Kazuki Yamamoto / USBSDFileSystem

[ FORK ] USBSDFileSystem; fork from karelv/USBSDFilesystem

Dependents:   USBMSD_CDC_11U35test

Fork of USBSDFileSystem by karel.vanroye@...

USBSDFileSystem.cpp@2:b2034ad4951b, 2015-04-21 (annotated)

Committer:
k4zuki
Date:
Tue Apr 21 09:08:46 2015 +0000
Revision:
2:b2034ad4951b
Parent:
1:88089dd56f0e 
[ FIX ] matching latest USBMSD library(2015-Apr)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
karelv 0:c3d2e89ca30d 1 /* a copy of the SDFileSystem library...
karelv 0:c3d2e89ca30d 2 * but adapted for class 'USBSDFileSystem'!
karelv 0:c3d2e89ca30d 3 */
karelv 0:c3d2e89ca30d 4
karelv 0:c3d2e89ca30d 5 /* Introduction
karelv 0:c3d2e89ca30d 6 * ------------
karelv 0:c3d2e89ca30d 7 * SD and MMC cards support a number of interfaces, but common to them all
karelv 0:c3d2e89ca30d 8 * is one based on SPI. This is the one I'm implmenting because it means
karelv 0:c3d2e89ca30d 9 * it is much more portable even though not so performant, and we already
karelv 0:c3d2e89ca30d 10 * have the mbed SPI Interface!
karelv 0:c3d2e89ca30d 11 *
karelv 0:c3d2e89ca30d 12 * The main reference I'm using is Chapter 7, "SPI Mode" of:
karelv 0:c3d2e89ca30d 13 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
karelv 0:c3d2e89ca30d 14 *
karelv 0:c3d2e89ca30d 15 * SPI Startup
karelv 0:c3d2e89ca30d 16 * -----------
karelv 0:c3d2e89ca30d 17 * The SD card powers up in SD mode. The SPI interface mode is selected by
karelv 0:c3d2e89ca30d 18 * asserting CS low and sending the reset command (CMD0). The card will
karelv 0:c3d2e89ca30d 19 * respond with a (R1) response.
karelv 0:c3d2e89ca30d 20 *
karelv 0:c3d2e89ca30d 21 * CMD8 is optionally sent to determine the voltage range supported, and
karelv 0:c3d2e89ca30d 22 * indirectly determine whether it is a version 1.x SD/non-SD card or
karelv 0:c3d2e89ca30d 23 * version 2.x. I'll just ignore this for now.
karelv 0:c3d2e89ca30d 24 *
karelv 0:c3d2e89ca30d 25 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
karelv 0:c3d2e89ca30d 26 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
karelv 0:c3d2e89ca30d 27 *
karelv 0:c3d2e89ca30d 28 * You should also indicate whether the host supports High Capicity cards,
karelv 0:c3d2e89ca30d 29 * and check whether the card is high capacity - i'll also ignore this
karelv 0:c3d2e89ca30d 30 *
karelv 0:c3d2e89ca30d 31 * SPI Protocol
karelv 0:c3d2e89ca30d 32 * ------------
karelv 0:c3d2e89ca30d 33 * The SD SPI protocol is based on transactions made up of 8-bit words, with
karelv 0:c3d2e89ca30d 34 * the host starting every bus transaction by asserting the CS signal low. The
karelv 0:c3d2e89ca30d 35 * card always responds to commands, data blocks and errors.
karelv 0:c3d2e89ca30d 36 *
karelv 0:c3d2e89ca30d 37 * The protocol supports a CRC, but by default it is off (except for the
karelv 0:c3d2e89ca30d 38 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
karelv 0:c3d2e89ca30d 39 * I'll leave the CRC off I think!
karelv 0:c3d2e89ca30d 40 *
karelv 0:c3d2e89ca30d 41 * Standard capacity cards have variable data block sizes, whereas High
karelv 0:c3d2e89ca30d 42 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
karelv 0:c3d2e89ca30d 43 * just always use the Standard Capacity cards with a block size of 512 bytes.
karelv 0:c3d2e89ca30d 44 * This is set with CMD16.
karelv 0:c3d2e89ca30d 45 *
karelv 0:c3d2e89ca30d 46 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
karelv 0:c3d2e89ca30d 47 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
karelv 0:c3d2e89ca30d 48 * the card gets a read command, it responds with a response token, and then
karelv 0:c3d2e89ca30d 49 * a data token or an error.
