FATFS文件系统-SD卡

apleilx · 发表于 2017-6-9 17:13:38

这两天调了下SD卡，以前没用过这玩意儿，查了好多资料，现在基本理清了SD卡相关的概念和使用方法，先移植一个FATFS文件系统测试下，可以实现正常的文件读写了。

工程用了点ST32F4的外设文件，正好研究了下GD固件库和ST固件库共存的问题。大体的思路是不要让GD的头文件和ST的头文件出现在同一个c文件中，另外ST的外设编号是从1开始，GD是0开始，使用的时候要错下位。比如用GD的SPI3，要用ST的SPI4来操作。

完成fatfs读写文件主要是改写diskio.c中的硬件接口函数以及SD卡的底层操作函数。

代码清单：
sd_lpc.h

/**************************************************************************//**
* @file sd.h
* @brief Header file for sd.c
* @version 1.0
* @date 18. Nov. 2010
*
* @note
* Copyright (C) 2010 NXP Semiconductors(NXP), ChaN.
* All rights reserved.
*
******************************************************************************/
#ifndef __SD_LPC_H
#define __SD_LPC_H
#include "stdint.h"
/* type defintion */
typedef unsigned char SD_BOOL;
#define SD_TRUE 1
#define SD_FALSE 0
#ifndef NULL
#ifdef __cplusplus // EC++
#define NULL 0
#else
#define NULL ((void *) 0)
#endif
#endif
/* Memory card type definitions */
#define CARDTYPE_UNKNOWN 0
#define CARDTYPE_MMC 1 /* MMC */
#define CARDTYPE_SDV1 2 /* V1.x Standard Capacity SD card */
#define CARDTYPE_SDV2_SC 3 /* V2.0 or later Standard Capacity SD card */
#define CARDTYPE_SDV2_HC 4 /* V2.0 or later High/eXtended Capacity SD card */
/* SD/MMC card configuration */
typedef struct tagCARDCONFIG
{
uint32_t sectorsize; /* size (in byte) of each sector, fixed to 512bytes */
uint32_t sectorcnt; /* total sector number */
uint32_t blocksize; /* erase block size in unit of sector */
uint8_t ocr[4]; /* OCR */
uint8_t cid[16]; /* CID */
uint8_t csd[16]; /* CSD */
uint8_t status[64]; /* Status */
} CARDCONFIG;
/* Public variables */
extern uint8_t CardType;
extern CARDCONFIG CardConfig;
/* Public functions */
SD_BOOL FS_SD_Init(void);
SD_BOOL SD_ReadSector (uint32_t sect, uint8_t *buf, uint32_t cnt);
SD_BOOL SD_WriteSector (uint32_t sect, const uint8_t *buf, uint32_t cnt);
SD_BOOL SD_ReadConfiguration (void);
uint8_t SD_SendCommand (uint8_t cmd, uint32_t arg, uint8_t *buf, uint32_t len);
uint8_t SD_SendACommand (uint8_t cmd, uint32_t arg, uint8_t *buf, uint32_t len);
SD_BOOL SD_RecvDataBlock (uint8_t *buf, uint32_t len);
SD_BOOL SD_SendDataBlock (const uint8_t *buf, uint8_t tkn, uint32_t len) ;
SD_BOOL SD_WaitForReady (void);
#endif // __SD_LPC_H
/* --------------------------------- End Of File ------------------------------ */

