USBMSD example using an SD card

Dependents:   USBMSD_SD_HelloWorld_FRDM-KL25Z USBMSD_SD_HelloWorld_Mbed USBMSD_SD_HelloWorld_FRDM-KL25Z V09_01h ... more

Files at this revision

API Documentation at this revision

Comitter:
samux
Date:
Mon Jan 21 10:40:05 2013 +0000
Parent:
1:923991b026e7
Commit message:
use latest SDFilesystem library

Changed in this revision

USBMSD_SD.cpp Show annotated file Show diff for this revision Revisions of this file
USBMSD_SD.h Show annotated file Show diff for this revision Revisions of this file
diff -r 923991b026e7 -r 055119ccf5a7 USBMSD_SD.cpp
--- a/USBMSD_SD.cpp	Sun Dec 11 15:52:35 2011 +0000
+++ b/USBMSD_SD.cpp	Mon Jan 21 10:40:05 2013 +0000
@@ -1,5 +1,5 @@
-/* mbed USBMSD_SD Library, for providing file access to SD cards
- * Copyright (c) 2008-2010, sford
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2012 ARM Limited
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -16,28 +16,27 @@
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
  */
-
 /* Introduction
  * ------------
  * SD and MMC cards support a number of interfaces, but common to them all
  * is one based on SPI. This is the one I'm implmenting because it means
- * it is much more portable even though not so performant, and we already 
+ * it is much more portable even though not so performant, and we already
  * have the mbed SPI Interface!
  *
- * The main reference I'm using is Chapter 7, "SPI Mode" of: 
+ * The main reference I'm using is Chapter 7, "SPI Mode" of:
  *  http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
  *
  * SPI Startup
  * -----------
  * The SD card powers up in SD mode. The SPI interface mode is selected by
- * asserting CS low and sending the reset command (CMD0). The card will 
+ * asserting CS low and sending the reset command (CMD0). The card will
  * respond with a (R1) response.
  *
- * CMD8 is optionally sent to determine the voltage range supported, and 
- * indirectly determine whether it is a version 1.x SD/non-SD card or 
+ * CMD8 is optionally sent to determine the voltage range supported, and
+ * indirectly determine whether it is a version 1.x SD/non-SD card or
  * version 2.x. I'll just ignore this for now.
  *
  * ACMD41 is repeatedly issued to initialise the card, until "in idle"
@@ -51,21 +50,21 @@
  * The SD SPI protocol is based on transactions made up of 8-bit words, with
  * the host starting every bus transaction by asserting the CS signal low. The
  * card always responds to commands, data blocks and errors.
- * 
- * The protocol supports a CRC, but by default it is off (except for the 
+ *
+ * The protocol supports a CRC, but by default it is off (except for the
  * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
- * I'll leave the CRC off I think! 
- * 
- * Standard capacity cards have variable data block sizes, whereas High 
+ * I'll leave the CRC off I think!
+ *
+ * Standard capacity cards have variable data block sizes, whereas High
  * Capacity cards fix the size of data block to 512 bytes. I'll therefore
  * just always use the Standard Capacity cards with a block size of 512 bytes.
  * This is set with CMD16.
  *
- * You can read and write single blocks (CMD17, CMD25) or multiple blocks 
+ * You can read and write single blocks (CMD17, CMD25) or multiple blocks
  * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
- * the card gets a read command, it responds with a response token, and then 
+ * the card gets a read command, it responds with a response token, and then
  * a data token or an error.
- * 
+ *
  * SPI Command Format
  * ------------------
  * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
@@ -81,7 +80,7 @@
  * SPI Response Format
  * -------------------
  * The main response format (R1) is a status byte (normally zero). Key flags:
- *  idle - 1 if the card is in an idle state/initialising 
+ *  idle - 1 if the card is in an idle state/initialising
  *  cmd  - 1 if an illegal command code was detected
  *
  *    +-------------------------------------------------+
@@ -93,7 +92,7 @@
  *
  * Data Response Token
  * -------------------
- * Every data block written to the card is acknowledged by a byte 
+ * Every data block written to the card is acknowledged by a byte
  * response token
  *
  * +----------------------+
@@ -108,22 +107,26 @@
  *
  * Block transfers have a byte header, followed by the data, followed
  * by a 16-bit CRC. In our case, the data will always be 512 bytes.
- *  
+ *
  * +------+---------+---------+- -  - -+---------+-----------+----------+
- * | 0xFE | data[0] | data[1] |        | data[n] | crc[15:8] | crc[7:0] | 
+ * | 0xFE | data[0] | data[1] |        | data[n] | crc[15:8] | crc[7:0] |
  * +------+---------+---------+- -  - -+---------+-----------+----------+
  */
- 
 #include "USBMSD_SD.h"
+#include "mbed_debug.h"
 
