f_mount() returns FA_DISK_ERR - stm32

Question

I have made few changes in my source code after suggestion form everyone.For connecting FATFS API with SPI interface i have followed this code..
https://github.com/eziya/STM32_SPI_SDCARD/blob/master/Src/fatfs_sd.c
and changed my user_diskio.c accordingly.
After doing all those things then also my SD Card returns FA_DISK_ERROR.
I have changed SD Card slot as well as SD Card. But nothing Changed.
My user_diskio.c look like this:
#include <string.h>
#include "ff_gen_drv.h"
#include "fatfs_sd.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Disk status */
static volatile DSTATUS Stat = STA_NOINIT;
/* USER CODE END DECL */
/* Private function prototypes -----------------------------------------------*/
DSTATUS USER_initialize (BYTE pdrv);
DSTATUS USER_status (BYTE pdrv);
DRESULT USER_read (BYTE pdrv, BYTE *buff, DWORD sector, UINT count);
#if _USE_WRITE == 1
DRESULT USER_write (BYTE pdrv, const BYTE *buff, DWORD sector, UINT count);
#endif /* _USE_WRITE == 1 */
#if _USE_IOCTL == 1
DRESULT USER_ioctl (BYTE pdrv, BYTE cmd, void *buff);
#endif /* _USE_IOCTL == 1 */
Diskio_drvTypeDef USER_Driver =
{
USER_initialize,
USER_status,
USER_read,
#if _USE_WRITE
USER_write,
#endif /* _USE_WRITE == 1 */
#if _USE_IOCTL == 1
USER_ioctl,
#endif /* _USE_IOCTL == 1 */
};
/* Private functions ---------------------------------------------------------*/
/**
* #brief Initializes a Drive
* #param pdrv: Physical drive number (0..)
* #retval DSTATUS: Operation status
*/
DSTATUS USER_initialize (
BYTE pdrv /* Physical drive nmuber to identify the drive */
)
{
/* USER CODE BEGIN INIT */
return SD_disk_initialize(pdrv);
/* USER CODE END INIT */
}
/**
* #brief Gets Disk Status
* #param pdrv: Physical drive number (0..)
* #retval DSTATUS: Operation status
*/
DSTATUS USER_status (
BYTE pdrv /* Physical drive number to identify the drive */
)
{
/* USER CODE BEGIN STATUS */
return SD_disk_status(pdrv);
/* USER CODE END STATUS */
}
/**
* #brief Reads Sector(s)
* #param pdrv: Physical drive number (0..)
* #param *buff: Data buffer to store read data
* #param sector: Sector address (LBA)
* #param count: Number of sectors to read (1..128)
* #retval DRESULT: Operation result
*/
DRESULT USER_read (
BYTE pdrv, /* Physical drive nmuber to identify the drive */
BYTE *buff, /* Data buffer to store read data */
DWORD sector, /* Sector address in LBA */
UINT count /* Number of sectors to read */
)
{
/* USER CODE BEGIN READ */
return SD_disk_read(pdrv, buff, sector, count);
/* USER CODE END READ */
}
/**
* #brief Writes Sector(s)
* #param pdrv: Physical drive number (0..)
* #param *buff: Data to be written
* #param sector: Sector address (LBA)
* #param count: Number of sectors to write (1..128)
* #retval DRESULT: Operation result
*/
#if _USE_WRITE == 1
DRESULT USER_write (
BYTE pdrv, /* Physical drive nmuber to identify the drive */
const BYTE *buff, /* Data to be written */
DWORD sector, /* Sector address in LBA */
UINT count /* Number of sectors to write */
)
{
/* USER CODE BEGIN WRITE */
/* USER CODE HERE */
return SD_disk_write(pdrv, buff, sector, count);
/* USER CODE END WRITE */
}
#endif /* _USE_WRITE == 1 */
/**
* #brief I/O control operation
* #param pdrv: Physical drive number (0..)
* #param cmd: Control code
* #param *buff: Buffer to send/receive control data
* #retval DRESULT: Operation result
*/
#if _USE_IOCTL == 1
DRESULT USER_ioctl (
BYTE pdrv, /* Physical drive nmuber (0..) */
BYTE cmd, /* Control code */
void *buff /* Buffer to send/receive control data */
)
{
/* USER CODE BEGIN IOCTL */
return SD_disk_ioctl(pdrv, cmd, buff);
/* USER CODE END IOCTL */
}
#endif /* _USE_IOCTL == 1 */
and fatfs_sd.c looks like this:
GO TO THE ABOVE GITHUB LINK
Have no idea where i am going wrong.
Anything on this topic will be helpful.
Thanks in advance.

Answer 1

I've written my own driver using an stm32f7 chip for FatFS before and think I might know what's going on. My guess is that you likely forgot to attach implementations for the disk_write and disk_read functions in diskio.h. Without doing that, the FatFS library has no clue on how to actually interface with the SD card.
You could check out the FatFS documentation/manual as a general resource: here
Pay very close attention to the "Required Functions" section in this app note: here
An example project like yours but for STM32F4: here