Tick Tock / SDHCFileSystem

.

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SDHCFileSystem.cpp@0:89846a293813, 2012-11-29 (annotated)

Committer:
TickTock
Date:
Thu Nov 29 12:18:20 2012 +0000
Revision:
0:89846a293813
fixed build warnings

Who changed what in which revision?

UserRevisionLine numberNew contents of line
TickTock 0:89846a293813 1 /* mbed SDFileSystem Library, for providing file access to SD cards
TickTock 0:89846a293813 2 * Copyright (c) 2008-2010, sford
TickTock 0:89846a293813 3 *
TickTock 0:89846a293813 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
TickTock 0:89846a293813 5 * of this software and associated documentation files (the "Software"), to deal
TickTock 0:89846a293813 6 * in the Software without restriction, including without limitation the rights
TickTock 0:89846a293813 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
TickTock 0:89846a293813 8 * copies of the Software, and to permit persons to whom the Software is
TickTock 0:89846a293813 9 * furnished to do so, subject to the following conditions:
TickTock 0:89846a293813 10 *
TickTock 0:89846a293813 11 * The above copyright notice and this permission notice shall be included in
TickTock 0:89846a293813 12 * all copies or substantial portions of the Software.
TickTock 0:89846a293813 13 *
TickTock 0:89846a293813 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
TickTock 0:89846a293813 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
TickTock 0:89846a293813 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
TickTock 0:89846a293813 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
TickTock 0:89846a293813 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
TickTock 0:89846a293813 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
TickTock 0:89846a293813 20 * THE SOFTWARE.
TickTock 0:89846a293813 21 */
TickTock 0:89846a293813 22
TickTock 0:89846a293813 23 /* Introduction
TickTock 0:89846a293813 24 * ------------
TickTock 0:89846a293813 25 * SD and MMC cards support a number of interfaces, but common to them all
TickTock 0:89846a293813 26 * is one based on SPI. This is the one I'm implmenting because it means
TickTock 0:89846a293813 27 * it is much more portable even though not so performant, and we already
TickTock 0:89846a293813 28 * have the mbed SPI Interface!
TickTock 0:89846a293813 29 *
TickTock 0:89846a293813 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
TickTock 0:89846a293813 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
TickTock 0:89846a293813 32 *
TickTock 0:89846a293813 33 * SPI Startup
TickTock 0:89846a293813 34 * -----------
TickTock 0:89846a293813 35 * The SD card powers up in SD mode. The SPI interface mode is selected by
TickTock 0:89846a293813 36 * asserting CS low and sending the reset command (CMD0). The card will
TickTock 0:89846a293813 37 * respond with a (R1) response.
TickTock 0:89846a293813 38 *
TickTock 0:89846a293813 39 * CMD8 is optionally sent to determine the voltage range supported, and
TickTock 0:89846a293813 40 * indirectly determine whether it is a version 1.x SD/non-SD card or
TickTock 0:89846a293813 41 * version 2.x. I'll just ignore this for now.
TickTock 0:89846a293813 42 *
TickTock 0:89846a293813 43 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
TickTock 0:89846a293813 44 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
TickTock 0:89846a293813 45 *
TickTock 0:89846a293813 46 * You should also indicate whether the host supports High Capicity cards,
TickTock 0:89846a293813 47 * and check whether the card is high capacity - i'll also ignore this
TickTock 0:89846a293813 48 *
TickTock 0:89846a293813 49 * SPI Protocol
TickTock 0:89846a293813 50 * ------------
TickTock 0:89846a293813 51 * The SD SPI protocol is based on transactions made up of 8-bit words, with
TickTock 0:89846a293813 52 * the host starting every bus transaction by asserting the CS signal low. The
TickTock 0:89846a293813 53 * card always responds to commands, data blocks and errors.
TickTock 0:89846a293813 54 *
TickTock 0:89846a293813 55 * The protocol supports a CRC, but by default it is off (except for the
TickTock 0:89846a293813 56 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
TickTock 0:89846a293813 57 * I'll leave the CRC off I think!
TickTock 0:89846a293813 58 *
TickTock 0:89846a293813 59 * Standard capacity cards have variable data block sizes, whereas High
TickTock 0:89846a293813 60 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
TickTock 0:89846a293813 61 * just always use the Standard Capacity cards with a block size of 512 bytes.
TickTock 0:89846a293813 62 * This is set with CMD16.