复制代码

sd_lpc.c

/**************************************************************************//**
* @file sd.c
* @brief Drivers for SD/MMC/SDHC
* @version 1.0
* @date 18. Nov. 2010
*
* @note
* Card initilization flow and some code snippets are inspired from ChaN.
*
******************************************************************************/
#include "stm32f4xx_conf.h"
#include "sd_lpc.h"
#include "diskio.h"
#define SD_SPI SPI4
/* Command definitions in SPI bus mode */
#define GO_IDLE_STATE 0
#define SEND_OP_COND 1
#define SWITCH_FUNC 6
#define SEND_IF_COND 8
#define SEND_CSD 9
#define SEND_CID 10
#define STOP_TRANSMISSION 12
#define SEND_STATUS 13
#define SET_BLOCKLEN 16
#define READ_SINGLE_BLOCK 17
#define READ_MULTIPLE_BLOCK 18
#define WRITE_SINGLE_BLOCK 24
#define WRITE_MULTIPLE_BLOCK 25
#define APP_CMD 55
#define READ_OCR 58
#define CRC_ON_OFF 59
/* Application specific commands supported by SD.
All these commands shall be preceded with APP_CMD (CMD55). */
#define SD_STATUS 13
#define SD_SEND_OP_COND 41
/* R1 response bit flag definition */
#define R1_NO_ERROR 0x00
#define R1_IN_IDLE_STATE 0x01
#define R1_ERASE_RESET 0x02
#define R1_ILLEGAL_CMD 0x04
#define R1_COM_CRC_ERROR 0x08
#define R1_ERASE_SEQ_ERROR 0x10
#define R1_ADDRESS_ERROR 0x20
#define R1_PARA_ERROR 0x40
#define R1_MASK 0x7F
/* The sector size is fixed to 512bytes in most applications. */
#define SECTOR_SIZE 512
/* Global variables */
uint8_t CardType; /* card type */
CARDCONFIG CardConfig; /* Card configuration */
/* Local variables */
static volatile WORD Timer1, Timer2; /* 100Hz decrement timer stopped at zero (disk_timerproc()) */
static volatile DSTATUS Stat = STA_NOINIT; /* Disk status */
#define SPI_CS_High() GPIO_SetBits(GPIOD,GPIO_Pin_1)
#define SPI_CS_Low() GPIO_ResetBits(GPIOD,GPIO_Pin_1)
#define SPI_CLOCKRATE_HIGH 8000000
#define SPI_CLOCKRATE_LOW 400000
#define SPI_ConfigClockRate (SPI_CLOCKRATE_HIGH)
extern uint8_t dgSpiRw(uint8_t dataW);
#define SPI_RecvByte() dgSpiRw(0xFF)
#define SPI_SendByte(x) dgSpiRw(x)
/** Select the card */
#define SD_Select() do {SPI_CS_Low();} while (0)
/** DeSelect the card */
#define SD_DeSelect() do { SPI_CS_High ();SPI_RecvByte();} while (0)
/*-----------------------------------------------------------------------*/
/* Initialize Disk Drive */
/*-----------------------------------------------------------------------*/
DSTATUS disk_initialize (
BYTE drv /* Physical drive number (0) */
)
{
if (drv) return STA_NOINIT; /* Supports only single drive */
if (Stat & STA_NODISK) return Stat; /* No card in the socket */
if (FS_SD_Init() && SD_ReadConfiguration())
Stat &= ~STA_NOINIT;
return Stat;
}
/*-----------------------------------------------------------------------*/
/* Miscellaneous Functions */
/*-----------------------------------------------------------------------*/
DRESULT disk_ioctl (
BYTE drv, /* Physical drive number (0) */
BYTE ctrl, /* Control code */
void *buff /* Buffer to send/receive control data */
)
{
DRESULT res;
BYTE n, *ptr = buff;
if (drv) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
res = RES_ERROR;
switch (ctrl) {
case CTRL_SYNC : /* Make sure that no pending write process */
