SDBlock.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2012 ARM Limited
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00020  * SOFTWARE.
00021  */
00022 #ifndef MBED_SDBlock_H
00023 #define MBED_SDBlock_H
00024 
00025 #include "mbed.h"
00026 #include <stdint.h>
00027 
00028 /** Access the filesystem on an SD Card using SPI
00029  *
00030  * @code
00031  * #include "mbed.h"
00032  * #include "SDBlock.h"
00033  *
00034  * SDBlock sd(p5, p6, p7, p12, "sd"); // mosi, miso, sclk, cs
00035  *
00036  * int main() {
00037  *     FILE *fp = fopen("/sd/myfile.txt", "w");
00038  *     fprintf(fp, "Hello World!\n");
00039  *     fclose(fp);
00040  * }
00041  */
00042 class SDBlock {
00043 public:
00044 
00045     /** Create the File System for accessing an SD Card using SPI
00046      *
00047      * @param mosi SPI mosi pin connected to SD Card
00048      * @param miso SPI miso pin conencted to SD Card
00049      * @param sclk SPI sclk pin connected to SD Card
00050      * @param cs   DigitalOut pin used as SD Card chip select
00051      * @param name The name used to access the virtual filesystem
00052      */
00053     SDBlock(PinName mosi, PinName miso, PinName sclk, PinName cs);
00054     virtual int disk_initialize();
00055     virtual int disk_status();
00056     virtual int disk_read(uint8_t* buffer, uint32_t block_number, uint32_t count);
00057     virtual int disk_write(const uint8_t* buffer, uint32_t block_number, uint32_t count);
00058     virtual int disk_sync();
00059     virtual uint32_t disk_sectors();
00060 
00061 protected:
00062 
00063     int _cmd(int cmd, int arg);
00064     int _cmdx(int cmd, int arg);
00065     int _cmd8();
00066     int _cmd58();
00067     int initialise_card();
00068     int initialise_card_v1();
00069     int initialise_card_v2();
00070 
00071     int _read(uint8_t * buffer, uint32_t length);
00072     int _write(const uint8_t *buffer, uint32_t length);
00073     uint32_t _sd_sectors();
00074     uint32_t _sectors;
00075 
00076     void set_init_sck(uint32_t sck) { _init_sck = sck; }
00077     // Note: The highest SPI clock rate is 20 MHz for MMC and 25 MHz for SD
00078     void set_transfer_sck(uint32_t sck) { _transfer_sck = sck; }
00079     uint32_t _init_sck;
00080     uint32_t _transfer_sck;
00081 
00082     SPI _spi;
00083     DigitalOut _cs;
00084     int cdv;
00085     int _is_initialized;
00086 };
00087 
00088 #endif