SDHC Library SDCard

Dependents:   CameraC1098_picture CameraC1098_GPS_different_Lib

Committer:
atommota
Date:
Fri Jul 01 21:18:58 2011 +0000
Revision:
2:5e21e22ef223
Parent:
0:aefb7d370128

        

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atommota 0:aefb7d370128 1 /* mbed SDFileSystem Library, for providing file access to SD cards
atommota 0:aefb7d370128 2 * Copyright (c) 2008-2010, sford
atommota 0:aefb7d370128 3 *
atommota 0:aefb7d370128 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
atommota 0:aefb7d370128 5 * of this software and associated documentation files (the "Software"), to deal
atommota 0:aefb7d370128 6 * in the Software without restriction, including without limitation the rights
atommota 0:aefb7d370128 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
atommota 0:aefb7d370128 8 * copies of the Software, and to permit persons to whom the Software is
atommota 0:aefb7d370128 9 * furnished to do so, subject to the following conditions:
atommota 0:aefb7d370128 10 *
atommota 0:aefb7d370128 11 * The above copyright notice and this permission notice shall be included in
atommota 0:aefb7d370128 12 * all copies or substantial portions of the Software.
atommota 0:aefb7d370128 13 *
atommota 0:aefb7d370128 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
atommota 0:aefb7d370128 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
atommota 0:aefb7d370128 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
atommota 0:aefb7d370128 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
atommota 0:aefb7d370128 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
atommota 0:aefb7d370128 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
atommota 0:aefb7d370128 20 * THE SOFTWARE.
atommota 0:aefb7d370128 21 */
atommota 0:aefb7d370128 22
atommota 0:aefb7d370128 23 /* Introduction
atommota 0:aefb7d370128 24 * ------------
atommota 0:aefb7d370128 25 * SD and MMC cards support a number of interfaces, but common to them all
atommota 0:aefb7d370128 26 * is one based on SPI. This is the one I'm implmenting because it means
atommota 0:aefb7d370128 27 * it is much more portable even though not so performant, and we already
atommota 0:aefb7d370128 28 * have the mbed SPI Interface!
atommota 0:aefb7d370128 29 *
atommota 0:aefb7d370128 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
atommota 0:aefb7d370128 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
atommota 0:aefb7d370128 32 *
atommota 0:aefb7d370128 33 * SPI Startup
atommota 0:aefb7d370128 34 * -----------
atommota 0:aefb7d370128 35 * The SD card powers up in SD mode. The SPI interface mode is selected by
atommota 0:aefb7d370128 36 * asserting CS low and sending the reset command (CMD0). The card will
atommota 0:aefb7d370128 37 * respond with a (R1) response.
atommota 0:aefb7d370128 38 *
atommota 0:aefb7d370128 39 * CMD8 is optionally sent to determine the voltage range supported, and
atommota 0:aefb7d370128 40 * indirectly determine whether it is a version 1.x SD/non-SD card or
atommota 0:aefb7d370128 41 * version 2.x. I'll just ignore this for now.
atommota 0:aefb7d370128 42 *
atommota 0:aefb7d370128 43 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
atommota 0:aefb7d370128 44 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
atommota 0:aefb7d370128 45 *
atommota 0:aefb7d370128 46 * You should also indicate whether the host supports High Capicity cards,
atommota 0:aefb7d370128 47 * and check whether the card is high capacity - i'll also ignore this
atommota 0:aefb7d370128 48 *
atommota 0:aefb7d370128 49 * SPI Protocol
atommota 0:aefb7d370128 50 * ------------
atommota 0:aefb7d370128 51 * The SD SPI protocol is based on transactions made up of 8-bit words, with
atommota 0:aefb7d370128 52 * the host starting every bus transaction by asserting the CS signal low. The
atommota 0:aefb7d370128 53 * card always responds to commands, data blocks and errors.
atommota 0:aefb7d370128 54 *
atommota 0:aefb7d370128 55 * The protocol supports a CRC, but by default it is off (except for the
atommota 0:aefb7d370128 56 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
atommota 0:aefb7d370128 57 * I'll leave the CRC off I think!