karelv 0:c3d2e89ca30d 50 *
karelv 0:c3d2e89ca30d 51 * SPI Command Format
karelv 0:c3d2e89ca30d 52 * ------------------
karelv 0:c3d2e89ca30d 53 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
karelv 0:c3d2e89ca30d 54 *
karelv 0:c3d2e89ca30d 55 * +---------------+------------+------------+-----------+----------+--------------+
karelv 0:c3d2e89ca30d 56 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
karelv 0:c3d2e89ca30d 57 * +---------------+------------+------------+-----------+----------+--------------+
karelv 0:c3d2e89ca30d 58 *
karelv 0:c3d2e89ca30d 59 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
karelv 0:c3d2e89ca30d 60 *
karelv 0:c3d2e89ca30d 61 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
karelv 0:c3d2e89ca30d 62 *
karelv 0:c3d2e89ca30d 63 * SPI Response Format
karelv 0:c3d2e89ca30d 64 * -------------------
karelv 0:c3d2e89ca30d 65 * The main response format (R1) is a status byte (normally zero). Key flags:
karelv 0:c3d2e89ca30d 66 * idle - 1 if the card is in an idle state/initialising
karelv 0:c3d2e89ca30d 67 * cmd - 1 if an illegal command code was detected
karelv 0:c3d2e89ca30d 68 *
karelv 0:c3d2e89ca30d 69 * +-------------------------------------------------+
karelv 0:c3d2e89ca30d 70 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
karelv 0:c3d2e89ca30d 71 * +-------------------------------------------------+
karelv 0:c3d2e89ca30d 72 *
karelv 0:c3d2e89ca30d 73 * R1b is the same, except it is followed by a busy signal (zeros) until
karelv 0:c3d2e89ca30d 74 * the first non-zero byte when it is ready again.
karelv 0:c3d2e89ca30d 75 *
karelv 0:c3d2e89ca30d 76 * Data Response Token
karelv 0:c3d2e89ca30d 77 * -------------------
karelv 0:c3d2e89ca30d 78 * Every data block written to the card is acknowledged by a byte
karelv 0:c3d2e89ca30d 79 * response token
karelv 0:c3d2e89ca30d 80 *
karelv 0:c3d2e89ca30d 81 * +----------------------+
karelv 0:c3d2e89ca30d 82 * | xxx | 0 | status | 1 |
karelv 0:c3d2e89ca30d 83 * +----------------------+
karelv 0:c3d2e89ca30d 84 * 010 - OK!
karelv 0:c3d2e89ca30d 85 * 101 - CRC Error
karelv 0:c3d2e89ca30d 86 * 110 - Write Error
karelv 0:c3d2e89ca30d 87 *
karelv 0:c3d2e89ca30d 88 * Single Block Read and Write
karelv 0:c3d2e89ca30d 89 * ---------------------------
karelv 0:c3d2e89ca30d 90 *
karelv 0:c3d2e89ca30d 91 * Block transfers have a byte header, followed by the data, followed
karelv 0:c3d2e89ca30d 92 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
karelv 0:c3d2e89ca30d 93 *
karelv 0:c3d2e89ca30d 94 * +------+---------+---------+- - - -+---------+-----------+----------+
karelv 0:c3d2e89ca30d 95 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
karelv 0:c3d2e89ca30d 96 * +------+---------+---------+- - - -+---------+-----------+----------+
karelv 0:c3d2e89ca30d 97 */
karelv 0:c3d2e89ca30d 98 #include "USBSDFileSystem.h"
