Revision 2:849162a1207f, committed 2009-12-14

Comitter:

simon

Date:

Mon Dec 14 22:32:28 2009 +0000

Parent:

1:2dec995d53f8

Child:

3:68ef62208d4d

Commit message:

Changed in this revision

--- a/SDFileSystem.cpp	Mon Dec 14 20:31:54 2009 +0000
+++ b/SDFileSystem.cpp	Mon Dec 14 22:32:28 2009 +0000
@@ -104,6 +104,14 @@
       _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)
+
 int SDFileSystem::disk_initialize() {
 
     _spi.frequency(100000); // Set to 100kHz for initialisation
@@ -115,11 +123,20 @@
     }
 
     // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
-    if(_cmd(0, 0) != 0x01) { 
-        fprintf(stderr, "Not in idle state\n");
+    if(_cmd(0, 0) != R1_IDLE_STATE) { 
+        fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
         return 1;
     }
-    
+
+    int r = _cmd8();
+    if(r == R1_IDLE_STATE) {
+        printf("SD version 2.x\n");
+    } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
+        printf("SD version 1.x\n");
+    } else {
+        error("Unknown SD version\n");
+    }
+        
     // ACMD41 to give host capacity support (repeat until not busy)
     // ACMD41 is application specific command, so we send APP_CMD (CMD55) beforehand
     for(int i=0;; i++) {
@@ -133,6 +150,8 @@
         }    
     }
 
+    printf("OK\n");
+
     _sectors = _sd_sectors();
 
     // Set block length to 512 (CMD16)
@@ -198,6 +217,35 @@
     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;
 

--- a/SDFileSystem.h	Mon Dec 14 20:31:54 2009 +0000
+++ b/SDFileSystem.h	Mon Dec 14 22:32:28 2009 +0000
@@ -1,56 +1,58 @@
-/* mbed Microcontroller Library - SDFileSystem
- * Copyright (c) 2008-2009, sford
- */
-
-#ifndef SDFILESYSTEM_H
-#define SDFILESYSTEM_H
-
-#include "mbed.h"
-#include "FATFileSystem.h"
-
-/* Class: SDFileSystem
- *  Access the filesystem on an SD Card using SPI
- *
- * Example:
- * > SDFileSystem sd(p5, p6, p7, p12, "sd");
- * > 
- * > int main() {
- * >     FILE *fp = fopen("/sd/myfile.txt", "w");
- * >     fprintf(fp, "Hello World!\n");
- * >     fclose(fp);
- * > }
- */
-class SDFileSystem : public FATFileSystem {
-public:
-
-	/* Constructor: SDFileSystem
-	 *  Create the File System for accessing an SD Card using SPI
-	 *
-	 * Variables:
-	 *  mosi - SPI mosi pin connected to SD Card
-	 *  miso - SPI miso pin conencted to SD Card
-	 *  sclk - SPI sclk pin connected to SD Card
-	 *  cs   - DigitalOut pin used as SD Card chip select
-   *  name - The name used to access the filesystem
-	 */
-	SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name);
-	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_sync();
-	virtual int disk_sectors();
-
-protected:
-
-	int _cmd(int cmd, int arg);
-	int _read(char *buffer, int length);
-	int _write(const char *buffer, int length);
-	int _sd_sectors();
-	int _sectors;
-	
-	SPI _spi;
-	DigitalOut _cs;	 
-};
-
-#endif
+/* mbed Microcontroller Library - SDFileSystem
+ * Copyright (c) 2008-2009, sford
+ */
+
+#ifndef SDFILESYSTEM_H
+#define SDFILESYSTEM_H
+
+#include "mbed.h"
+#include "FATFileSystem.h"
+
+/* Class: SDFileSystem
+ *  Access the filesystem on an SD Card using SPI
+ *
+ * Example:
+ * > SDFileSystem sd(p5, p6, p7, p12, "sd");
+ * > 
+ * > int main() {
+ * >     FILE *fp = fopen("/sd/myfile.txt", "w");
+ * >     fprintf(fp, "Hello World!\n");
+ * >     fclose(fp);
+ * > }
+ */
+class SDFileSystem : public FATFileSystem {
+public:
+
+    /* Constructor: SDFileSystem
+     *  Create the File System for accessing an SD Card using SPI
+     *
+     * Variables:
+     *  mosi - SPI mosi pin connected to SD Card
+     *  miso - SPI miso pin conencted to SD Card
+     *  sclk - SPI sclk pin connected to SD Card
+     *  cs   - DigitalOut pin used as SD Card chip select
+   *  name - The name used to access the filesystem
+     */
+    SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name);
+    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_sync();
+    virtual int disk_sectors();
+
+protected:
+
+    int _cmd(int cmd, int arg);
+    int _cmd8();
+    
+    int _read(char *buffer, int length);
+    int _write(const char *buffer, int length);
+    int _sd_sectors();
+    int _sectors;
+    
+    SPI _spi;
+    DigitalOut _cs;     
+};
+
+#endif