atommota 0:aefb7d370128 58 *
atommota 0:aefb7d370128 59 * Standard capacity cards have variable data block sizes, whereas High
atommota 0:aefb7d370128 60 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
atommota 0:aefb7d370128 61 * just always use the Standard Capacity cards with a block size of 512 bytes.
atommota 0:aefb7d370128 62 * This is set with CMD16.
atommota 0:aefb7d370128 63 *
atommota 0:aefb7d370128 64 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
atommota 0:aefb7d370128 65 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
atommota 0:aefb7d370128 66 * the card gets a read command, it responds with a response token, and then
atommota 0:aefb7d370128 67 * a data token or an error.
atommota 0:aefb7d370128 68 *
atommota 0:aefb7d370128 69 * SPI Command Format
atommota 0:aefb7d370128 70 * ------------------
atommota 0:aefb7d370128 71 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
atommota 0:aefb7d370128 72 *
atommota 0:aefb7d370128 73 * +---------------+------------+------------+-----------+----------+--------------+
atommota 0:aefb7d370128 74 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
atommota 0:aefb7d370128 75 * +---------------+------------+------------+-----------+----------+--------------+
atommota 0:aefb7d370128 76 *
atommota 0:aefb7d370128 77 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
atommota 0:aefb7d370128 78 *
atommota 0:aefb7d370128 79 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
atommota 0:aefb7d370128 80 *
atommota 0:aefb7d370128 81 * SPI Response Format
atommota 0:aefb7d370128 82 * -------------------
atommota 0:aefb7d370128 83 * The main response format (R1) is a status byte (normally zero). Key flags:
atommota 0:aefb7d370128 84 * idle - 1 if the card is in an idle state/initialising
atommota 0:aefb7d370128 85 * cmd - 1 if an illegal command code was detected
atommota 0:aefb7d370128 86 *
atommota 0:aefb7d370128 87 * +-------------------------------------------------+
atommota 0:aefb7d370128 88 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
atommota 0:aefb7d370128 89 * +-------------------------------------------------+
atommota 0:aefb7d370128 90 *
atommota 0:aefb7d370128 91 * R1b is the same, except it is followed by a busy signal (zeros) until
atommota 0:aefb7d370128 92 * the first non-zero byte when it is ready again.
atommota 0:aefb7d370128 93 *
atommota 0:aefb7d370128 94 * Data Response Token
atommota 0:aefb7d370128 95 * -------------------
atommota 0:aefb7d370128 96 * Every data block written to the card is acknowledged by a byte
atommota 0:aefb7d370128 97 * response token
atommota 0:aefb7d370128 98 *
atommota 0:aefb7d370128 99 * +----------------------+
atommota 0:aefb7d370128 100 * | xxx | 0 | status | 1 |
atommota 0:aefb7d370128 101 * +----------------------+
atommota 0:aefb7d370128 102 * 010 - OK!