karelv 0:c3d2e89ca30d 99 #include "mbed_debug.h"
karelv 0:c3d2e89ca30d 100
karelv 0:c3d2e89ca30d 101 #define SD_COMMAND_TIMEOUT 5000
karelv 0:c3d2e89ca30d 102
karelv 0:c3d2e89ca30d 103 #define SD_DBG 0
karelv 0:c3d2e89ca30d 104
karelv 0:c3d2e89ca30d 105 USBSDFileSystem::USBSDFileSystem(const char *name, PinName mosi, PinName miso, PinName sclk, PinName cs) :
karelv 0:c3d2e89ca30d 106 USBFileSystem(name), _spi(mosi, miso, sclk), _cs(cs)
karelv 0:c3d2e89ca30d 107 {
karelv 0:c3d2e89ca30d 108 _cs = 1;
karelv 0:c3d2e89ca30d 109 //no init
karelv 0:c3d2e89ca30d 110 _status = 0x01;
karelv 0:c3d2e89ca30d 111 // wait (1);
karelv 1:88089dd56f0e 112 connect();
karelv 0:c3d2e89ca30d 113 }
karelv 0:c3d2e89ca30d 114
karelv 0:c3d2e89ca30d 115 #define R1_IDLE_STATE (1 << 0)
karelv 0:c3d2e89ca30d 116 #define R1_ERASE_RESET (1 << 1)
karelv 0:c3d2e89ca30d 117 #define R1_ILLEGAL_COMMAND (1 << 2)
karelv 0:c3d2e89ca30d 118 #define R1_COM_CRC_ERROR (1 << 3)
karelv 0:c3d2e89ca30d 119 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
karelv 0:c3d2e89ca30d 120 #define R1_ADDRESS_ERROR (1 << 5)
karelv 0:c3d2e89ca30d 121 #define R1_PARAMETER_ERROR (1 << 6)
karelv 0:c3d2e89ca30d 122
karelv 0:c3d2e89ca30d 123 // Types
karelv 0:c3d2e89ca30d 124 // - v1.x Standard Capacity
karelv 0:c3d2e89ca30d 125 // - v2.x Standard Capacity
karelv 0:c3d2e89ca30d 126 // - v2.x High Capacity
karelv 0:c3d2e89ca30d 127 // - Not recognised as an SD Card
karelv 0:c3d2e89ca30d 128 #define SDCARD_FAIL 0
karelv 0:c3d2e89ca30d 129 #define SDCARD_V1 1
karelv 0:c3d2e89ca30d 130 #define SDCARD_V2 2
karelv 0:c3d2e89ca30d 131 #define SDCARD_V2HC 3
karelv 0:c3d2e89ca30d 132
karelv 0:c3d2e89ca30d 133 int USBSDFileSystem::initialise_card() {
karelv 0:c3d2e89ca30d 134 // Set to 100kHz for initialisation, and clock card with cs = 1
karelv 0:c3d2e89ca30d 135 _spi.frequency(100000);
karelv 0:c3d2e89ca30d 136 _cs = 1;
karelv 0:c3d2e89ca30d 137 for (int i = 0; i < 16; i++) {
karelv 0:c3d2e89ca30d 138 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 139 }
karelv 0:c3d2e89ca30d 140
karelv 0:c3d2e89ca30d 141 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
karelv 0:c3d2e89ca30d 142 if (_cmd(0, 0) != R1_IDLE_STATE) {
karelv 0:c3d2e89ca30d 143 debug("No disk, or could not put SD card in to SPI idle state\n");
karelv 0:c3d2e89ca30d 144 return SDCARD_FAIL;
karelv 0:c3d2e89ca30d 145 }
karelv 0:c3d2e89ca30d 146
karelv 0:c3d2e89ca30d 147 // send CMD8 to determine whther it is ver 2.x
karelv 0:c3d2e89ca30d 148 int r = _cmd8();
karelv 0:c3d2e89ca30d 149 if (r == R1_IDLE_STATE) {
karelv 0:c3d2e89ca30d 150 return initialise_card_v2();
karelv 0:c3d2e89ca30d 151 } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
karelv 0:c3d2e89ca30d 152 return initialise_card_v1();
karelv 0:c3d2e89ca30d 153 } else {
karelv 0:c3d2e89ca30d 154 debug("Not in idle state after sending CMD8 (not an SD card?)\n");