 #define SD_COMMAND_TIMEOUT 5000
 
+#define SD_DBG             0
+
 USBMSD_SD::USBMSD_SD(PinName mosi, PinName miso, PinName sclk, PinName cs) :
-   _spi(mosi, miso, sclk), _cs(cs) {
-      _cs = 1;
-      //no init
-      _status = 0x01;
-      connect();
+    _spi(mosi, miso, sclk), _cs(cs) {
+    _cs = 1;
+    
+    //no init
+    _status = 0x01;
+    
+    connect();
 }
 
 #define R1_IDLE_STATE           (1 << 0)
@@ -139,7 +142,6 @@
 //  - 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
@@ -147,90 +149,93 @@
 
 int USBMSD_SD::initialise_card() {
     // Set to 100kHz for initialisation, and clock card with cs = 1
-    _spi.frequency(100000); 
+    _spi.frequency(100000);
     _cs = 1;
-    for(int i=0; i<16; i++) {
+    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");
+    if (_cmd(0, 0) != R1_IDLE_STATE) {
+        debug("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) {
+    if (r == R1_IDLE_STATE) {
         return initialise_card_v2();
-    } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
+    } 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");
+        debug("Not in idle state after sending CMD8 (not an SD card?)\n");
         return SDCARD_FAIL;
     }
 }
 
 int USBMSD_SD::initialise_card_v1() {
-    for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
-        _cmd(55, 0); 
-        if(_cmd(41, 0) == 0) { 
+    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 SDCARD_V1;
         }
     }
-
-    fprintf(stderr, "Timeout waiting for v1.x card\n");
+    
+    debug("Timeout waiting for v1.x card\n");
     return SDCARD_FAIL;
 }
 
 int USBMSD_SD::initialise_card_v2() {
-    
-    for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
-        _cmd(55, 0); 
-        if(_cmd(41, 0) == 0) { 
+    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 SDCARD_V2;
         }
     }
-
-    fprintf(stderr, "Timeout waiting for v2.x card\n");
+    
+    debug("Timeout waiting for v2.x card\n");
     return SDCARD_FAIL;
 }
 
 int USBMSD_SD::disk_initialize() {
-
     int i = initialise_card();
-//    printf("init card = %d\n", i);
-//    printf("OK\n");
-
+    debug_if(SD_DBG, "init card = %d\n", i);
     _sectors = _sd_sectors();
-
+    
     // Set block length to 512 (CMD16)
-    if(_cmd(16, 512) != 0) {
-        fprintf(stderr, "Set 512-byte block timed out\n");
+    if (_cmd(16, 512) != 0) {
+        debug("Set 512-byte block timed out\n");
         return 1;
     }
-        
+    
     _spi.frequency(5000000); // Set to 5MHz for data transfer
+    
     // OK
     _status = 0x00;
+    
     return 0;
 }
 
-int USBMSD_SD::disk_write(const char *buffer, int block_number) {
+int USBMSD_SD::disk_write(const uint8_t *buffer, uint64_t block_number) {
     // set write address for single block (CMD24)
-    if(_cmd(24, block_number * 512) != 0) {
+    if (_cmd(24, block_number * cdv) != 0) {
         return 1;
     }
-
+    
     // send the data block
-    _write(buffer, 512);    
-    return 0;    
+    _write(buffer, 512);
+    return 0;
 }
 
-int USBMSD_SD::disk_read(char *buffer, int block_number) {        
+int USBMSD_SD::disk_read(uint8_t *buffer, uint64_t block_number) {
     // set read address for single block (CMD17)
-    if(_cmd(17, block_number * 512) != 0) {
+    if (_cmd(17, block_number * cdv) != 0) {
         return 1;
     }
     
@@ -241,13 +246,13 @@
 
 int USBMSD_SD::disk_status() { return _status; }
 int USBMSD_SD::disk_sync() { return 0; }
-int USBMSD_SD::disk_sectors() { return _sectors; }
+uint64_t USBMSD_SD::disk_sectors() { return _sectors; }
+
 