TickTock 0:89846a293813 63 *
TickTock 0:89846a293813 64 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
TickTock 0:89846a293813 65 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
TickTock 0:89846a293813 66 * the card gets a read command, it responds with a response token, and then
TickTock 0:89846a293813 67 * a data token or an error.
TickTock 0:89846a293813 68 *
TickTock 0:89846a293813 69 * SPI Command Format
TickTock 0:89846a293813 70 * ------------------
TickTock 0:89846a293813 71 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
TickTock 0:89846a293813 72 *
TickTock 0:89846a293813 73 * +---------------+------------+------------+-----------+----------+--------------+
TickTock 0:89846a293813 74 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
TickTock 0:89846a293813 75 * +---------------+------------+------------+-----------+----------+--------------+
TickTock 0:89846a293813 76 *
TickTock 0:89846a293813 77 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
TickTock 0:89846a293813 78 *
TickTock 0:89846a293813 79 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
TickTock 0:89846a293813 80 *
TickTock 0:89846a293813 81 * SPI Response Format
TickTock 0:89846a293813 82 * -------------------
TickTock 0:89846a293813 83 * The main response format (R1) is a status byte (normally zero). Key flags:
TickTock 0:89846a293813 84 * idle - 1 if the card is in an idle state/initialising
TickTock 0:89846a293813 85 * cmd - 1 if an illegal command code was detected
TickTock 0:89846a293813 86 *
TickTock 0:89846a293813 87 * +-------------------------------------------------+
TickTock 0:89846a293813 88 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
TickTock 0:89846a293813 89 * +-------------------------------------------------+
TickTock 0:89846a293813 90 *
TickTock 0:89846a293813 91 * R1b is the same, except it is followed by a busy signal (zeros) until
TickTock 0:89846a293813 92 * the first non-zero byte when it is ready again.
TickTock 0:89846a293813 93 *
TickTock 0:89846a293813 94 * Data Response Token
TickTock 0:89846a293813 95 * -------------------
TickTock 0:89846a293813 96 * Every data block written to the card is acknowledged by a byte
TickTock 0:89846a293813 97 * response token
TickTock 0:89846a293813 98 *
TickTock 0:89846a293813 99 * +----------------------+
TickTock 0:89846a293813 100 * | xxx | 0 | status | 1 |
TickTock 0:89846a293813 101 * +----------------------+
TickTock 0:89846a293813 102 * 010 - OK!
TickTock 0:89846a293813 103 * 101 - CRC Error
TickTock 0:89846a293813 104 * 110 - Write Error
TickTock 0:89846a293813 105 *
TickTock 0:89846a293813 106 * Single Block Read and Write
TickTock 0:89846a293813 107 * ---------------------------
TickTock 0:89846a293813 108 *
TickTock 0:89846a293813 109 * Block transfers have a byte header, followed by the data, followed
TickTock 0:89846a293813 110 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
TickTock 0:89846a293813 111 *
TickTock 0:89846a293813 112 * +------+---------+---------+- - - -+---------+-----------+----------+
TickTock 0:89846a293813 113 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
TickTock 0:89846a293813 114 * +------+---------+---------+- - - -+---------+-----------+----------+
TickTock 0:89846a293813 115 */
TickTock 0:89846a293813 116
TickTock 0:89846a293813 117 /*
TickTock 0:89846a293813 118 * Comment: Changes for SDHC support till 32GB
TickTock 0:89846a293813 119 * Name: KB
TickTock 0:89846a293813 120 * Date: 07/24/2010
TickTock 0:89846a293813 121 * Release: 0.1
TickTock 0:89846a293813 122 */
TickTock 0:89846a293813 123
TickTock 0:89846a293813 124 #include "SDHCFileSystem.h"
TickTock 0:89846a293813 125