karelv 0:c3d2e89ca30d 155 return SDCARD_FAIL;
karelv 0:c3d2e89ca30d 156 }
karelv 0:c3d2e89ca30d 157 }
karelv 0:c3d2e89ca30d 158
karelv 0:c3d2e89ca30d 159 int USBSDFileSystem::initialise_card_v1() {
karelv 0:c3d2e89ca30d 160 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
karelv 0:c3d2e89ca30d 161 _cmd(55, 0);
karelv 0:c3d2e89ca30d 162 if (_cmd(41, 0) == 0) {
karelv 0:c3d2e89ca30d 163 cdv = 512;
karelv 0:c3d2e89ca30d 164 debug_if(SD_DBG, "\n\rInit: SEDCARD_V1\n\r");
karelv 0:c3d2e89ca30d 165 return SDCARD_V1;
karelv 0:c3d2e89ca30d 166 }
karelv 0:c3d2e89ca30d 167 }
karelv 0:c3d2e89ca30d 168
karelv 0:c3d2e89ca30d 169 debug("Timeout waiting for v1.x card\n");
karelv 0:c3d2e89ca30d 170 return SDCARD_FAIL;
karelv 0:c3d2e89ca30d 171 }
karelv 0:c3d2e89ca30d 172
karelv 0:c3d2e89ca30d 173 int USBSDFileSystem::initialise_card_v2() {
karelv 0:c3d2e89ca30d 174 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
karelv 0:c3d2e89ca30d 175 wait_ms(50);
karelv 0:c3d2e89ca30d 176 _cmd58();
karelv 0:c3d2e89ca30d 177 _cmd(55, 0);
karelv 0:c3d2e89ca30d 178 if (_cmd(41, 0x40000000) == 0) {
karelv 0:c3d2e89ca30d 179 _cmd58();
karelv 0:c3d2e89ca30d 180 debug_if(SD_DBG, "\n\rInit: SDCARD_V2\n\r");
karelv 0:c3d2e89ca30d 181 cdv = 1;
karelv 0:c3d2e89ca30d 182 return SDCARD_V2;
karelv 0:c3d2e89ca30d 183 }
karelv 0:c3d2e89ca30d 184 }
karelv 0:c3d2e89ca30d 185
karelv 0:c3d2e89ca30d 186 debug("Timeout waiting for v2.x card\n");
karelv 0:c3d2e89ca30d 187 return SDCARD_FAIL;
karelv 0:c3d2e89ca30d 188 }
karelv 0:c3d2e89ca30d 189
karelv 0:c3d2e89ca30d 190 int USBSDFileSystem::disk_initialize() {
karelv 0:c3d2e89ca30d 191 int i = initialise_card();
karelv 0:c3d2e89ca30d 192 debug_if(SD_DBG, "init card = %d\n", i);
karelv 0:c3d2e89ca30d 193 _sectors = _sd_sectors();
karelv 0:c3d2e89ca30d 194
karelv 0:c3d2e89ca30d 195 // Set block length to 512 (CMD16)
karelv 0:c3d2e89ca30d 196 if (_cmd(16, 512) != 0) {
karelv 0:c3d2e89ca30d 197 debug("Set 512-byte block timed out\n");
karelv 0:c3d2e89ca30d 198 return 1;
karelv 0:c3d2e89ca30d 199 }
karelv 0:c3d2e89ca30d 200
karelv 0:c3d2e89ca30d 201 // _spi.frequency(1000000); // Set to 1MHz for data transfer
karelv 0:c3d2e89ca30d 202
karelv 0:c3d2e89ca30d 203 _spi.frequency(5000000); // Set to 5MHz for data transfer
karelv 0:c3d2e89ca30d 204
karelv 0:c3d2e89ca30d 205 // OK
karelv 0:c3d2e89ca30d 206 _status = 0x00;
karelv 0:c3d2e89ca30d 207
karelv 0:c3d2e89ca30d 208
karelv 0:c3d2e89ca30d 209
karelv 0:c3d2e89ca30d 210 return 0;
karelv 0:c3d2e89ca30d 211 }
karelv 0:c3d2e89ca30d 212
k4zuki 2:b2034ad4951b 213 //disk_read(uint8_t * buffer, uint64_t sector, uint8_t count)
k4zuki 2:b2034ad4951b 214 //_disk_write(const uint8_t * buffer, uint64_t sector, uint8_t count)
k4zuki 2:b2034ad4951b 215 int USBSDFileSystem::_disk_write(const uint8_t * buffer, uint64_t sector, uint8_t count=1) {
karelv 0:c3d2e89ca30d 216 // set write address for single block (CMD24)