atommota 0:aefb7d370128 103 * 101 - CRC Error
atommota 0:aefb7d370128 104 * 110 - Write Error
atommota 0:aefb7d370128 105 *
atommota 0:aefb7d370128 106 * Single Block Read and Write
atommota 0:aefb7d370128 107 * ---------------------------
atommota 0:aefb7d370128 108 *
atommota 0:aefb7d370128 109 * Block transfers have a byte header, followed by the data, followed
atommota 0:aefb7d370128 110 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
atommota 0:aefb7d370128 111 *
atommota 0:aefb7d370128 112 * +------+---------+---------+- - - -+---------+-----------+----------+
atommota 0:aefb7d370128 113 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
atommota 0:aefb7d370128 114 * +------+---------+---------+- - - -+---------+-----------+----------+
atommota 0:aefb7d370128 115 */
atommota 0:aefb7d370128 116
atommota 0:aefb7d370128 117 /*
atommota 0:aefb7d370128 118 * Comment: Changes for SDHC support till 32GB
atommota 0:aefb7d370128 119 * Name: KB
atommota 0:aefb7d370128 120 * Date: 07/24/2010
atommota 0:aefb7d370128 121 * Release: 0.1
atommota 0:aefb7d370128 122 */
atommota 0:aefb7d370128 123
atommota 0:aefb7d370128 124 #include "SDHCFileSystem.h"
atommota 0:aefb7d370128 125
atommota 0:aefb7d370128 126 #define DEBUG
atommota 0:aefb7d370128 127 #define SD_COMMAND_TIMEOUT 5000
atommota 0:aefb7d370128 128
atommota 0:aefb7d370128 129
atommota 0:aefb7d370128 130 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
atommota 0:aefb7d370128 131 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
atommota 0:aefb7d370128 132 _cs = 1;
atommota 0:aefb7d370128 133 }
atommota 0:aefb7d370128 134
atommota 0:aefb7d370128 135 #define R1_IDLE_STATE (1 << 0)
atommota 0:aefb7d370128 136 #define R1_ERASE_RESET (1 << 1)
atommota 0:aefb7d370128 137 #define R1_ILLEGAL_COMMAND (1 << 2)
atommota 0:aefb7d370128 138 #define R1_COM_CRC_ERROR (1 << 3)
atommota 0:aefb7d370128 139 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
atommota 0:aefb7d370128 140 #define R1_ADDRESS_ERROR (1 << 5)
atommota 0:aefb7d370128 141 #define R1_PARAMETER_ERROR (1 << 6)
atommota 0:aefb7d370128 142
atommota 0:aefb7d370128 143 // Types
atommota 0:aefb7d370128 144 // - v1.x Standard Capacity
atommota 0:aefb7d370128 145 // - v2.x Standard Capacity
atommota 0:aefb7d370128 146 // - v2.x High Capacity
atommota 0:aefb7d370128 147 // - Not recognised as an SD Card
atommota 0:aefb7d370128 148
atommota 0:aefb7d370128 149 #define SDCARD_FAIL 0
atommota 0:aefb7d370128 150 #define SDCARD_V1 1
atommota 0:aefb7d370128 151 #define SDCARD_V2 2
atommota 0:aefb7d370128 152 #define SDCARD_V2HC 3
atommota 0:aefb7d370128 153
atommota 0:aefb7d370128 154 int SDFileSystem::initialise_card() {
atommota 0:aefb7d370128 155 // Set to 100kHz for initialisation, and clock card with cs = 1
atommota 0:aefb7d370128 156 _spi.frequency(100000);
atommota 0:aefb7d370128 157 _cs = 1;
atommota 0:aefb7d370128 158 for(int i=0; i<16; i++) {
atommota 0:aefb7d370128 159 _spi.write(0xFF);
atommota 0:aefb7d370128 160 }
atommota 0:aefb7d370128 161
atommota 0:aefb7d370128 162 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
atommota 0:aefb7d370128 163 if(_cmd(0, 0) != R1_IDLE_STATE) {