TickTock 0:89846a293813 126 #define DEBUG
TickTock 0:89846a293813 127 #define SD_COMMAND_TIMEOUT 5000
TickTock 0:89846a293813 128
TickTock 0:89846a293813 129
TickTock 0:89846a293813 130 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
TickTock 0:89846a293813 131 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
TickTock 0:89846a293813 132 _cs = 1;
TickTock 0:89846a293813 133 }
TickTock 0:89846a293813 134
TickTock 0:89846a293813 135 #define R1_IDLE_STATE (1 << 0)
TickTock 0:89846a293813 136 #define R1_ERASE_RESET (1 << 1)
TickTock 0:89846a293813 137 #define R1_ILLEGAL_COMMAND (1 << 2)
TickTock 0:89846a293813 138 #define R1_COM_CRC_ERROR (1 << 3)
TickTock 0:89846a293813 139 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
TickTock 0:89846a293813 140 #define R1_ADDRESS_ERROR (1 << 5)
TickTock 0:89846a293813 141 #define R1_PARAMETER_ERROR (1 << 6)
TickTock 0:89846a293813 142
TickTock 0:89846a293813 143 // Types
TickTock 0:89846a293813 144 // - v1.x Standard Capacity
TickTock 0:89846a293813 145 // - v2.x Standard Capacity
TickTock 0:89846a293813 146 // - v2.x High Capacity
TickTock 0:89846a293813 147 // - Not recognised as an SD Card
TickTock 0:89846a293813 148
TickTock 0:89846a293813 149 #define SDCARD_FAIL 0
TickTock 0:89846a293813 150 #define SDCARD_V1 1
TickTock 0:89846a293813 151 #define SDCARD_V2 2
TickTock 0:89846a293813 152 #define SDCARD_V2HC 3
TickTock 0:89846a293813 153
TickTock 0:89846a293813 154 int SDFileSystem::initialise_card() {
TickTock 0:89846a293813 155 // Set to 100kHz for initialisation, and clock card with cs = 1
TickTock 0:89846a293813 156 _spi.frequency(100000);
TickTock 0:89846a293813 157 _cs = 1;
TickTock 0:89846a293813 158 for(int i=0; i<16; i++) {
TickTock 0:89846a293813 159 _spi.write(0xFF);
TickTock 0:89846a293813 160 }
TickTock 0:89846a293813 161
TickTock 0:89846a293813 162 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
TickTock 0:89846a293813 163 if(_cmd(0, 0) != R1_IDLE_STATE) {
TickTock 0:89846a293813 164 fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
TickTock 0:89846a293813 165 return SDCARD_FAIL;
TickTock 0:89846a293813 166 }
TickTock 0:89846a293813 167
TickTock 0:89846a293813 168 // send CMD8 to determine whther it is ver 2.x
TickTock 0:89846a293813 169 int r = _cmd8();
TickTock 0:89846a293813 170 if(r == R1_IDLE_STATE) {
TickTock 0:89846a293813 171 return initialise_card_v2();
TickTock 0:89846a293813 172 } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
TickTock 0:89846a293813 173 return initialise_card_v1();
TickTock 0:89846a293813 174 } else {
TickTock 0:89846a293813 175 fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
TickTock 0:89846a293813 176 return SDCARD_FAIL;
TickTock 0:89846a293813 177 }
TickTock 0:89846a293813 178 }
TickTock 0:89846a293813 179
TickTock 0:89846a293813 180 int SDFileSystem::initialise_card_v1() {
TickTock 0:89846a293813 181 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
TickTock 0:89846a293813 182 _cmd(55, 0);
TickTock 0:89846a293813 183 if(_cmd(41, 0) == 0) {
TickTock 0:89846a293813 184 cdv = 512;
TickTock 0:89846a293813 185 #ifdef DEBUG
TickTock 0:89846a293813 186 printf("\n\rInit: SEDCARD_V1\n\r");
TickTock 0:89846a293813 187 #endif
TickTock 0:89846a293813 188 return SDCARD_V1;
TickTock 0:89846a293813 189 }
TickTock 0:89846a293813 190 }
TickTock 0:89846a293813 191
TickTock 0:89846a293813 192 fprintf(stderr, "Timeout waiting for v1.x card\n");
TickTock 0:89846a293813 193 return SDCARD_FAIL;
TickTock 0:89846a293813 194 }
TickTock 0:89846a293813 195
TickTock 0:89846a293813 196 int SDFileSystem::initialise_card_v2() {
TickTock 0:89846a293813 197
TickTock 0:89846a293813 198 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
