatFs module */
if(f_mount(&SDFatFs, (TCHAR const*)SDPath, 0) == FR_OK)
{
/* Create and Open a new text file object with write access */
if(f_open(&MyFile, "liuyan.TXT", FA_CREATE_ALWAYS | FA_WRITE) == FR_OK)
{
/* Write data to the text file */
res = f_write(&MyFile, wtext, sizeof(wtext), (void *)&byteswritten);
if((byteswritten > 0) && (res == FR_OK))
{
/* Close the open text file */
f_close(&MyFile);
/* Open the text file object with read access */
//f_mount(NULL, (TCHAR const*)SDPath, 0);
}
}
}
/* Error */
Error_Handler();
}
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_DMA_Init();
MX_USB_DEVICE_Init();
MX_SDMMC1_SD_Init();
MX_FATFS_Init();
/* USER CODE BEGIN 2 */
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
if(HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_9) == 0)
{
FS_FileOperations_LIUYAN();
}
}
/* USER CODE END 3 */
}
8 修改USB 接口函数 就是 usbd_storage_if.c 文件
大家有想了解usb相关的文档，我已打包发布出来，有需要的可以下载
usbd_storage_if.c 代码如下：
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : usbd_storage_if.c
* @version : v2.0_Cube
* @brief : Memory management layer.
******************************************************************************
* @attention
*
* © Copyright (c) 2020 STMicroelectronics.
* All rights reserved.
*
* This software component is licensed by ST under Ultimate Liberty license
* SLA0044, the "License"; You may not use this file except in compliance with
* the License. You may obtain a copy of the License at:
* www.st.com/SLA0044
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "usbd_storage_if.h"
/* USER CODE BEGIN INCLUDE */
#include "bsp_driver_sd.h"
/* USER CODE END INCLUDE */
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PV */
/* Private variables ---------------------------------------------------------*/
__IO uint32_t writestatus, readstatus = 0;
/* USER CODE END PV */
/** @addtogroup STM32_USB_OTG_DEVICE_LIBRARY
* @brief Usb device.
* @{
*/
/** @defgroup USBD_STORAGE
* @brief Usb mass storage device module
* @{
*/
/** @defgroup USBD_STORAGE_Private_TypesDefinitions
* @brief Private types.
* @{
*/
/* USER CODE BEGIN PRIVATE_TYPES */
/* USER CODE END PRIVATE_TYPES */
/**
* @}
*/
/** @defgroup USBD_STORAGE_Private_Defines
* @brief Private defines.
* @{
*/
#define STORAGE_LUN_NBR 1
#define STORAGE_BLK_NBR 0x10000
#define STORAGE_BLK_SIZ 0x200
/* USER CODE BEGIN PRIVATE_DEFINES */
/* USER CODE END PRIVATE_DEFINES */
/**
* @}
*/
/** @defgroup USBD_STORAGE_Private_Macros
* @brief Private macros.
* @{
*/
/* USER CODE BEGIN PRIVATE_MACRO */
/* USER CODE END PRIVATE_MACRO */
/**
* @}
*/
/** @defgroup USBD_STORAGE_Private_Variables
* @brief Private variables.
* @{
*/
/* USER CODE BEGIN INQUIRY_DATA_FS */
/** USB Mass storage Standard Inquiry Data. */
const int8_t STORAGE_Inquirydata_FS[] = {/* 36 */
/* LUN 0 */
0x00,
0x80,
0x02,
0x02,
(STANDARD_INQUIRY_DATA_LEN - 5),
0x00,
0x00,
0x00,
'S', 'T', 'M', ' ', ' ', ' ', ' ', ' ', /* Manufacturer : 8 bytes */
'P', 'r', 'o', 'd', 'u', 'c', 't', ' ', /* Product : 16 Bytes */
' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ',
'0', '.', '0' ,'1' /* Version : 4 Bytes */
};
/* USER CODE END INQUIRY_DATA_FS */
/* USER CODE BEGIN PRIVATE_VARIABLES */
/* USER CODE END PRIVATE_VARIABLES */
/**
* @}
*/
/** @defgroup USBD_STORAGE_Exported_Variables
* @brief Public variables.
* @{
*/
extern USBD_HandleTypeDef hUsbDeviceFS;
/* USER CODE BEGIN EXPORTED_VARIABLES */
extern SD_HandleTypeDef hsd1;
/* USER CODE END EXPORTED_VARIABLES */
/**
* @}
*/
/** @defgroup USBD_STORAGE_Private_FunctionPrototypes
* @brief Private functions declaration.