k4zuki 2:b2034ad4951b 217 if (_cmd(24, sector * cdv) != 0) {
karelv 0:c3d2e89ca30d 218 return 1;
karelv 0:c3d2e89ca30d 219 }
karelv 0:c3d2e89ca30d 220
karelv 0:c3d2e89ca30d 221 // send the data block
karelv 0:c3d2e89ca30d 222 _write(buffer, 512);
karelv 0:c3d2e89ca30d 223 return 0;
karelv 0:c3d2e89ca30d 224 }
karelv 0:c3d2e89ca30d 225
k4zuki 2:b2034ad4951b 226 int USBSDFileSystem::disk_read(uint8_t * buffer, uint64_t sector, uint8_t count) {
karelv 0:c3d2e89ca30d 227 // set read address for single block (CMD17)
k4zuki 2:b2034ad4951b 228 if (_cmd(17, sector * cdv) != 0) {
karelv 0:c3d2e89ca30d 229 return 1;
karelv 0:c3d2e89ca30d 230 }
karelv 0:c3d2e89ca30d 231
karelv 0:c3d2e89ca30d 232 // receive the data
karelv 0:c3d2e89ca30d 233 _read(buffer, 512);
karelv 0:c3d2e89ca30d 234 return 0;
karelv 0:c3d2e89ca30d 235 }
karelv 0:c3d2e89ca30d 236
karelv 0:c3d2e89ca30d 237 int USBSDFileSystem::_disk_status() { return _status; }
karelv 0:c3d2e89ca30d 238 int USBSDFileSystem::disk_sync() { return 0; }
karelv 0:c3d2e89ca30d 239 uint64_t USBSDFileSystem::disk_sectors() { return _sectors; }
karelv 0:c3d2e89ca30d 240
karelv 0:c3d2e89ca30d 241
karelv 0:c3d2e89ca30d 242 // PRIVATE FUNCTIONS
karelv 0:c3d2e89ca30d 243 int USBSDFileSystem::_cmd(int cmd, int arg) {
karelv 0:c3d2e89ca30d 244 _cs = 0;
karelv 0:c3d2e89ca30d 245
karelv 0:c3d2e89ca30d 246 // send a command
karelv 0:c3d2e89ca30d 247 _spi.write(0x40 | cmd);
karelv 0:c3d2e89ca30d 248 _spi.write(arg >> 24);
karelv 0:c3d2e89ca30d 249 _spi.write(arg >> 16);
karelv 0:c3d2e89ca30d 250 _spi.write(arg >> 8);
karelv 0:c3d2e89ca30d 251 _spi.write(arg >> 0);
karelv 0:c3d2e89ca30d 252 _spi.write(0x95);
karelv 0:c3d2e89ca30d 253
karelv 0:c3d2e89ca30d 254 // wait for the repsonse (response[7] == 0)
karelv 0:c3d2e89ca30d 255 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
karelv 0:c3d2e89ca30d 256 int response = _spi.write(0xFF);
karelv 0:c3d2e89ca30d 257 if (!(response & 0x80)) {
karelv 0:c3d2e89ca30d 258 _cs = 1;
karelv 0:c3d2e89ca30d 259 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 260 return response;
karelv 0:c3d2e89ca30d 261 }
karelv 0:c3d2e89ca30d 262 }
karelv 0:c3d2e89ca30d 263 _cs = 1;
karelv 0:c3d2e89ca30d 264 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 265 return -1; // timeout
karelv 0:c3d2e89ca30d 266 }
karelv 0:c3d2e89ca30d 267 int USBSDFileSystem::_cmdx(int cmd, int arg) {
karelv 0:c3d2e89ca30d 268 _cs = 0;
karelv 0:c3d2e89ca30d 269
karelv 0:c3d2e89ca30d 270 // send a command
karelv 0:c3d2e89ca30d 271 _spi.write(0x40 | cmd);
karelv 0:c3d2e89ca30d 272 _spi.write(arg >> 24);
karelv 0:c3d2e89ca30d 273 _spi.write(arg >> 16);
karelv 0:c3d2e89ca30d 274 _spi.write(arg >> 8);
karelv 0:c3d2e89ca30d 275 _spi.write(arg >> 0);
karelv 0:c3d2e89ca30d 276 _spi.write(0x95);
karelv 0:c3d2e89ca30d 277
karelv 0:c3d2e89ca30d 278 // wait for the repsonse (response[7] == 0)
