fread, descripcion y ejemplo

Dependencies:   mbed

Files at this revision

API Documentation at this revision

Comitter:
sherckuith
Date:
Tue Apr 03 21:01:22 2012 +0000
Commit message:
descripcion y ejemplo

Changed in this revision

FATFileSystem.lib Show annotated file Show diff for this revision Revisions of this file
SDFileSystem_Sherckuith/SDFileSystem.cpp Show annotated file Show diff for this revision Revisions of this file
SDFileSystem_Sherckuith/SDFileSystem.h Show annotated file Show diff for this revision Revisions of this file
main.cpp Show annotated file Show diff for this revision Revisions of this file
mbed.bld Show annotated file Show diff for this revision Revisions of this file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/FATFileSystem.lib	Tue Apr 03 21:01:22 2012 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_unsupported/code/fatfilesystem/
\ No newline at end of file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SDFileSystem_Sherckuith/SDFileSystem.cpp	Tue Apr 03 21:01:22 2012 +0000
@@ -0,0 +1,378 @@
+#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;
+}
\ No newline at end of file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SDFileSystem_Sherckuith/SDFileSystem.h	Tue Apr 03 21:01:22 2012 +0000
@@ -0,0 +1,40 @@
+#ifndef MBED_SDFILESYSTEM_H
+#define MBED_SDFILESYSTEM_H
+
+#include "mbed.h"
+#include "FATFileSystem.h"
+
+extern "C" void mbed_reset();
+
+class SDFileSystem : public FATFileSystem {
+public:
+
+    SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name);
+    virtual int disk_initialize();
+    void init_bios();
+    virtual int disk_write(const char *buffer, int block_number);
+    virtual int disk_read(char *buffer, int block_number);    
+    virtual int disk_status();
+    virtual int disk_sync();
+    virtual int disk_sectors();
+
+protected:
+
+    int _cmd(int cmd, int arg);
+    int _cmdx(int cmd, int arg);
+    int _cmd8();
+    int _cmd58();
+    int initialise_card();
+    int initialise_card_v1();
+    int initialise_card_v2();
+    
+    int _read(char *buffer, int length);
+    int _write(const char *buffer, int length);
+    int _sd_sectors();
+    int _sectors;
+    
+    SPI _spi;
+    DigitalOut _cs;     
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Tue Apr 03 21:01:22 2012 +0000
@@ -0,0 +1,74 @@
+#include "mbed.h"
+#include "SDFileSystem.h"
+
+Serial          pc(USBTX, USBRX);
+LocalFileSystem chip("uc");
+SDFileSystem    sd(p5, p6, p7, p8,"sd");
+
+int main () {
+    pc.baud(115200);
+    FILE * pFile;
+    long lSize;
+    char * buffer;
+    size_t result;
+
+    pFile = fopen ( "/sd/Justin.mp3","r");
+    if (pFile==NULL) {
+        fputs ("File error",stderr);
+        exit (1);
+    }
+    // obtain file size:
+    fseek (pFile , 0 , SEEK_END);
+    lSize = ftell (pFile);
+    rewind (pFile);
+    pc.printf("Tamanio: %d\n",lSize);
+    wait(3);
+    // allocate memory to contain the whole file:
+    buffer = (char*) malloc (sizeof(char)*lSize);
+    if (buffer == NULL) {
+        fputs ("Memory error",stderr);
+        exit (2);
+    }
+    // copy the file into the buffer:
+    result = fread (buffer,1,lSize,pFile);
+    if (result != lSize) {
+        fputs ("Reading error",stderr);
+        exit (3);
+    }
+    pc.printf("%s",buffer);
+    /* the whole file is now loaded in the memory buffer. */
+    fclose (pFile);
+    free (buffer);
+    return 0;
+}
+
+//This code loads myfile.bin into a dynamically allocated memory buffer,
+//which can be used to manipulate the content of a file as an array.
+
+
+/*
+function: fread
+Library:  <cstdio>
+
+size_t fread ( void * ptr, size_t size, size_t count, FILE * stream );
+
+Read block of data from stream
+Reads an array of count elements, each one with a size of size bytes, from the stream and stores them in the block of memory specified by ptr.
+The postion indicator of the stream is advanced by the total amount of bytes read.
+The total amount of bytes read if successful is (size * count).
+
+Parameters
+
+ptr         Pointer to a block of memory with a minimum size of (size*count) bytes.
+size        Size in bytes of each element to be read.
+count       Number of elements, each one with a size of size bytes.
+stream      Pointer to a FILE object that specifies an input stream.
+
+
+Return Value
+The total number of elements successfully read is returned as a size_t object, which is an integral data type.
+If this number differs from the count parameter, either an error occured or the End Of File was reached.
+You can use either ferror or feof to check whether an error happened or the End-of-File was reached.
+*/
+
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Tue Apr 03 21:01:22 2012 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/737756e0b479