* @{
*/
static int8_t STORAGE_Init_FS(uint8_t lun);
static int8_t STORAGE_GetCapacity_FS(uint8_t lun, uint32_t *block_num, uint16_t *block_size);
static int8_t STORAGE_IsReady_FS(uint8_t lun);
static int8_t STORAGE_IsWriteProtected_FS(uint8_t lun);
static int8_t STORAGE_Read_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len);
static int8_t STORAGE_Write_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len);
static int8_t STORAGE_GetMaxLun_FS(void);
/* USER CODE BEGIN PRIVATE_FUNCTIONS_DECLARATION */
/* USER CODE END PRIVATE_FUNCTIONS_DECLARATION */
/**
* @}
*/
USBD_StorageTypeDef USBD_Storage_Interface_fops_FS =
{
STORAGE_Init_FS,
STORAGE_GetCapacity_FS,
STORAGE_IsReady_FS,
STORAGE_IsWriteProtected_FS,
STORAGE_Read_FS,
STORAGE_Write_FS,
STORAGE_GetMaxLun_FS,
(int8_t *)STORAGE_Inquirydata_FS
};
/* Private functions ---------------------------------------------------------*/
/**
* @brief Initializes over USB FS IP
* @param lun:
* @retval USBD_OK if all operations are OK else USBD_FAIL
*/
int8_t STORAGE_Init_FS(uint8_t lun)
{
/* USER CODE BEGIN 2 */
BSP_SD_Init();
return (USBD_OK);
/* USER CODE END 2 */
}
/**
* @brief .
* @param lun: .
* @param block_num: .
* @param block_size: .
* @retval USBD_OK if all operations are OK else USBD_FAIL
*/
int8_t STORAGE_GetCapacity_FS(uint8_t lun, uint32_t *block_num, uint16_t *block_size)
{
/* USER CODE BEGIN 3 */
HAL_SD_CardInfoTypeDef info;
int8_t ret = -1;
if(BSP_SD_IsDetected() != SD_NOT_PRESENT)
{
BSP_SD_GetCardInfo(&info);
*block_num = info.LogBlockNbr - 1;
*block_size = info.LogBlockSize;
ret = 0;
}
return ret;
/* USER CODE END 3 */
}
/**
* @brief .
* @param lun: .
* @retval USBD_OK if all operations are OK else USBD_FAIL
*/
int8_t STORAGE_IsReady_FS(uint8_t lun)
{
/* USER CODE BEGIN 4 */
static int8_t prev_status = 0;
int8_t ret = -1;
if(BSP_SD_IsDetected() != SD_NOT_PRESENT)
{
if(prev_status < 0)
{
BSP_SD_Init();
prev_status = 0;
}
if(BSP_SD_GetCardState() == SD_TRANSFER_OK)
{
ret = 0;
}
}
else if(prev_status == 0)
{
prev_status = -1;
}
return ret;
/* USER CODE END 4 */
}
/**
* @brief .
* @param lun: .
* @retval USBD_OK if all operations are OK else USBD_FAIL
*/
int8_t STORAGE_IsWriteProtected_FS(uint8_t lun)
{
/* USER CODE BEGIN 5 */
return (USBD_OK);
/* USER CODE END 5 */
}
/**
* @brief .
* @param lun: .
* @retval USBD_OK if all operations are OK else USBD_FAIL
*/
int8_t STORAGE_Read_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len)
{
/* USER CODE BEGIN 6 */
int8_t ret = -1;
uint32_t timeout = 100000;
BSP_SD_ReadBlocks((uint32_t *)buf, blk_addr, blk_len, SD_DATATIMEOUT);
while(BSP_SD_GetCardState() != SD_TRANSFER_OK)
{
if (timeout-- == 0)
{
return ret;
}
}
ret = 0;
return ret;
/* USER CODE END 6 */
}
/**
* @brief .
* @param lun: .
* @retval USBD_OK if all operations are OK else USBD_FAIL
*/
int8_t STORAGE_Write_FS(uint8_t lun, uint8_t *buf, uint32_t blk_addr, uint16_t blk_len)
{
/* USER CODE BEGIN 7 */
int8_t ret = -1;
uint32_t timeout = 100000;
BSP_SD_WriteBlocks((uint32_t *)buf, blk_addr, blk_len, SD_DATATIMEOUT);
while(BSP_SD_GetCardState() != SD_TRANSFER_OK)
{
if (timeout-- == 0)
{
return ret;
}
}
ret = 0;
return ret;
/* USER CODE END 7 */
}
/**
* @brief .
* @param None
* @retval .
*/
int8_t STORAGE_GetMaxLun_FS(void)
{
/* USER CODE BEGIN 8 */
return (STORAGE_LUN_NBR - 1);
/* USER CODE END 8 */
}
/* USER CODE BEGIN PRIVATE_FUNCTIONS_IMPLEMENTATION */
//void BSP_SD_WriteCpltCallback(void)
//{
// writestatus = 1;
//}
//
//void BSP_SD_ReadCpltCallback(void)
//{
// readstatus = 1;
//}
/* USER CODE END PRIVATE_FUNCTIONS_IMPLEMENTATION */
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
9 程序通过检测Vbus 电平状态来确认是否插入PC 机，正常在插入PC 时，程序不允许对SD卡操作
三、结果
最后文章参考博主 http://www.freesion.com/article/489386717/
本例程所有代码链接： https://download.csdn.net/download/weixin_39949884/12256206
USB 所有资源打包地址： https://download.csdn.net/download/weixin_39949884/12274629