karelv 0:c3d2e89ca30d 279 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
karelv 0:c3d2e89ca30d 280 int response = _spi.write(0xFF);
karelv 0:c3d2e89ca30d 281 if (!(response & 0x80)) {
karelv 0:c3d2e89ca30d 282 return response;
karelv 0:c3d2e89ca30d 283 }
karelv 0:c3d2e89ca30d 284 }
karelv 0:c3d2e89ca30d 285 _cs = 1;
karelv 0:c3d2e89ca30d 286 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 287 return -1; // timeout
karelv 0:c3d2e89ca30d 288 }
karelv 0:c3d2e89ca30d 289
karelv 0:c3d2e89ca30d 290
karelv 0:c3d2e89ca30d 291 int USBSDFileSystem::_cmd58() {
karelv 0:c3d2e89ca30d 292 _cs = 0;
karelv 0:c3d2e89ca30d 293 int arg = 0;
karelv 0:c3d2e89ca30d 294
karelv 0:c3d2e89ca30d 295 // send a command
karelv 0:c3d2e89ca30d 296 _spi.write(0x40 | 58);
karelv 0:c3d2e89ca30d 297 _spi.write(arg >> 24);
karelv 0:c3d2e89ca30d 298 _spi.write(arg >> 16);
karelv 0:c3d2e89ca30d 299 _spi.write(arg >> 8);
karelv 0:c3d2e89ca30d 300 _spi.write(arg >> 0);
karelv 0:c3d2e89ca30d 301 _spi.write(0x95);
karelv 0:c3d2e89ca30d 302
karelv 0:c3d2e89ca30d 303 // wait for the repsonse (response[7] == 0)
karelv 0:c3d2e89ca30d 304 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
karelv 0:c3d2e89ca30d 305 int response = _spi.write(0xFF);
karelv 0:c3d2e89ca30d 306 if (!(response & 0x80)) {
karelv 0:c3d2e89ca30d 307 int ocr = _spi.write(0xFF) << 24;
karelv 0:c3d2e89ca30d 308 ocr |= _spi.write(0xFF) << 16;
karelv 0:c3d2e89ca30d 309 ocr |= _spi.write(0xFF) << 8;
karelv 0:c3d2e89ca30d 310 ocr |= _spi.write(0xFF) << 0;
karelv 0:c3d2e89ca30d 311 _cs = 1;
karelv 0:c3d2e89ca30d 312 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 313 return response;
karelv 0:c3d2e89ca30d 314 }
karelv 0:c3d2e89ca30d 315 }
karelv 0:c3d2e89ca30d 316 _cs = 1;
karelv 0:c3d2e89ca30d 317 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 318 return -1; // timeout
karelv 0:c3d2e89ca30d 319 }
karelv 0:c3d2e89ca30d 320
karelv 0:c3d2e89ca30d 321 int USBSDFileSystem::_cmd8() {
karelv 0:c3d2e89ca30d 322 _cs = 0;
karelv 0:c3d2e89ca30d 323
karelv 0:c3d2e89ca30d 324 // send a command
karelv 0:c3d2e89ca30d 325 _spi.write(0x40 | 8); // CMD8
karelv 0:c3d2e89ca30d 326 _spi.write(0x00); // reserved
karelv 0:c3d2e89ca30d 327 _spi.write(0x00); // reserved
karelv 0:c3d2e89ca30d 328 _spi.write(0x01); // 3.3v
karelv 0:c3d2e89ca30d 329 _spi.write(0xAA); // check pattern
karelv 0:c3d2e89ca30d 330 _spi.write(0x87); // crc
karelv 0:c3d2e89ca30d 331
karelv 0:c3d2e89ca30d 332 // wait for the repsonse (response[7] == 0)
karelv 0:c3d2e89ca30d 333 for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
karelv 0:c3d2e89ca30d 334 char response[5];
karelv 0:c3d2e89ca30d 335 response[0] = _spi.write(0xFF);
karelv 0:c3d2e89ca30d 336 if (!(response[0] & 0x80)) {
karelv 0:c3d2e89ca30d 337 for (int j = 1; j < 5; j++) {
karelv 0:c3d2e89ca30d 338 response[i] = _spi.write(0xFF);
karelv 0:c3d2e89ca30d 339 }