SD_Select();
if (SD_WaitForReady() == SD_TRUE)
res = RES_OK;
break;
case GET_SECTOR_COUNT : /* Get number of sectors on the disk (DWORD) */
*(DWORD*)buff = CardConfig.sectorcnt;
res = RES_OK;
break;
case GET_SECTOR_SIZE : /* Get R/W sector size (WORD) */
*(WORD*)buff = CardConfig.sectorsize; //512;
res = RES_OK;
break;
case GET_BLOCK_SIZE : /* Get erase block size in unit of sector (DWORD) */
*(DWORD*)buff = CardConfig.blocksize;
res = RES_OK;
break;
case MMC_GET_TYPE : /* Get card type flags (1 byte) */
*ptr = CardType;
res = RES_OK;
break;
case MMC_GET_CSD : /* Receive CSD as a data block (16 bytes) */
for (n=0;n<16;n++)
*(ptr+n) = CardConfig.csd[n];
res = RES_OK;
break;
case MMC_GET_CID : /* Receive CID as a data block (16 bytes) */
for (n=0;n<16;n++)
*(ptr+n) = CardConfig.cid[n];
res = RES_OK;
break;
case MMC_GET_OCR : /* Receive OCR as an R3 resp (4 bytes) */
for (n=0;n<4;n++)
*(ptr+n) = CardConfig.ocr[n];
res = RES_OK;
break;
case MMC_GET_SDSTAT : /* Receive SD status as a data block (64 bytes) */
for (n=0;n<64;n++)
*(ptr+n) = CardConfig.status[n];
res = RES_OK;
break;
default:
res = RES_PARERR;
}
SD_DeSelect();
return res;
}
/*-----------------------------------------------------------------------*/
/* Read Sector(s) */
/*-----------------------------------------------------------------------*/
DRESULT disk_read (
BYTE drv, /* Physical drive number (0) */
BYTE *buff, /* Pointer to the data buffer to store read data */
DWORD sector, /* Start sector number (LBA) */
UINT count /* Sector count (1..255) */
)
{
if (drv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
if (SD_ReadSector (sector, buff, count) == SD_TRUE)
return RES_OK;
else
return RES_ERROR;
}
/*-----------------------------------------------------------------------*/
/* Get Disk Status */
/*-----------------------------------------------------------------------*/
DSTATUS disk_status (
BYTE drv /* Physical drive number (0) */
)
{
if (drv) return STA_NOINIT; /* Supports only single drive */
return Stat;
}
/*-----------------------------------------------------------------------*/
/* Write Sector(s) */
/*-----------------------------------------------------------------------*/
#if _READONLY == 0
DRESULT disk_write (
BYTE drv, /* Physical drive number (0) */
const BYTE *buff, /* Pointer to the data to be written */
DWORD sector, /* Start sector number (LBA) */
UINT count /* Sector count (1..255) */
)
{
if (drv || !count) return RES_PARERR;
if (Stat & STA_NOINIT) return RES_NOTRDY;
// if (Stat & STA_PROTECT) return RES_WRPRT;
if ( SD_WriteSector(sector, buff, count) == SD_TRUE)
return RES_OK;
else
return RES_ERROR;
}
#endif /* _READONLY == 0 */
/*-----------------------------------------------------------------------*/
/* Device timer function (Platform dependent) */
/*-----------------------------------------------------------------------*/
/* This function must be called from timer interrupt routine in period
/ of 10 ms to generate card control timing.
*/
void disk_timerproc (void)
{
static uint8_t Cnt;
WORD n;
Cnt++;
if(Cnt < 10)
return;
Cnt=0;
n = Timer1; /* 100Hz decrement timer stopped at 0 */
if (n) Timer1 = --n;
n = Timer2;
if (n) Timer2 = --n;
