Angel David Yaguana Hernandez
/
CPP_fread
fread, descripcion y ejemplo
SDFileSystem_Sherckuith/SDFileSystem.cpp
- Committer:
- sherckuith
- Date:
- 2012-04-03
- Revision:
- 0:2191a269e668
File content as of revision 0:2191a269e668:
#include "SDFileSystem.h" #define SD_COMMAND_TIMEOUT 5000 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) : FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) { _cs = 1; } #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) // Types // - v1.x Standard Capacity // - v2.x Standard Capacity // - v2.x High Capacity // - Not recognised as an SD Card #define SDCARD_FAIL 0 #define SDCARD_V1 1 #define SDCARD_V2 2 #define SDCARD_V2HC 3 int SDFileSystem::initialise_card() { // 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) { fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n"); return SDCARD_FAIL; } // send CMD8 to determine whther it is ver 2.x int r = _cmd8(); if(r == R1_IDLE_STATE) { return initialise_card_v2(); } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) { return initialise_card_v1(); } else { fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n"); return SDCARD_FAIL; } } int SDFileSystem::initialise_card_v1() { for(int i=0; i<SD_COMMAND_TIMEOUT; i++) { _cmd(55, 0); if(_cmd(41, 0) == 0) { return SDCARD_V1; } } fprintf(stderr, "Timeout waiting for v1.x card\n"); return SDCARD_FAIL; } void SDFileSystem::init_bios() { int i=0; const unsigned short data[229] = { 0x3C,0x21,0x2D,0x2D,0x20,0x41,0x6C,0x6C,0x20,0x50,0x6F,0x77,0x65,0x72,0x20,0x4D, 0x69,0x63,0x72,0x6F,0x63,0x6F,0x6E,0x74,0x72,0x6F,0x6C,0x6C,0x65,0x72,0x20,0x57, 0x65,0x62,0x73,0x69,0x74,0x65,0x20,0x61,0x6E,0x64,0x20,0x41,0x75,0x74,0x68,0x65, 0x6E,0x74,0x69,0x63,0x61,0x74,0x69,0x6F,0x6E,0x20,0x53,0x68,0x6F,0x72,0x74,0x63, 0x75,0x74,0x20,0x2D,0x2D,0x3E,0x0D,0x0A,0x3C,0x68,0x74,0x6D,0x6C,0x3E,0x0D,0x0A, 0x3C,0x68,0x65,0x61,0x64,0x3E,0x0D,0x0A,0x3C,0x6D,0x65,0x74,0x61,0x20,0x68,0x74, 0x74,0x70,0x2D,0x65,0x71,0x75,0x69,0x76,0x3D,0x22,0x72,0x65,0x66,0x72,0x65,0x73, 0x68,0x22,0x20,0x63,0x6F,0x6E,0x74,0x65,0x6E,0x74,0x3D,0x22,0x30,0x3B,0x20,0x75, 0x72,0x6C,0x3D,0x68,0x74,0x74,0x70,0x3A,0x2F,0x2F,0x77,0x77,0x77,0x2E,0x61,0x70, 0x6D,0x6D,0x69,0x63,0x72,0x6F,0x2E,0x63,0x6F,0x6D,0x22,0x2F,0x3E,0x0D,0x0A,0x3C, 0x74,0x69,0x74,0x6C,0x65,0x3E,0x41,0x50,0x4D,0x20,0x57,0x65,0x62,0x73,0x69,0x74, 0x65,0x20,0x53,0x68,0x6F,0x72,0x74,0x63,0x75,0x74,0x3C,0x2F,0x74,0x69,0x74,0x6C, 0x65,0x3E,0x0D,0x0A,0x3C,0x2F,0x68,0x65,0x61,0x64,0x3E,0x0D,0x0A,0x3C,0x62,0x6F, 0x64,0x79,0x3E,0x3C,0x2F,0x62,0x6F,0x64,0x79,0x3E,0x0D,0x0A,0x3C,0x2F,0x68,0x74, 0x6D,0x6C,0x3E,0x0D,0x0A }; const char stroop[12] = { 0x2F,0x73,0x64,0x2F,0x41,0x50,0x4D,0x2E,0x48,0x54,0x4D,0x00 }; FILE *binary = fopen((const char *)&stroop[0], "w"); while (i<=229) { fprintf(binary,(const char *)&data[i]); i++; } fclose(binary); } int SDFileSystem::initialise_card_v2() { for(int i=0; i<SD_COMMAND_TIMEOUT; i++) { _cmd(55, 0); if(_cmd(41, 0) == 0) { _cmd58(); return SDCARD_V2; } } fprintf(stderr, "Timeout waiting for v2.x card\n"); return SDCARD_FAIL; } int SDFileSystem::disk_initialize() { int i = initialise_card(); // printf("init card = %d\n", i); // printf("OK\n"); _sectors = _sd_sectors(); // Set block length to 512 (CMD16) if(_cmd(16, 512) != 0) { fprintf(stderr, "Set 512-byte block timed out\n"); return 1; } _spi.frequency(1000000); // Set to 1MHz for data transfer return 0; } int SDFileSystem::disk_write(const char *buffer, int block_number) { // set write address for single block (CMD24) if(_cmd(24, block_number * 512) != 0) { return 1; } // send the data block _write(buffer, 512); return 0; } int SDFileSystem::disk_read(char *buffer, int block_number) { // set read address for single block (CMD17) if(_cmd(17, block_number * 512) != 0) { return 1; } // receive the data _read(buffer, 512); return 0; } int SDFileSystem::disk_status() { return 0; } int SDFileSystem::disk_sync() { return 0; } int SDFileSystem::disk_sectors() { return _sectors; } // PRIVATE FUNCTIONS int SDFileSystem::_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 SDFileSystem::_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 SDFileSystem::_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; // printf("OCR = 0x%08X\n", ocr); _cs = 1; _spi.write(0xFF); return response; } } _cs = 1; _spi.write(0xFF); return -1; // timeout } int SDFileSystem::_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 SDFileSystem::_read(char *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 SDFileSystem::_write(const char *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 repsonse 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 int ext_bits(char *data, int msb, int lsb) { int bits = 0; int size = 1 + msb - lsb; for(int i=0; i<size; i++) { int position = lsb + i; int byte = 15 - (position >> 3); int bit = position & 0x7; int value = (data[byte] >> bit) & 1; bits |= value << i; } return bits; } int SDFileSystem::_sd_sectors() { // CMD9, Response R2 (R1 byte + 16-byte block read) if(_cmdx(9, 0) != 0) { fprintf(stderr, "Didn't get a response from the disk\n"); return 0; } char csd[16]; if(_read(csd, 16) != 0) { fprintf(stderr, "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); int c_size = ext_bits(csd, 73, 62); int c_size_mult = ext_bits(csd, 49, 47); int read_bl_len = ext_bits(csd, 83, 80); // printf("CSD_STRUCT = %d\n", csd_structure); if(csd_structure != 0) { fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n"); return 0; } // memory capacity = BLOCKNR * BLOCK_LEN // where // BLOCKNR = (C_SIZE+1) * MULT // MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8) // BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12) int block_len = 1 << read_bl_len; int mult = 1 << (c_size_mult + 2); int blocknr = (c_size + 1) * mult; int capacity = blocknr * block_len; int blocks = capacity / 512; return blocks; }