karelv 0:c3d2e89ca30d 340 _cs = 1;
karelv 0:c3d2e89ca30d 341 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 342 return response[0];
karelv 0:c3d2e89ca30d 343 }
karelv 0:c3d2e89ca30d 344 }
karelv 0:c3d2e89ca30d 345 _cs = 1;
karelv 0:c3d2e89ca30d 346 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 347 return -1; // timeout
karelv 0:c3d2e89ca30d 348 }
karelv 0:c3d2e89ca30d 349
karelv 0:c3d2e89ca30d 350 int USBSDFileSystem::_read(uint8_t *buffer, uint32_t length) {
karelv 0:c3d2e89ca30d 351 _cs = 0;
karelv 0:c3d2e89ca30d 352
karelv 0:c3d2e89ca30d 353 // read until start byte (0xFF)
karelv 0:c3d2e89ca30d 354 while (_spi.write(0xFF) != 0xFE);
karelv 0:c3d2e89ca30d 355
karelv 0:c3d2e89ca30d 356 // read data
karelv 0:c3d2e89ca30d 357 for (int i = 0; i < length; i++) {
karelv 0:c3d2e89ca30d 358 buffer[i] = _spi.write(0xFF);
karelv 0:c3d2e89ca30d 359 }
karelv 0:c3d2e89ca30d 360 _spi.write(0xFF); // checksum
karelv 0:c3d2e89ca30d 361 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 362
karelv 0:c3d2e89ca30d 363 _cs = 1;
karelv 0:c3d2e89ca30d 364 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 365 return 0;
karelv 0:c3d2e89ca30d 366 }
karelv 0:c3d2e89ca30d 367
karelv 0:c3d2e89ca30d 368 int USBSDFileSystem::_write(const uint8_t*buffer, uint32_t length) {
karelv 0:c3d2e89ca30d 369 _cs = 0;
karelv 0:c3d2e89ca30d 370
karelv 0:c3d2e89ca30d 371 // indicate start of block
karelv 0:c3d2e89ca30d 372 _spi.write(0xFE);
karelv 0:c3d2e89ca30d 373
karelv 0:c3d2e89ca30d 374 // write the data
karelv 0:c3d2e89ca30d 375 for (int i = 0; i < length; i++) {
karelv 0:c3d2e89ca30d 376 _spi.write(buffer[i]);
karelv 0:c3d2e89ca30d 377 }
karelv 0:c3d2e89ca30d 378
karelv 0:c3d2e89ca30d 379 // write the checksum
karelv 0:c3d2e89ca30d 380 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 381 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 382
karelv 0:c3d2e89ca30d 383 // check the response token
karelv 0:c3d2e89ca30d 384 if ((_spi.write(0xFF) & 0x1F) != 0x05) {
karelv 0:c3d2e89ca30d 385 _cs = 1;
karelv 0:c3d2e89ca30d 386 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 387 return 1;
karelv 0:c3d2e89ca30d 388 }
karelv 0:c3d2e89ca30d 389
karelv 0:c3d2e89ca30d 390 // wait for write to finish
karelv 0:c3d2e89ca30d 391 while (_spi.write(0xFF) == 0);
karelv 0:c3d2e89ca30d 392
karelv 0:c3d2e89ca30d 393 _cs = 1;
karelv 0:c3d2e89ca30d 394 _spi.write(0xFF);
karelv 0:c3d2e89ca30d 395 return 0;
karelv 0:c3d2e89ca30d 396 }
karelv 0:c3d2e89ca30d 397
karelv 0:c3d2e89ca30d 398 static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
karelv 0:c3d2e89ca30d 399 uint32_t bits = 0;
karelv 0:c3d2e89ca30d 400 uint32_t size = 1 + msb - lsb;
karelv 0:c3d2e89ca30d 401 for (int i = 0; i < size; i++) {
karelv 0:c3d2e89ca30d 402 uint32_t position = lsb + i;
karelv 0:c3d2e89ca30d 403 uint32_t byte = 15 - (position >> 3);
karelv 0:c3d2e89ca30d 404 uint32_t bit = position & 0x7;