}
/**
* @brief Initializes the memory card.
*
* @param None
* @retval SD_TRUE: Init OK.
* SD_FALSE: Init failed.
*
* Note: Refer to the init flow at http://elm-chan.org/docs/mmc/sdinit.png
*/
SD_BOOL FS_SD_Init (void)
{
uint32_t i;
uint8_t r1, buf[4];
SPI_InitTypeDef SPI_InitStructure;
/* Set card type to unknown */
CardType = CARDTYPE_UNKNOWN;
/* Init SPI interface */
/*!< SD_SPI Periph clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI4, ENABLE);
RCC_AHB2PeriphResetCmd(RCC_APB2Periph_SPI4, ENABLE);
RCC_AHB2PeriphResetCmd(RCC_APB2Periph_SPI4, DISABLE);
/*!< SD_SPI Config */
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_256;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SD_SPI, &SPI_InitStructure);
SPI_Cmd(SD_SPI, ENABLE); /*!< SD_SPI enable */
/* Before reset, Send at least 74 clocks at low frequency
(between 100kHz and 400kHz) with CS high and DI (MISO) high. */
SD_DeSelect();
//SPI_ConfigClockRate (SPI_CLOCKRATE_LOW);
for (i = 0; i < 10; i++) SPI_SendByte (0xFF);
/* Send CMD0 with CS low to enter SPI mode and reset the card.
The card will enter SPI mode if CS is low during the reception of CMD0.
Since the CMD0 (and CMD8) must be sent as a native command, the CRC field
must have a valid value. */
if (SD_SendCommand (GO_IDLE_STATE, 0, NULL, 0) != R1_IN_IDLE_STATE) // CMD0
{
goto init_end;
}
/* Now the card enters IDLE state. */
/* Card type identification Start ... */
/* Check the card type, needs around 1000ms */
r1 = SD_SendCommand (SEND_IF_COND, 0x1AA, buf, 4); // CMD8
if (r1 & 0x80) goto init_end;
Timer1 = 100; // 1000ms
if (r1 == R1_IN_IDLE_STATE) { /* It's V2.0 or later SD card */
if (buf[2]!= 0x01 || buf[3]!=0xAA) goto init_end;
/* The card is SD V2 and can work at voltage range of 2.7 to 3.6V */
do {
r1 = SD_SendACommand (SD_SEND_OP_COND, 0x40000000, NULL, 0); // ACMD41
if (r1 == 0x00) break;
else if (r1 > 0x01) goto init_end;
} while (Timer1);
if (Timer1 && SD_SendCommand (READ_OCR, 0, buf, 4)==R1_NO_ERROR) // CMD58
CardType = (buf[0] & 0x40) ? CARDTYPE_SDV2_HC : CARDTYPE_SDV2_SC;
} else { /* It's Ver1.x SD card or MMC card */
/* Check if it is SD card */
if (SD_SendCommand (APP_CMD, 0, NULL, 0) & R1_ILLEGAL_CMD)
{
CardType = CARDTYPE_MMC;
while (Timer1 && SD_SendCommand (SEND_OP_COND, 0, NULL, 0));
}
else
{
CardType = CARDTYPE_SDV1;
while (Timer1 && SD_SendACommand (SD_SEND_OP_COND, 0, NULL, 0));
}
if (Timer1 == 0) CardType = CARDTYPE_UNKNOWN;
}
/* For SDHC or SDXC, block length is fixed to 512 bytes, for others,
the block length is set to 512 manually. */
if (CardType == CARDTYPE_MMC ||
CardType == CARDTYPE_SDV1 ||
CardType == CARDTYPE_SDV2_SC )
{
if (SD_SendCommand (SET_BLOCKLEN, SECTOR_SIZE, NULL, 0) != R1_NO_ERROR)
CardType = CARDTYPE_UNKNOWN;
}
init_end:
SD_DeSelect();
if (CardType == CARDTYPE_UNKNOWN)
{
return (SD_FALSE);
}
else /* Init OK. use high speed during data transaction stage. */
{
//SPI_ConfigClockRate (SPI_CLOCKRATE_HIGH);
return (SD_TRUE);
}
}
/**
* @brief Wait for the card is ready.
*
* @param None
* @retval SD_TRUE: Card is ready for read commands.
* SD_FALSE: Card is not ready
*/
SD_BOOL SD_WaitForReady (void)
{
Timer2 = 50; // 500ms
