USBMSD: Use SDFileSystem class and USB non-blocking
Fork of USBMSD_SD by
Revision 3:8c7810e6b858, committed 2014-02-15
- Comitter:
- Olivier
- Date:
- Sat Feb 15 12:49:23 2014 +0000
- Parent:
- 2:055119ccf5a7
- Commit message:
- Use SDFileSystem class instead of duplicating the code into the new class.; ; Required; - http://mbed.org/users/mbed_official/code/USBDevice/pull-request/3; - http://mbed.org/users/mbed_official/code/SDFileSystem/pull-request/1
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 055119ccf5a7 -r 8c7810e6b858 USBMSD_SD.cpp --- a/USBMSD_SD.cpp Mon Jan 21 10:40:05 2013 +0000 +++ b/USBMSD_SD.cpp Sat Feb 15 12:49:23 2014 +0000 @@ -19,455 +19,15 @@ * 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 - * have the mbed SPI Interface! - * - * 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 - * 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 - * version 2.x. I'll just ignore this for now. - * - * ACMD41 is repeatedly issued to initialise the card, until "in idle" - * (bit 0) of the R1 response goes to '0', indicating it is initialised. - * - * You should also indicate whether the host supports High Capicity cards, - * and check whether the card is high capacity - i'll also ignore this - * - * SPI Protocol - * ------------ - * 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 - * 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 - * 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 - * (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 - * a data token or an error. - * - * SPI Command Format - * ------------------ - * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC. - * - * +---------------+------------+------------+-----------+----------+--------------+ - * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 | - * +---------------+------------+------------+-----------+----------+--------------+ - * - * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95) - * - * All Application Specific commands shall be preceded with APP_CMD (CMD55). - * - * 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 - * cmd - 1 if an illegal command code was detected - * - * +-------------------------------------------------+ - * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle | - * +-------------------------------------------------+ - * - * R1b is the same, except it is followed by a busy signal (zeros) until - * the first non-zero byte when it is ready again. - * - * Data Response Token - * ------------------- - * Every data block written to the card is acknowledged by a byte - * response token - * - * +----------------------+ - * | xxx | 0 | status | 1 | - * +----------------------+ - * 010 - OK! - * 101 - CRC Error - * 110 - Write Error - * - * Single Block Read and Write - * --------------------------- - * - * 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] | - * +------+---------+---------+- - - -+---------+-----------+----------+ - */ + #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(); -} - -#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 USBMSD_SD::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) { - 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) { - return initialise_card_v2(); - } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) { - return initialise_card_v1(); - } else { - 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) { - cdv = 512; - debug_if(SD_DBG, "\n\rInit: SEDCARD_V1\n\r"); - return SDCARD_V1; - } - } - - debug("Timeout waiting for v1.x card\n"); - return SDCARD_FAIL; -} +USBMSD_SD::USBMSD_SD(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) : + SDFileSystem(mosi, miso, sclk, cs, name) { + // Set to 5MHz for SD data transfer + set_transfer_sck(5000000); -int USBMSD_SD::initialise_card_v2() { - 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; - } - } - - debug("Timeout waiting for v2.x card\n"); - return SDCARD_FAIL; -} - -int USBMSD_SD::disk_initialize() { - int i = initialise_card(); - debug_if(SD_DBG, "init card = %d\n", i); - _sectors = _sd_sectors(); - - // Set block length to 512 (CMD16) - 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 uint8_t *buffer, uint64_t block_number) { - // set write address for single block (CMD24) - if (_cmd(24, block_number * cdv) != 0) { - return 1; - } - - // send the data block - _write(buffer, 512); - return 0; -} - -int USBMSD_SD::disk_read(uint8_t *buffer, uint64_t block_number) { - // set read address for single block (CMD17) - if (_cmd(17, block_number * cdv) != 0) { - return 1; - } - - // receive the data - _read(buffer, 512); - return 0; -} - -int USBMSD_SD::disk_status() { return _status; } -int USBMSD_SD::disk_sync() { return 0; } -uint64_t USBMSD_SD::disk_sectors() { return _sectors; } - - -// PRIVATE FUNCTIONS -int USBMSD_SD::_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 + // Call USBMSD::connect(bool blocking) + connect(false); } -int USBMSD_SD::_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 USBMSD_SD::_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; - _cs = 1; - _spi.write(0xFF); - return response; - } - } - _cs = 1; - _spi.write(0xFF); - return -1; // timeout -} - -int USBMSD_SD::_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 USBMSD_SD::_read(uint8_t *buffer, uint32_t 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 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++) { - _spi.write(buffer[i]); - } - - // write the checksum - _spi.write(0xFF); - _spi.write(0xFF); - - // check the response 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 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; -} - -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) { - debug("Didn't get a response from the disk\n"); - return 0; - } - - 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); - - 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; -}
diff -r 055119ccf5a7 -r 8c7810e6b858 USBMSD_SD.h --- a/USBMSD_SD.h Mon Jan 21 10:40:05 2013 +0000 +++ b/USBMSD_SD.h Sat Feb 15 12:49:23 2014 +0000 @@ -25,6 +25,7 @@ #include "mbed.h" #include "USBMSD.h" +#include "SDFileSystem.h" /** Use the SDcard as mass storage device using the USBMSD class * @@ -40,7 +41,7 @@ * * @endcode */ -class USBMSD_SD : public USBMSD { +class USBMSD_SD : public SDFileSystem, public USBMSD { public: /** Create the File System for accessing an SD Card using SPI @@ -51,36 +52,15 @@ * @param cs DigitalOut pin used as SD Card chip select * @param name The name used to access the virtual filesystem */ - USBMSD_SD(PinName mosi, PinName miso, PinName sclk, PinName cs); - virtual int disk_initialize(); - 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 uint64_t disk_sectors(); + USBMSD_SD(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name); + + virtual uint64_t disk_size() { return _sectors*512; }; + virtual int disk_status() { return _is_initialized?0:1; }; - virtual uint64_t disk_size(){return _sectors*512;}; - -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(uint8_t * buffer, uint32_t length); - int _write(const uint8_t *buffer, uint32_t length); - uint64_t _sd_sectors(); - uint64_t _sectors; - - uint8_t _status; - - SPI _spi; - DigitalOut _cs; - int cdv; + virtual int disk_read(uint8_t * data, uint64_t block) { return SDFileSystem::disk_read(data, block); }; + virtual int disk_write(const uint8_t * data, uint64_t block) { return SDFileSystem::disk_write(data, block); }; + virtual int disk_initialize() { return SDFileSystem::disk_initialize(); }; + virtual uint64_t disk_sectors() { return SDFileSystem::disk_sectors(); }; }; #endif