atommota 0:aefb7d370128 164 fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
atommota 0:aefb7d370128 165 return SDCARD_FAIL;
atommota 0:aefb7d370128 166 }
atommota 0:aefb7d370128 167
atommota 0:aefb7d370128 168 // send CMD8 to determine whther it is ver 2.x
atommota 0:aefb7d370128 169 int r = _cmd8();
atommota 0:aefb7d370128 170 if(r == R1_IDLE_STATE) {
atommota 0:aefb7d370128 171 return initialise_card_v2();
atommota 0:aefb7d370128 172 } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
atommota 0:aefb7d370128 173 return initialise_card_v1();
atommota 0:aefb7d370128 174 } else {
atommota 0:aefb7d370128 175 fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
atommota 0:aefb7d370128 176 return SDCARD_FAIL;
atommota 0:aefb7d370128 177 }
atommota 0:aefb7d370128 178 }
atommota 0:aefb7d370128 179
atommota 0:aefb7d370128 180 int SDFileSystem::initialise_card_v1() {
atommota 0:aefb7d370128 181 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
atommota 0:aefb7d370128 182 _cmd(55, 0);
atommota 0:aefb7d370128 183 if(_cmd(41, 0) == 0) {
atommota 0:aefb7d370128 184 cdv = 512;
atommota 0:aefb7d370128 185 #ifdef DEBUG
atommota 0:aefb7d370128 186 printf("\n\rInit: SEDCARD_V1\n\r");
atommota 0:aefb7d370128 187 #endif
atommota 0:aefb7d370128 188 return SDCARD_V1;
atommota 0:aefb7d370128 189 }
atommota 0:aefb7d370128 190 }
atommota 0:aefb7d370128 191
atommota 0:aefb7d370128 192 fprintf(stderr, "Timeout waiting for v1.x card\n");
atommota 0:aefb7d370128 193 return SDCARD_FAIL;
atommota 0:aefb7d370128 194 }
atommota 0:aefb7d370128 195
atommota 0:aefb7d370128 196 int SDFileSystem::initialise_card_v2() {
atommota 0:aefb7d370128 197
atommota 0:aefb7d370128 198 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
atommota 0:aefb7d370128 199 wait_ms(50);
atommota 0:aefb7d370128 200 _cmd58();
atommota 0:aefb7d370128 201 _cmd(55, 0);
atommota 0:aefb7d370128 202 if(_cmd(41, 0x40000000) == 0) {
atommota 0:aefb7d370128 203 _cmd58();
atommota 0:aefb7d370128 204 #ifdef DEBUG
atommota 0:aefb7d370128 205 printf("\n\rInit: SDCARD_V2\n\r");
atommota 0:aefb7d370128 206 #endif
atommota 0:aefb7d370128 207 cdv = 1;
atommota 0:aefb7d370128 208 return SDCARD_V2;
atommota 0:aefb7d370128 209 }
atommota 0:aefb7d370128 210 }
atommota 0:aefb7d370128 211
atommota 0:aefb7d370128 212 fprintf(stderr, "Timeout waiting for v2.x card\n");
atommota 0:aefb7d370128 213 return SDCARD_FAIL;
atommota 0:aefb7d370128 214 }
atommota 0:aefb7d370128 215
atommota 0:aefb7d370128 216 int SDFileSystem::disk_initialize() {
atommota 0:aefb7d370128 217
atommota 0:aefb7d370128 218 int i = initialise_card();
atommota 0:aefb7d370128 219 #ifdef DEBUG
atommota 0:aefb7d370128 220 printf("init card = %d\n", i);
atommota 0:aefb7d370128 221 #endif
atommota 0:aefb7d370128 222 _sectors = _sd_sectors();
atommota 0:aefb7d370128 223
atommota 0:aefb7d370128 224 // Set block length to 512 (CMD16)
atommota 0:aefb7d370128 225 if(_cmd(16, 512) != 0) {
atommota 0:aefb7d370128 226 fprintf(stderr, "Set 512-byte block timed out\n");
atommota 0:aefb7d370128 227 return 1;
atommota 0:aefb7d370128 228 }
atommota 0:aefb7d370128 229
atommota 0:aefb7d370128 230 _spi.frequency(1000000); // Set to 1MHz for data transfer