SPI_RecvByte(); /* Read a byte (Force enable DO output) */
do {
if (SPI_RecvByte () == 0xFF) return SD_TRUE;
} while (Timer2);
return SD_FALSE;
}
/**
* @brief Send a command and receive a response with specified format.
*
* @param cmd: Specifies the command index.
* @param arg: Specifies the argument.
* @param buf: Pointer to byte array to store the response content.
* @param len: Specifies the byte number to be received after R1 response.
* @retval Value below 0x80 is the normal R1 response (0x0 means no error)
* Value above 0x80 is the additional returned status code.
* 0x81: Card is not ready
* 0x82: command response time out error
*/
uint8_t SD_SendCommand (uint8_t cmd, uint32_t arg, uint8_t *buf, uint32_t len)
{
uint32_t r1,i;
uint8_t crc_stop;
/* The CS signal must be kept low during a transaction */
SD_Select();
/* Wait until the card is ready to read (DI signal is High) */
if (SD_WaitForReady() == SD_FALSE) return 0x81;
/* Prepare CRC7 + stop bit. For cmd GO_IDLE_STATE and SEND_IF_COND,
the CRC7 should be valid, otherwise, the CRC7 will be ignored. */
if (cmd == GO_IDLE_STATE) crc_stop = 0x95; /* valid CRC7 + stop bit */
else if (cmd == SEND_IF_COND) crc_stop = 0x87; /* valid CRC7 + stop bit */
else crc_stop = 0x01; /* dummy CRC7 + Stop bit */
/* Send 6-byte command with CRC. */
SPI_SendByte (cmd | 0x40);
SPI_SendByte (arg >> 24);
SPI_SendByte (arg >> 16);
SPI_SendByte (arg >> 8);
SPI_SendByte (arg);
SPI_SendByte (crc_stop); /* Valid or dummy CRC plus stop bit */
/* The command response time (Ncr) is 0 to 8 bytes for SDC,
1 to 8 bytes for MMC. */
for (i = 8; i; i--)
{
r1 = SPI_RecvByte ();
if (r1 != 0xFF) break; /* received valid response */
}
if (i == 0) return (0x82); /* command response time out error */
/* Read remaining bytes after R1 response */
if (buf && len)
{
do {
*buf++ = SPI_RecvByte ();
} while (--len);
}
return (r1);
}
/**
* @brief Send an application specific command for SD card
* and receive a response with specified format.
*
* @param cmd: Specifies the command index.
* @param arg: Specifies the argument.
* @param buf: Pointer to byte array to store the response content.
* @param len: Specifies the byte number to be received after R1 response.
* @retval Value below 0x80 is the normal R1 response(0x0 means no error)
* Value above 0x80 is the additional returned status code.
* 0x81: Card is not ready
* 0x82: command response time out error
*
* Note: All the application specific commands should be precdeded with APP_CMD
*/
uint8_t SD_SendACommand (uint8_t cmd, uint32_t arg, uint8_t *buf, uint32_t len)
{
uint8_t r1;
/* Send APP_CMD (CMD55) first */
r1 = SD_SendCommand(APP_CMD, 0, NULL, 0);
if (r1 > 1) return r1;
return (SD_SendCommand (cmd, arg, buf, len));
}
/**
* @brief Read single or multiple sector(s) from memory card.
*
* @param sect: Specifies the starting sector index to read
* @param buf: Pointer to byte array to store the data
* @param cnt: Specifies the count of sectors to read
* @retval SD_TRUE or SD_FALSE.
*/
SD_BOOL SD_ReadSector (uint32_t sect, uint8_t *buf, uint32_t cnt)
{
SD_BOOL flag;
/* Convert sector-based address to byte-based address for non SDHC */
if (CardType != CARDTYPE_SDV2_HC) sect <<= 9;