 // PRIVATE FUNCTIONS
-
 int USBMSD_SD::_cmd(int cmd, int arg) {
-    _cs = 0; 
-
+    _cs = 0;
+    
     // send a command
     _spi.write(0x40 | cmd);
     _spi.write(arg >> 24);
@@ -255,11 +260,11 @@
     _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++) {
+    for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
         int response = _spi.write(0xFF);
-        if(!(response & 0x80)) {
+        if (!(response & 0x80)) {
             _cs = 1;
             _spi.write(0xFF);
             return response;
@@ -270,8 +275,8 @@
     return -1; // timeout
 }
 int USBMSD_SD::_cmdx(int cmd, int arg) {
-    _cs = 0; 
-
+    _cs = 0;
+    
     // send a command
     _spi.write(0x40 | cmd);
     _spi.write(arg >> 24);
@@ -279,11 +284,11 @@
     _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++) {
+    for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
         int response = _spi.write(0xFF);
-        if(!(response & 0x80)) {
+        if (!(response & 0x80)) {
             return response;
         }
     }
@@ -294,7 +299,7 @@
 
 
 int USBMSD_SD::_cmd58() {
-    _cs = 0; 
+    _cs = 0;
     int arg = 0;
     
     // send a command
@@ -304,16 +309,15 @@
     _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++) {
+    for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
         int response = _spi.write(0xFF);
-        if(!(response & 0x80)) {
+        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;
@@ -325,7 +329,7 @@
 }
 
 int USBMSD_SD::_cmd8() {
-    _cs = 0; 
+    _cs = 0;
     
     // send a command
     _spi.write(0x40 | 8); // CMD8
@@ -334,18 +338,18 @@
     _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++) {
+    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];
+        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;
@@ -353,115 +357,117 @@
     return -1; // timeout
 }
 
-int USBMSD_SD::_read(char *buffer, int length) {
+int USBMSD_SD::_read(uint8_t *buffer, uint32_t length) {
     _cs = 0;
-
+    
     // read until start byte (0xFF)
-    while(_spi.write(0xFF) != 0xFE);
-
+    while (_spi.write(0xFF) != 0xFE);
+    
     // read data
-    for(int i=0; i<length; i++) {
+    for (int i = 0; i < length; i++) {
         buffer[i] = _spi.write(0xFF);
     }
     _spi.write(0xFF); // checksum
     _spi.write(0xFF);
-
-    _cs = 1;    
+    
+    _cs = 1;
     _spi.write(0xFF);
     return 0;
 }
 
-int USBMSD_SD::_write(const char *buffer, int length) {
+int USBMSD_SD::_write(const uint8_t*buffer, uint32_t length) {
     _cs = 0;
     
     // indicate start of block
     _spi.write(0xFE);
     
     // write the data
-    for(int i=0; i<length; i++) {
+    for (int i = 0; i < length; i++) {
         _spi.write(buffer[i]);
     }
     
     // write the checksum
-    _spi.write(0xFF); 
+    _spi.write(0xFF);
     _spi.write(0xFF);
-
-    // check the repsonse token
-    if((_spi.write(0xFF) & 0x1F) != 0x05) {
+    
+    // check the response token
+    if ((_spi.write(0xFF) & 0x1F) != 0x05) {
         _cs = 1;
-        _spi.write(0xFF);        
+        _spi.write(0xFF);
         return 1;
     }
-
+    
     // wait for write to finish
-    while(_spi.write(0xFF) == 0);
-
-    _cs = 1; 
+    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;
+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 USBMSD_SD::_sd_sectors() {
-
+uint64_t USBMSD_SD::_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) {
-        fprintf(stderr, "Didn't get a response from the disk\n");
+    if (_cmdx(9, 0) != 0) {
+        debug("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");
+    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);
-    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;
-    capacity = blocknr * block_len;
-
-    int blocks = capacity / 512;
+    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;
 }
-
-
-int USBMSD_SD::disk_size() {
-    return capacity;
-}
diff -r 923991b026e7 -r 055119ccf5a7 USBMSD_SD.h
--- a/USBMSD_SD.h	Sun Dec 11 15:52:35 2011 +0000
+++ b/USBMSD_SD.h	Mon Jan 21 10:40:05 2013 +0000
@@ -53,12 +53,13 @@
      */
     USBMSD_SD(PinName mosi, PinName miso, PinName sclk, PinName cs);
     virtual int disk_initialize();
-    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_read(uint8_t * buffer, uint64_t block_number);
+    virtual int disk_write(const uint8_t * buffer, uint64_t block_number);
     virtual int disk_sync();
-    virtual int disk_sectors();
-    virtual int disk_size();
+    virtual uint64_t disk_sectors();
+    
+    virtual uint64_t disk_size(){return _sectors*512;};
 
 protected:
 
@@ -70,16 +71,16 @@
     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;
+    int _read(uint8_t * buffer, uint32_t length);
+    int _write(const uint8_t *buffer, uint32_t length);
+    uint64_t _sd_sectors();
+    uint64_t _sectors;
     
-    int capacity;
-    int _status;
+    uint8_t _status;
     
     SPI _spi;
     DigitalOut _cs;
+    int cdv;
 };
 
 #endif