atommota 0:aefb7d370128 231 return 0;
atommota 0:aefb7d370128 232 }
atommota 0:aefb7d370128 233
atommota 0:aefb7d370128 234 int SDFileSystem::disk_write(const char *buffer, int block_number) {
atommota 0:aefb7d370128 235 // set write address for single block (CMD24)
atommota 0:aefb7d370128 236 if(_cmd(24, block_number * cdv) != 0) {
atommota 0:aefb7d370128 237 return 1;
atommota 0:aefb7d370128 238 }
atommota 0:aefb7d370128 239
atommota 0:aefb7d370128 240 // send the data block
atommota 0:aefb7d370128 241 _write(buffer, 512);
atommota 0:aefb7d370128 242 return 0;
atommota 0:aefb7d370128 243 }
atommota 0:aefb7d370128 244
atommota 0:aefb7d370128 245 int SDFileSystem::disk_read(char *buffer, int block_number) {
atommota 0:aefb7d370128 246 // set read address for single block (CMD17)
atommota 0:aefb7d370128 247 if(_cmd(17, block_number * cdv) != 0) {
atommota 0:aefb7d370128 248 return 1;
atommota 0:aefb7d370128 249 }
atommota 0:aefb7d370128 250
atommota 0:aefb7d370128 251 // receive the data
atommota 0:aefb7d370128 252 _read(buffer, 512);
atommota 0:aefb7d370128 253 return 0;
atommota 0:aefb7d370128 254 }
atommota 0:aefb7d370128 255
atommota 0:aefb7d370128 256 int SDFileSystem::disk_status() { return 0; }
atommota 0:aefb7d370128 257 int SDFileSystem::disk_sync() { return 0; }
atommota 0:aefb7d370128 258 int SDFileSystem::disk_sectors() { return _sectors; }
atommota 0:aefb7d370128 259
atommota 0:aefb7d370128 260 // PRIVATE FUNCTIONS
atommota 0:aefb7d370128 261
atommota 0:aefb7d370128 262 int SDFileSystem::_cmd(int cmd, int arg) {
atommota 0:aefb7d370128 263 _cs = 0;
atommota 0:aefb7d370128 264
atommota 0:aefb7d370128 265 // send a command
atommota 0:aefb7d370128 266 _spi.write(0x40 | cmd);
atommota 0:aefb7d370128 267 _spi.write(arg >> 24);
atommota 0:aefb7d370128 268 _spi.write(arg >> 16);
atommota 0:aefb7d370128 269 _spi.write(arg >> 8);
atommota 0:aefb7d370128 270 _spi.write(arg >> 0);
atommota 0:aefb7d370128 271 _spi.write(0x95);
atommota 0:aefb7d370128 272
atommota 0:aefb7d370128 273 // wait for the repsonse (response[7] == 0)
atommota 0:aefb7d370128 274 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
atommota 0:aefb7d370128 275 int response = _spi.write(0xFF);
atommota 0:aefb7d370128 276 if(!(response & 0x80)) {
atommota 0:aefb7d370128 277 _cs = 1;
atommota 0:aefb7d370128 278 _spi.write(0xFF);
atommota 0:aefb7d370128 279 return response;
atommota 0:aefb7d370128 280 }
atommota 0:aefb7d370128 281 }
atommota 0:aefb7d370128 282 _cs = 1;
atommota 0:aefb7d370128 283 _spi.write(0xFF);
atommota 0:aefb7d370128 284 return -1; // timeout
atommota 0:aefb7d370128 285 }
atommota 0:aefb7d370128 286 int SDFileSystem::_cmdx(int cmd, int arg) {
atommota 0:aefb7d370128 287 _cs = 0;
atommota 0:aefb7d370128 288
atommota 0:aefb7d370128 289 // send a command
atommota 0:aefb7d370128 290 _spi.write(0x40 | cmd);
atommota 0:aefb7d370128 291 _spi.write(arg >> 24);
atommota 0:aefb7d370128 292 _spi.write(arg >> 16);
atommota 0:aefb7d370128 293 _spi.write(arg >> 8);
atommota 0:aefb7d370128 294 _spi.write(arg >> 0);
atommota 0:aefb7d370128 295 _spi.write(0x95);
atommota 0:aefb7d370128 296
