updated chan_fatfs
Fork of chan_fatfs by
diskio.cpp
- Committer:
- tylerjw
- Date:
- 2012-12-28
- Revision:
- 8:1f9748c6b865
- Parent:
- 4:f88948891a05
File content as of revision 8:1f9748c6b865:
/*-----------------------------------------------------------------------*/ /* Low level disk I/O module skeleton for FatFs (C)ChaN, 2007 */ /*-----------------------------------------------------------------------*/ /* This is a stub disk I/O module that acts as front end of the existing */ /* disk I/O modules and attach it to FatFs module with common interface. */ /*-----------------------------------------------------------------------*/ #include "diskio.h" #include "mbed.h" #include "mbed_debug.h" //****************************************************************************************************************** // MBED SPI/CS Select functions.... Modify for your layout. //************************************************************************************** SPI _spi(p5, p6, p7); // mosi, miso, sclk DigitalOut _cs(p8); //****************************************************************************************************************** // Low Level Sector Access Function Prototypes('C' Castrated versions of Simon Ford's C++ MBED SDFileSystem class //****************************************************************************************************************** int _cmd(int cmd, int arg); int _read(BYTE *buffer, int length); int _write(BYTE *buffer, int length); uint32_t ext_bits(BYTE *data, int msb, int lsb); int _sd_sectors(); int _sectors; int _cmd(int cmd, int arg); int _cmdx(int cmd, int arg); int _cmd8(); int _cmd58(); int cdv; #define SD_COMMAND_TIMEOUT 5000 #define R1_IDLE_STATE (1 << 0) #define R1_ERASE_RESET (1 << 1) #define R1_ILLEGAL_COMMAND (1 << 2) #define R1_COM_CRC_ERROR (1 << 3) #define R1_ERASE_SEQUENCE_ERROR (1 << 4) #define R1_ADDRESS_ERROR (1 << 5) #define R1_PARAMETER_ERROR (1 << 6) //****************************************************************************************************************** // Sector Access functions for CHAN FatFs //****************************************************************************************************************** DRESULT disk_ioctl ( BYTE drv, /* Physical drive nmuber (0..) */ BYTE ctrl, /* Control code */ void *buff /* Buffer to send/receive control data */ ) { DRESULT res; switch(ctrl) { case CTRL_SYNC: res = RES_OK; break; case GET_SECTOR_SIZE: res = RES_OK; *(WORD *)buff = 512; break; case GET_SECTOR_COUNT: res = RES_OK; *(DWORD *)buff = (WORD)_sd_sectors(); break; case GET_BLOCK_SIZE: res = RES_OK; *(DWORD *)buff = 1; break; default: res = RES_OK; break; } return res; } DSTATUS card_initialize(BYTE Drive) { // Set to 100kHz for initialisation, and clock card with cs = 1 _spi.frequency(100000); _cs = 1; for (int i = 0; i < 16; i++) { _spi.write(0xFF); } // send CMD0, should return with all zeros except IDLE STATE set (bit 0) if (_cmd(0, 0) != R1_IDLE_STATE) { debug("No disk, or could not put SD card in to SPI idle state\n"); return STA_NOINIT; } // send CMD8 to determine whther it is ver 2.x int r = _cmd8(); if (r == R1_IDLE_STATE) { for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) { wait_ms(50); _cmd58(); _cmd(55, 0); if (_cmd(41, 0x40000000) == 0) { _cmd58(); //debug_if(SD_DBG, "\n\rInit: SDCARD_V2\n\r"); cdv = 1; return 0; } } debug("Timeout waiting for v2.x card\n"); return STA_NOINIT; } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) { for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) { _cmd(55, 0); if (_cmd(41, 0) == 0) { cdv = 512; //debug_if(SD_DBG, "\n\rInit: SEDCARD_V1\n\r"); return 0; } } debug("Timeout waiting for v1.x card\n"); return STA_NOINIT; } else { debug("Not in idle state after sending CMD8 (not an SD card?)\n"); return STA_NOINIT; } } DSTATUS disk_initialize(BYTE Drive) { DSTATUS ret = card_initialize(Drive); _sectors = _sd_sectors(); // Set block length to 512 (CMD16) if (_cmd(16, 512) != 0) { debug("Set 512-byte block timed out\n"); return STA_NOINIT; } _spi.frequency(10000000); // Set to 10MHz for data transfer return ret; } DRESULT disk_write(BYTE Drive,const BYTE * Buffer, DWORD SectorNumber, BYTE SectorCount) { BYTE i; BYTE * MyBufOut = (BYTE *)Buffer; for(i=0; i<SectorCount; i++) { // set write address for single block (CMD24) if(_cmd(24, (SectorNumber + i) * 512 ) != 0) { return RES_ERROR; } // send the data block _write(MyBufOut, 512); MyBufOut+=512; } return RES_OK; } DRESULT disk_read(BYTE Drive, BYTE * Buffer,DWORD SectorNumber, BYTE SectorCount) { BYTE i; for(i=0; i<SectorCount; i++) { // set read address for single block (CMD17) if(_cmd(17, (SectorNumber+i) * 512) != 0) { return RES_ERROR; } // receive the data _read(Buffer, 512); Buffer+=512; } return RES_OK; } DWORD get_fattime(void) { time_t CurrentTimeStamp; tm *CurrentLocalTime; DWORD FATFSTimeCode; CurrentTimeStamp = time(NULL); CurrentLocalTime = localtime(&CurrentTimeStamp); //Map