karelv 0:c3d2e89ca30d 405 uint32_t value = (data[byte] >> bit) & 1;
karelv 0:c3d2e89ca30d 406 bits |= value << i;
karelv 0:c3d2e89ca30d 407 }
karelv 0:c3d2e89ca30d 408 return bits;
karelv 0:c3d2e89ca30d 409 }
karelv 0:c3d2e89ca30d 410
karelv 0:c3d2e89ca30d 411 uint64_t USBSDFileSystem::_sd_sectors() {
karelv 0:c3d2e89ca30d 412 uint32_t c_size, c_size_mult, read_bl_len;
karelv 0:c3d2e89ca30d 413 uint32_t block_len, mult, blocknr, capacity;
karelv 0:c3d2e89ca30d 414 uint32_t hc_c_size;
karelv 0:c3d2e89ca30d 415 uint64_t blocks;
karelv 0:c3d2e89ca30d 416
karelv 0:c3d2e89ca30d 417 // CMD9, Response R2 (R1 byte + 16-byte block read)
karelv 0:c3d2e89ca30d 418 if (_cmdx(9, 0) != 0) {
karelv 0:c3d2e89ca30d 419 debug("Didn't get a response from the disk\n");
karelv 0:c3d2e89ca30d 420 return 0;
karelv 0:c3d2e89ca30d 421 }
karelv 0:c3d2e89ca30d 422
karelv 0:c3d2e89ca30d 423 uint8_t csd[16];
karelv 0:c3d2e89ca30d 424 if (_read(csd, 16) != 0) {
karelv 0:c3d2e89ca30d 425 debug("Couldn't read csd response from disk\n");
karelv 0:c3d2e89ca30d 426 return 0;
karelv 0:c3d2e89ca30d 427 }
karelv 0:c3d2e89ca30d 428
karelv 0:c3d2e89ca30d 429 // csd_structure : csd[127:126]
karelv 0:c3d2e89ca30d 430 // c_size : csd[73:62]
karelv 0:c3d2e89ca30d 431 // c_size_mult : csd[49:47]
karelv 0:c3d2e89ca30d 432 // read_bl_len : csd[83:80] - the *maximum* read block length
karelv 0:c3d2e89ca30d 433
karelv 0:c3d2e89ca30d 434 int csd_structure = ext_bits(csd, 127, 126);
karelv 0:c3d2e89ca30d 435
karelv 0:c3d2e89ca30d 436 switch (csd_structure) {
karelv 0:c3d2e89ca30d 437 case 0:
karelv 0:c3d2e89ca30d 438 cdv = 512;
karelv 0:c3d2e89ca30d 439 c_size = ext_bits(csd, 73, 62);
karelv 0:c3d2e89ca30d 440 c_size_mult = ext_bits(csd, 49, 47);
karelv 0:c3d2e89ca30d 441 read_bl_len = ext_bits(csd, 83, 80);
karelv 0:c3d2e89ca30d 442
karelv 0:c3d2e89ca30d 443 block_len = 1 << read_bl_len;
karelv 0:c3d2e89ca30d 444 mult = 1 << (c_size_mult + 2);
karelv 0:c3d2e89ca30d 445 blocknr = (c_size + 1) * mult;
karelv 0:c3d2e89ca30d 446 capacity = blocknr * block_len;
karelv 0:c3d2e89ca30d 447 blocks = capacity / 512;
karelv 0:c3d2e89ca30d 448 debug_if(SD_DBG, "\n\rSDCard\n\rc_size: %d \n\rcapacity: %ld \n\rsectors: %lld\n\r", c_size, capacity, blocks);
karelv 0:c3d2e89ca30d 449 break;
karelv 0:c3d2e89ca30d 450
karelv 0:c3d2e89ca30d 451 case 1:
karelv 0:c3d2e89ca30d 452 cdv = 1;
karelv 0:c3d2e89ca30d 453 hc_c_size = ext_bits(csd, 63, 48);
karelv 0:c3d2e89ca30d 454 blocks = (hc_c_size+1)*1024;
karelv 0:c3d2e89ca30d 455 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);
karelv 0:c3d2e89ca30d 456 break;
karelv 0:c3d2e89ca30d 457
karelv 0:c3d2e89ca30d 458 default:
karelv 0:c3d2e89ca30d 459 debug("CSD struct unsupported\r\n");
karelv 0:c3d2e89ca30d 460 return 0;
karelv 0:c3d2e89ca30d 461 };
karelv 0:c3d2e89ca30d 462 return blocks;
karelv 0:c3d2e89ca30d 463 }