atommota 0:aefb7d370128 297 // wait for the repsonse (response[7] == 0)
atommota 0:aefb7d370128 298 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
atommota 0:aefb7d370128 299 int response = _spi.write(0xFF);
atommota 0:aefb7d370128 300 if(!(response & 0x80)) {
atommota 0:aefb7d370128 301 return response;
atommota 0:aefb7d370128 302 }
atommota 0:aefb7d370128 303 }
atommota 0:aefb7d370128 304 _cs = 1;
atommota 0:aefb7d370128 305 _spi.write(0xFF);
atommota 0:aefb7d370128 306 return -1; // timeout
atommota 0:aefb7d370128 307 }
atommota 0:aefb7d370128 308
atommota 0:aefb7d370128 309
atommota 0:aefb7d370128 310 int SDFileSystem::_cmd58() {
atommota 0:aefb7d370128 311 _cs = 0;
atommota 0:aefb7d370128 312 int arg = 0;
atommota 0:aefb7d370128 313
atommota 0:aefb7d370128 314 // send a command
atommota 0:aefb7d370128 315 _spi.write(0x40 | 58);
atommota 0:aefb7d370128 316 _spi.write(arg >> 24);
atommota 0:aefb7d370128 317 _spi.write(arg >> 16);
atommota 0:aefb7d370128 318 _spi.write(arg >> 8);
atommota 0:aefb7d370128 319 _spi.write(arg >> 0);
atommota 0:aefb7d370128 320 _spi.write(0x95);
atommota 0:aefb7d370128 321
atommota 0:aefb7d370128 322 // wait for the repsonse (response[7] == 0)
atommota 0:aefb7d370128 323 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
atommota 0:aefb7d370128 324 int response = _spi.write(0xFF);
atommota 0:aefb7d370128 325 if(!(response & 0x80)) {
atommota 0:aefb7d370128 326 int ocr = _spi.write(0xFF) << 24;
atommota 0:aefb7d370128 327 ocr |= _spi.write(0xFF) << 16;
atommota 0:aefb7d370128 328 ocr |= _spi.write(0xFF) << 8;
atommota 0:aefb7d370128 329 ocr |= _spi.write(0xFF) << 0;
atommota 0:aefb7d370128 330 // printf("OCR = 0x%08X\n", ocr);
atommota 0:aefb7d370128 331 _cs = 1;
atommota 0:aefb7d370128 332 _spi.write(0xFF);
atommota 0:aefb7d370128 333 return response;
atommota 0:aefb7d370128 334 }
atommota 0:aefb7d370128 335 }
atommota 0:aefb7d370128 336 _cs = 1;
atommota 0:aefb7d370128 337 _spi.write(0xFF);
atommota 0:aefb7d370128 338 return -1; // timeout
atommota 0:aefb7d370128 339 }
atommota 0:aefb7d370128 340
atommota 0:aefb7d370128 341 int SDFileSystem::_cmd8() {
atommota 0:aefb7d370128 342 _cs = 0;
atommota 0:aefb7d370128 343
atommota 0:aefb7d370128 344 // send a command
atommota 0:aefb7d370128 345 _spi.write(0x40 | 8); // CMD8
atommota 0:aefb7d370128 346 _spi.write(0x00); // reserved
atommota 0:aefb7d370128 347 _spi.write(0x00); // reserved
atommota 0:aefb7d370128 348 _spi.write(0x01); // 3.3v
atommota 0:aefb7d370128 349 _spi.write(0xAA); // check pattern
atommota 0:aefb7d370128 350 _spi.write(0x87); // crc
atommota 0:aefb7d370128 351
atommota 0:aefb7d370128 352 // wait for the repsonse (response[7] == 0)
atommota 0:aefb7d370128 353 for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
atommota 0:aefb7d370128 354 char response[5];
atommota 0:aefb7d370128 355 response[0] = _spi.write(0xFF);
atommota 0:aefb7d370128 356 if(!(response[0] & 0x80)) {
atommota 0:aefb7d370128 357 for(int j=1; j<5; j++) {
atommota 0:aefb7d370128 358 response[i] = _spi.write(0xFF);
atommota 0:aefb7d370128 359 }
atommota 0:aefb7d370128 360 _cs = 1;
atommota 0:aefb7d370128 361 _spi.write(0xFF);