the tm struct time into the FatFs time code FATFSTimeCode = ((CurrentLocalTime->tm_year-80)<<25) | ((CurrentLocalTime->tm_mon+1)<<21) | ((CurrentLocalTime->tm_mday)<<16) | ((CurrentLocalTime->tm_hour)<<11) | ((CurrentLocalTime->tm_min)<<5) | ((CurrentLocalTime->tm_sec)); return FATFSTimeCode; } DSTATUS disk_status(BYTE Drive) { return 0; } //************************************************************************************** // Low Level Sector Access Functions (Castrated versions of Simon Fords C++ MBED class //************************************************************************************** int _cmd(int cmd, int arg) { _cs = 0; // send a command _spi.write(0x40 | cmd); _spi.write(arg >> 24); _spi.write(arg >> 16); _spi.write(arg >> 8); _spi.write(arg >> 0); _spi.write(0x95); // wait for the repsonse (response[7] == 0) for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) { int response = _spi.write(0xFF); if (!(response & 0x80)) { _cs = 1; _spi.write(0xFF); return response; } } _cs = 1; _spi.write(0xFF); return -1; // timeout } int _cmdx(int cmd, int arg) { _cs = 0; // send a command _spi.write(0x40 | cmd); _spi.write(arg >> 24); _spi.write(arg >> 16); _spi.write(arg >> 8); _spi.write(arg >> 0); _spi.write(0x95); // wait for the repsonse (response[7] == 0) for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) { int response = _spi.write(0xFF); if (!(response & 0x80)) { return response; } } _cs = 1; _spi.write(0xFF); return -1; // timeout } int _cmd58() { _cs = 0; int arg = 0; // send a command _spi.write(0x40 | 58); _spi.write(arg >> 24); _spi.write(arg >> 16); _spi.write(arg >> 8); _spi.write(arg >> 0); _spi.write(0x95); // wait for the repsonse (response[7] == 0) for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) { int response = _spi.write(0xFF); if (!(response & 0x80)) { int ocr = _spi.write(0xFF) << 24; ocr |= _spi.write(0xFF) << 16; ocr |= _spi.write(0xFF) << 8; ocr |= _spi.write(0xFF) << 0; _cs = 1; _spi.write(0xFF); return response; } } _cs = 1; _spi.write(0xFF); return -1; // timeout } int _cmd8() { _cs = 0; // send a command _spi.write(0x40 | 8); // CMD8 _spi.write(0x00); // reserved _spi.write(0x00); // reserved _spi.write(0x01); // 3.3v _spi.write(0xAA); // check pattern _spi.write(0x87); // crc // wait for the repsonse (response[7] == 0) for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) { char response[5]; response[0] = _spi.write(0xFF); if (!(response[0] & 0x80)) { for (int j = 1; j < 5; j++) { response[i] = _spi.write(0xFF); } _cs = 1; _spi.write(0xFF); return response[0]; } } _cs = 1; _spi.write(0xFF); return -1; // timeout } int _read(BYTE *buffer, int length) { _cs = 0; // read until start byte (0xFF) while (_spi.write(0xFF) != 0xFE); // read data for (int i = 0; i < length; i++) { buffer[i] = _spi.write(0xFF); } _spi.write(0xFF); // checksum _spi.write(0xFF); _cs = 1; _spi.write(0xFF); return 0; } int _write(BYTE *buffer, int length) { _cs = 0; // indicate start of block _spi.write(0xFE); // write the data for (int i = 0; i < length; i++) { _spi.write(buffer[i]); } // write the checksum _spi.write(0xFF); _spi.write(0xFF); // check the response token if ((_spi.write(0xFF) & 0x1F) != 0x05) { _cs = 1; _spi.write(0xFF); return 1; } // wait for write to finish while (_spi.write(0xFF) == 0); _cs = 1; _spi.write(0xFF); return 0; } static uint32_t ext_bits(unsigned char *data, int msb, int lsb) { uint32_t bits = 0; uint32_t size = 1 + msb - lsb; for (int i = 0; i < size; i++) { uint32_t position = lsb + i; uint32_t byte = 15 - (position >> 3); uint32_t bit = position & 0x7; uint32_t value = (data[byte] >> bit) & 1; bits |= value << i; } return bits; } int _sd_sectors() { uint32_t c_size, c_size_mult, read_bl_len; uint32_t block_len, mult, blocknr, capacity; uint32_t hc_c_size; uint64_t blocks; // CMD9, Response R2 (R1 byte + 16-byte block read) if (_cmdx(9, 0) != 0) { debug("Didn't get a response from the disk\n"); return 0; } uint8_t csd[16]; if (_read(csd, 16) != 0) { debug("Couldn't read csd response from disk\n"); return 0; } // csd_structure : csd[127:126] // c_size : csd[73:62] // c_size_mult : csd[49:47] // read_bl_len : csd[83:80] - the *maximum* read block length int csd_structure = ext_bits(csd, 127, 126); switch (csd_structure) { case 0: cdv = 512; c_size = ext_bits(csd, 73, 62); c_size_mult = ext_bits(csd, 49, 47); read_bl_len = ext_bits(csd, 83, 80); block_len = 1 << read_bl_len; mult = 1 << (c_size_mult + 2); blocknr = (c_size + 1) * mult; capacity = blocknr * block_len; blocks = capacity / 512; //debug_if(SD_DBG, "\n\rSDCard\n\rc_size: %d \n\rcapacity: %ld \n\rsectors: %lld\n\r", c_size, capacity, blocks); break; case 1: cdv = 1; hc_c_size = ext_bits(csd, 63, 48); blocks = (hc_c_size+1)*1024; //debug_if(SD_DBG, "\n\rSDHC Card \n\rhc_c_size: %d\n\rcapacity: %lld \n\rsectors: %lld\n\r", hc_c_size, blocks*512, blocks); break; default: debug("CSD struct unsupported\r\n"); return 0; }; return blocks; }