stm32 Fatfs 读写SD卡

#include “common.h”
/———————————————————————–/
/ Inidialize a Drive                                                    /

DSTATUS disk_initialize (
    BYTE drv                / Physical drive nmuber (0..) /
)
{
    u8 state;

    if(drv)
    {
        return STA_NOINIT;  //仅支持磁盘0的操作
    }

    state = SD_Init();
    if(state == STA_NODISK)
    {
        return STA_NODISK;
    }
    else if(state != 0)
    {
        return STA_NOINIT;  //其他错误：初始化失败
    }
    else
    {
        return 0;           //初始化成功
    }
}

/———————————————————————–/
/ Return Disk Status                                                    /

DSTATUS disk_status (
    BYTE drv        / Physical drive nmuber (0..) /
)
{
    if(drv)
    {
        return STA_NOINIT;  //仅支持磁盘0操作
    }

    //检查SD卡是否插入
    if(!SD_DET())
    {
        return STA_NODISK;
    }
    return 0;
}

/———————————————————————–/
/ Read Sector(s)                                                        /

DRESULT disk_read (
    BYTE drv,        / Physical drive nmuber (0..) /
    BYTE buff,        / Data buffer to store read data /
    DWORD sector,    / Sector address (LBA) /
    BYTE count        / Number of sectors to read (1..255) /
)
{
    u8 res=0;
    if (drv || !count)
    {
        return RES_PARERR;  //仅支持单磁盘操作，count不能等于0，否则返回参数错误
    }
    if(!SD_DET())
    {
        return RES_NOTRDY;  //没有检测到SD卡，报NOT READY错误
    }

    if(count==1)            //1个sector的读操作
    {
        res = SD_ReadSingleBlock(sector, buff);
    }
    else                    //多个sector的读操作
    {
        res = SD_ReadMultiBlock(sector, buff, count);
    }
    /
    do
    {
        if(SD_ReadSingleBlock(sector, buff)!=0)
        {
            res = 1;
            break;
        }
        buff+=512;
    }while(–count);                                         
    /
    //处理返回值，将SPI_SD_driver.c的返回值转成ff.c的返回值
    if(res == 0x00)
    {
        return RES_OK;
    }
    else
    {
        return RES_ERROR;
    }
}

/———————————————————————–/
/ Write Sector(s)                                                       /

#if _READONLY == 0
DRESULT disk_write (
    BYTE drv,            / Physical drive nmuber (0..) /
    const BYTE buff,    / Data to be written /
    DWORD sector,        / Sector address (LBA) /
    BYTE count            / Number of sectors to write (1..255) /
)
{
    u8 res;

    if (drv || !count)
    {
        return RES_PARERR;  //仅支持单磁盘操作，count不能等于0，否则返回参数错误
    }
    if(!SD_DET())
    {
        return RES_NOTRDY;  //没有检测到SD卡，报NOT READY错误
    }

    // 读写操作
    if(count == 1)
    {
        res = SD_WriteSingleBlock(sector, buff);
    }
    else
    {
        res = SD_WriteMultiBlock(sector, buff, count);
    }
    // 返回值转换
    if(res == 0)
    {
        return RES_OK;
    }
    else
    {
        return RES_ERROR;
    }
}
#endif / _READONLY /

/———————————————————————–/
/ Miscellaneous Functions                                               /

DRESULT disk_ioctl (
    BYTE drv,        / Physical drive nmuber (0..) /
    BYTE ctrl,        / Control code /
    void buff        / Buffer to send/receive control data /
)
{
    DRESULT res;

    if (drv)
    {
        return RES_PARERR;  //仅支持单磁盘操作，否则返回参数错误
    }

    //FATFS目前版本仅需处理CTRL_SYNC，GET_SECTOR_COUNT，GET_BLOCK_SIZ三个命令
    switch(ctrl)
    {
    case CTRL_SYNC:
        SD_CS_ENABLE();
        if(SD_WaitReady()==0)
        {
            res = RES_OK;
        }
        else
        {
            res = RES_ERROR;
        }
        SD_CS_DISABLE();
        break;

    case GET_BLOCK_SIZE:
        (WORD)buff = 512;
        res = RES_OK;
        break;

    case GET_SECTOR_COUNT:
        (DWORD)buff = SD_GetCapacity();
        res = RES_OK;
        break;
    default:
        res = RES_PARERR;
        break;
    }

    return res;
}

/———————————————————————–/
/ User defined function to give a current time to fatfs module          /
/ 31-25: Year(0-127 org.1980), 24-21: Month(1-12), 20-16: Day(1-31) /
/ 15-11: Hour(0-23), 10-5: Minute(0-59), 4-0: Second(0-29 2) /
DWORD get_fattime (void)
{
  return 0;
}