atommota 0:aefb7d370128 362 return response[0];
atommota 0:aefb7d370128 363 }
atommota 0:aefb7d370128 364 }
atommota 0:aefb7d370128 365 _cs = 1;
atommota 0:aefb7d370128 366 _spi.write(0xFF);
atommota 0:aefb7d370128 367 return -1; // timeout
atommota 0:aefb7d370128 368 }
atommota 0:aefb7d370128 369
atommota 0:aefb7d370128 370 int SDFileSystem::_read(char *buffer, int length) {
atommota 0:aefb7d370128 371 _cs = 0;
atommota 0:aefb7d370128 372
atommota 0:aefb7d370128 373 // read until start byte (0xFF)
atommota 0:aefb7d370128 374 while(_spi.write(0xFF) != 0xFE);
atommota 0:aefb7d370128 375
atommota 0:aefb7d370128 376 // read data
atommota 0:aefb7d370128 377 for(int i=0; i<length; i++) {
atommota 0:aefb7d370128 378 buffer[i] = _spi.write(0xFF);
atommota 0:aefb7d370128 379 }
atommota 0:aefb7d370128 380 _spi.write(0xFF); // checksum
atommota 0:aefb7d370128 381 _spi.write(0xFF);
atommota 0:aefb7d370128 382
atommota 0:aefb7d370128 383 _cs = 1;
atommota 0:aefb7d370128 384 _spi.write(0xFF);
atommota 0:aefb7d370128 385 return 0;
atommota 0:aefb7d370128 386 }
atommota 0:aefb7d370128 387
atommota 0:aefb7d370128 388 int SDFileSystem::_write(const char *buffer, int length) {
atommota 0:aefb7d370128 389 _cs = 0;
atommota 0:aefb7d370128 390
atommota 0:aefb7d370128 391 // indicate start of block
atommota 0:aefb7d370128 392 _spi.write(0xFE);
atommota 0:aefb7d370128 393
atommota 0:aefb7d370128 394 // write the data
atommota 0:aefb7d370128 395 for(int i=0; i<length; i++) {
atommota 0:aefb7d370128 396 _spi.write(buffer[i]);
atommota 0:aefb7d370128 397 }
atommota 0:aefb7d370128 398
atommota 0:aefb7d370128 399 // write the checksum
atommota 0:aefb7d370128 400 _spi.write(0xFF);
atommota 0:aefb7d370128 401 _spi.write(0xFF);
atommota 0:aefb7d370128 402
atommota 0:aefb7d370128 403 // check the repsonse token
atommota 0:aefb7d370128 404 if((_spi.write(0xFF) & 0x1F) != 0x05) {
atommota 0:aefb7d370128 405 _cs = 1;
atommota 0:aefb7d370128 406 _spi.write(0xFF);
atommota 0:aefb7d370128 407 return 1;
atommota 0:aefb7d370128 408 }
atommota 0:aefb7d370128 409
atommota 0:aefb7d370128 410 // wait for write to finish
atommota 0:aefb7d370128 411 while(_spi.write(0xFF) == 0);
atommota 0:aefb7d370128 412
atommota 0:aefb7d370128 413 _cs = 1;
atommota 0:aefb7d370128 414 _spi.write(0xFF);
atommota 0:aefb7d370128 415 return 0;
atommota 0:aefb7d370128 416 }
atommota 0:aefb7d370128 417
atommota 0:aefb7d370128 418 static int ext_bits(char *data, int msb, int lsb) {
atommota 0:aefb7d370128 419 int bits = 0;
atommota 0:aefb7d370128 420 int size = 1 + msb - lsb;
atommota 0:aefb7d370128 421 for(int i=0; i<size; i++) {
atommota 0:aefb7d370128 422 int position = lsb + i;
atommota 0:aefb7d370128 423 int byte = 15 - (position >> 3);
atommota 0:aefb7d370128 424 int bit = position & 0x7;
atommota 0:aefb7d370128 425 int value = (data[byte] >> bit) & 1;
atommota 0:aefb7d370128 426 bits |= value << i;
atommota 0:aefb7d370128 427 }
atommota 0:aefb7d370128 428 return bits;
atommota 0:aefb7d370128 429 }
atommota 0:aefb7d370128 430
atommota 0:aefb7d370128 431 int SDFileSystem::_sd_sectors() {
atommota 0:aefb7d370128 432
atommota 0:aefb7d370128 433 int c_size, c_size_mult, read_bl_len;