flag = SD_FALSE;
if (cnt > 1) /* Read multiple block */
{
if (SD_SendCommand(READ_MULTIPLE_BLOCK, sect, NULL, 0) == R1_NO_ERROR)
{
do {
if (SD_RecvDataBlock(buf, SECTOR_SIZE) == SD_FALSE) break;
buf += SECTOR_SIZE;
} while (--cnt);
/* Stop transmission */
SD_SendCommand(STOP_TRANSMISSION, 0, NULL, 0);
/* Wait for the card is ready */
if (SD_WaitForReady() && cnt==0) flag = SD_TRUE;
}
}
else /* Read single block */
{
if ((SD_SendCommand(READ_SINGLE_BLOCK, sect, NULL, 0)==R1_NO_ERROR) &&
SD_RecvDataBlock(buf, SECTOR_SIZE)==SD_TRUE)
flag = SD_TRUE;
}
/* De-select the card */
SD_DeSelect();
return (flag);
}
/**
* @brief Write single or multiple sectors to SD/MMC.
*
* @param sect: Specifies the starting sector index to write
* @param buf: Pointer to the data array to be written
* @param cnt: Specifies the number sectors to be written
* @retval SD_TRUE or SD_FALSE
*/
SD_BOOL SD_WriteSector (uint32_t sect, const uint8_t *buf, uint32_t cnt)
{
SD_BOOL flag;
/* Convert sector-based address to byte-based address for non SDHC */
if (CardType != CARDTYPE_SDV2_HC) sect <<= 9;
flag = SD_FALSE;
if (cnt > 1) /* write multiple block */
{
if (SD_SendCommand (WRITE_MULTIPLE_BLOCK, sect, NULL, 0) == R1_NO_ERROR)
{
do {
if (SD_SendDataBlock (buf, 0xFC, SECTOR_SIZE) == SD_FALSE) break;
buf += SECTOR_SIZE;
} while (--cnt);
/* Send Stop Transmission Token. */
SPI_SendByte (0xFD);
/* Wait for complete */
if (SD_WaitForReady() && cnt==0) flag = SD_TRUE;
}
}
else /* write single block */
{
if ( (SD_SendCommand (WRITE_SINGLE_BLOCK, sect, NULL, 0) == R1_NO_ERROR) &&
(SD_SendDataBlock (buf, 0xFE, SECTOR_SIZE) == SD_TRUE))
flag = SD_TRUE;
}
/* De-select the card */
SD_DeSelect();
return (flag);
}
/**
* @brief Read card configuration and fill structure CardConfig.
*
* @param None
* @retval SD_TRUE or SD_FALSE.
*/
SD_BOOL SD_ReadConfiguration ()
{
uint8_t buf[16];
uint32_t i, c_size, c_size_mult, read_bl_len;
SD_BOOL retv;
retv = SD_FALSE;
/* Read OCR */
if (SD_SendCommand(READ_OCR, 0, CardConfig.ocr, 4) != R1_NO_ERROR) goto end;
/* Read CID */
if ((SD_SendCommand(SEND_CID, 0, NULL, 0) != R1_NO_ERROR) ||
SD_RecvDataBlock (CardConfig.cid, 16)==SD_FALSE) goto end;
/* Read CSD */
if ((SD_SendCommand(SEND_CSD, 0, NULL, 0) != R1_NO_ERROR) ||
SD_RecvDataBlock (CardConfig.csd, 16)==SD_FALSE) goto end;
/* sector size */
CardConfig.sectorsize = 512;
/* sector count */
if (((CardConfig.csd[0]>>6) & 0x3) == 0x1) /* CSD V2.0 (for High/eXtended Capacity) */
{
/* Read C_SIZE */
c_size = (((uint32_t)CardConfig.csd[7]<<16) + ((uint32_t)CardConfig.csd[8]<<8) + CardConfig.csd[9]) & 0x3FFFFF;
/* Calculate sector count */
CardConfig.sectorcnt = (c_size + 1) * 1024;
} else /* CSD V1.0 (for Standard Capacity) */
{
/* C_SIZE */
c_size = (((uint32_t)(CardConfig.csd[6]&0x3)<<10) + ((uint32_t)CardConfig.csd[7]<<2) + (CardConfig.csd[8]>>6)) & 0xFFF;
/* C_SIZE_MUTE */
c_size_mult = ((CardConfig.csd[9]&0x3)<<1) + ((CardConfig.csd[10]&0x80)>>7);
/* READ_BL_LEN */
read_bl_len = CardConfig.csd[5] & 0xF;
/* sector count = BLOCKNR*BLOCK_LEN/512, we manually set SECTOR_SIZE to 512*/
//CardConfig.sectorcnt = (c_size+1)*(1<<read_bl_len) * (1<<(c_size_mult+2)) / 512;