atommota 0:aefb7d370128 434 int block_len, mult, blocknr, capacity;
atommota 0:aefb7d370128 435 int blocks, hc_c_size;
atommota 0:aefb7d370128 436 uint64_t hc_capacity;
atommota 0:aefb7d370128 437
atommota 0:aefb7d370128 438 // CMD9, Response R2 (R1 byte + 16-byte block read)
atommota 0:aefb7d370128 439 if(_cmdx(9, 0) != 0) {
atommota 0:aefb7d370128 440 fprintf(stderr, "Didn't get a response from the disk\n");
atommota 0:aefb7d370128 441 return 0;
atommota 0:aefb7d370128 442 }
atommota 0:aefb7d370128 443
atommota 0:aefb7d370128 444 char csd[16];
atommota 0:aefb7d370128 445 if(_read(csd, 16) != 0) {
atommota 0:aefb7d370128 446 fprintf(stderr, "Couldn't read csd response from disk\n");
atommota 0:aefb7d370128 447 return 0;
atommota 0:aefb7d370128 448 }
atommota 0:aefb7d370128 449
atommota 0:aefb7d370128 450 // csd_structure : csd[127:126]
atommota 0:aefb7d370128 451 // c_size : csd[73:62]
atommota 0:aefb7d370128 452 // c_size_mult : csd[49:47]
atommota 0:aefb7d370128 453 // read_bl_len : csd[83:80] - the *maximum* read block length
atommota 0:aefb7d370128 454
atommota 0:aefb7d370128 455 int csd_structure = ext_bits(csd, 127, 126);
atommota 0:aefb7d370128 456
atommota 0:aefb7d370128 457 #ifdef DEBUG
atommota 0:aefb7d370128 458 printf("\n\rCSD_STRUCT = %d\n", csd_structure);
atommota 0:aefb7d370128 459 #endif
atommota 0:aefb7d370128 460
atommota 0:aefb7d370128 461 switch (csd_structure){
atommota 0:aefb7d370128 462 case 0:
atommota 0:aefb7d370128 463 cdv = 512;
atommota 0:aefb7d370128 464 c_size = ext_bits(csd, 73, 62);
atommota 0:aefb7d370128 465 c_size_mult = ext_bits(csd, 49, 47);
atommota 0:aefb7d370128 466 read_bl_len = ext_bits(csd, 83, 80);
atommota 0:aefb7d370128 467
atommota 0:aefb7d370128 468 block_len = 1 << read_bl_len;
atommota 0:aefb7d370128 469 mult = 1 << (c_size_mult + 2);
atommota 0:aefb7d370128 470 blocknr = (c_size + 1) * mult;
atommota 0:aefb7d370128 471 capacity = blocknr * block_len;
atommota 0:aefb7d370128 472 blocks = capacity / 512;
atommota 0:aefb7d370128 473 #ifdef DEBUG
atommota 0:aefb7d370128 474 printf("\n\rSDCard\n\rc_size: %.4X \n\rcapacity: %.ld \n\rsectors: %d\n\r", c_size, capacity, blocks);
atommota 0:aefb7d370128 475 #endif
atommota 0:aefb7d370128 476 break;
atommota 0:aefb7d370128 477
atommota 0:aefb7d370128 478 case 1:
atommota 0:aefb7d370128 479 cdv = 1;
atommota 0:aefb7d370128 480 hc_c_size = ext_bits(csd, 63, 48);
atommota 0:aefb7d370128 481 int hc_read_bl_len = ext_bits(csd, 83, 80);
atommota 0:aefb7d370128 482 hc_capacity = hc_c_size+1;
atommota 0:aefb7d370128 483 blocks = (hc_c_size+1)*1024;
atommota 0:aefb7d370128 484 #ifdef DEBUG
atommota 0:aefb7d370128 485 printf("\n\rSDHC Card \n\rhc_c_size: %.4X \n\rcapacity: %.lld \n\rsectors: %d\n\r", hc_c_size, hc_capacity*512*1024, blocks);
atommota 0:aefb7d370128 486 #endif
atommota 0:aefb7d370128 487 break;
atommota 0:aefb7d370128 488
atommota 0:aefb7d370128 489 default:
atommota 0:aefb7d370128 490 fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
atommota 0:aefb7d370128 491 return 0;
atommota 0:aefb7d370128 492 break;
atommota 0:aefb7d370128 493 };
atommota 0:aefb7d370128 494 return blocks;
atommota 0:aefb7d370128 495 }