CardConfig.sectorcnt = (c_size+1) << (read_bl_len + c_size_mult - 7);
}
/* Get erase block size in unit of sector */
switch (CardType)
{
case CARDTYPE_SDV2_SC:
case CARDTYPE_SDV2_HC:
if ((SD_SendACommand (SD_STATUS, 0, buf, 1) != R1_NO_ERROR) ||
SD_RecvDataBlock(buf, 16) == SD_FALSE) goto end; /* Read partial block */
for (i=64-16;i;i--) SPI_RecvByte(); /* Purge trailing data */
CardConfig.blocksize = 16UL << (buf[10] >> 4); /* Calculate block size based on AU size */
break;
case CARDTYPE_MMC:
//CardConfig.blocksize = ((uint16_t)((CardConfig.csd[10] & 124) >> 2) + 1) * (((CardConfig.csd[11] & 3) << 3) + ((CardConfig.csd[11] & 224) >> 5) + 1);
CardConfig.blocksize = ((uint16_t)((CardConfig.csd[10] & 124) >> 2) + 1) * (((CardConfig.csd[10] & 3) << 3) + ((CardConfig.csd[11] & 224) >> 5) + 1);
break;
case CARDTYPE_SDV1:
CardConfig.blocksize = (((CardConfig.csd[10] & 63) << 1) + ((uint16_t)(CardConfig.csd[11] & 128) >> 7) + 1) << ((CardConfig.csd[13] >> 6) - 1);
break;
default:
goto end;
}
retv = SD_TRUE;
end:
SD_DeSelect ();
return retv;
}
/**
* @brief Receive a data block with specified length from SD/MMC.
*
* @param buf: Pointer to the data array to store the received data
* @param len: Specifies the length (in byte) to be received.
* The value should be a multiple of 4.
* @retval SD_TRUE or SD_FALSE
*/
SD_BOOL SD_RecvDataBlock (uint8_t *buf, uint32_t len)
{
uint8_t datatoken;
uint32_t i;
/* Read data token (0xFE) */
Timer1 = 10; /* Data Read Timerout: 100ms */
do {
datatoken = SPI_RecvByte ();
if (datatoken == 0xFE) break;
} while (Timer1);
if(datatoken != 0xFE) return (SD_FALSE); /* data read timeout */
/* Read data block */
#ifdef USE_FIFO
SPI_RecvBlock_FIFO (buf, len);
#else
for (i = 0; i < len; i++) {
buf[i] = SPI_RecvByte ();
}
#endif
/* 2 bytes CRC will be discarded. */
SPI_RecvByte ();
SPI_RecvByte ();
return (SD_TRUE);
}
/**
* @brief Send a data block with specified length to SD/MMC.
*
* @param buf: Pointer to the data array to store the received data
* @param tkn: Specifies the token to send before the data block
* @param len: Specifies the length (in byte) to send.
* The value should be 512 for memory card.
* @retval SD_TRUE or SD_FALSE
*/
SD_BOOL SD_SendDataBlock (const uint8_t *buf, uint8_t tkn, uint32_t len)
{
uint8_t recv;
uint32_t i;
/* Send Start Block Token */
SPI_SendByte (tkn);
/* Send data block */
#ifdef USE_FIFO
SPI_SendBlock_FIFO (buf, len);
#else
for (i = 0; i < len; i++)
{
SPI_SendByte (buf[i]);
}
#endif
/* Send 2 bytes dummy CRC */
SPI_SendByte (0xFF);
SPI_SendByte (0xFF);
/* Read data response to check if the data block has been accepted. */
if (( (SPI_RecvByte ()) & 0x0F) != 0x05)
return (SD_FALSE); /* write error */
/* Wait for wirte complete. */
Timer1 = 20; // 200ms
do {
recv = SPI_RecvByte();
if (recv == 0xFF) break;
} while (Timer1);
if (recv == 0xFF) return SD_TRUE; /* write complete */
else return (SD_FALSE); /* write time out */
}
/* --------------------------------- End Of File ------------------------------ */

复制代码

演示程序：
IDE ： IAR ARM8.11
操作系统： freeRTOS
文件系统： FATFS0.12

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FATFS文件系统-SD卡

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