TickTock 0:89846a293813 199 wait_ms(50);
TickTock 0:89846a293813 200 _cmd58();
TickTock 0:89846a293813 201 _cmd(55, 0);
TickTock 0:89846a293813 202 if(_cmd(41, 0x40000000) == 0) {
TickTock 0:89846a293813 203 _cmd58();
TickTock 0:89846a293813 204 #ifdef DEBUG
TickTock 0:89846a293813 205 printf("\n\rInit: SDCARD_V2\n\r");
TickTock 0:89846a293813 206 #endif
TickTock 0:89846a293813 207 cdv = 1;
TickTock 0:89846a293813 208 return SDCARD_V2;
TickTock 0:89846a293813 209 }
TickTock 0:89846a293813 210 }
TickTock 0:89846a293813 211
TickTock 0:89846a293813 212 fprintf(stderr, "Timeout waiting for v2.x card\n");
TickTock 0:89846a293813 213 return SDCARD_FAIL;
TickTock 0:89846a293813 214 }
TickTock 0:89846a293813 215
TickTock 0:89846a293813 216 int SDFileSystem::disk_initialize() {
TickTock 0:89846a293813 217
TickTock 0:89846a293813 218 int i = initialise_card();
TickTock 0:89846a293813 219 #ifdef DEBUG
TickTock 0:89846a293813 220 printf("init card = %d\n", i);
TickTock 0:89846a293813 221 #endif
TickTock 0:89846a293813 222 _sectors = _sd_sectors();
TickTock 0:89846a293813 223
TickTock 0:89846a293813 224 // Set block length to 512 (CMD16)
TickTock 0:89846a293813 225 if(_cmd(16, 512) != 0) {
TickTock 0:89846a293813 226 fprintf(stderr, "Set 512-byte block timed out\n");
TickTock 0:89846a293813 227 return 1;
TickTock 0:89846a293813 228 }
TickTock 0:89846a293813 229
TickTock 0:89846a293813 230 _spi.frequency(10000000); // Set to 10MHz for data transfer
TickTock 0:89846a293813 231 return 0;
TickTock 0:89846a293813 232 }
TickTock 0:89846a293813 233
TickTock 0:89846a293813 234 int SDFileSystem::disk_write(const char *buffer, int block_number) {
TickTock 0:89846a293813 235 // set write address for single block (CMD24)
TickTock 0:89846a293813 236 if(_cmd(24, block_number * cdv) != 0) {
TickTock 0:89846a293813 237 return 1;
TickTock 0:89846a293813 238 }
TickTock 0:89846a293813 239
TickTock 0:89846a293813 240 // send the data block
TickTock 0:89846a293813 241 _write(buffer, 512);
TickTock 0:89846a293813 242 return 0;
TickTock 0:89846a293813 243 }
TickTock 0:89846a293813 244
TickTock 0:89846a293813 245 int SDFileSystem::disk_read(char *buffer, int block_number) {
TickTock 0:89846a293813 246 // set read address for single block (CMD17)
TickTock 0:89846a293813 247 if(_cmd(17, block_number * cdv) != 0) {
TickTock 0:89846a293813 248 return 1;
TickTock 0:89846a293813 249 }
TickTock 0:89846a293813 250
TickTock 0:89846a293813 251 // receive the data
TickTock 0:89846a293813 252 _read(buffer, 512);
TickTock 0:89846a293813 253 return 0;
TickTock 0:89846a293813 254 }
TickTock 0:89846a293813 255
TickTock 0:89846a293813 256 int SDFileSystem::disk_status() { return 0; }
TickTock 0:89846a293813 257 int SDFileSystem::disk_sync() { return 0; }
TickTock 0:89846a293813 258 int SDFileSystem::disk_sectors() { return _sectors; }
TickTock 0:89846a293813 259
TickTock 0:89846a293813 260 // PRIVATE FUNCTIONS
TickTock 0:89846a293813 261
TickTock 0:89846a293813 262 int SDFileSystem::_cmd(int cmd, int arg) {
TickTock 0:89846a293813 263 _cs = 0;
TickTock 0:89846a293813 264
TickTock 0:89846a293813 265 // send a command
TickTock 0:89846a293813 266 _spi.write(0x40 | cmd);
TickTock 0:89846a293813 267 _spi.write(arg >> 24);
TickTock 0:89846a293813 268 _spi.write(arg >> 16);
TickTock 0:89846a293813 269 _spi.write(arg >> 8);
TickTock 0:89846a293813 270 _spi.write(arg >> 0);
TickTock 0:89846a293813 271 _spi.write(0x95);
TickTock 0:89846a293813 272
TickTock 0:89846a293813 273 // wait for the repsonse (response[7] == 0)
TickTock 0:89846a293813 274 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
TickTock 0:89846a293813 275 int response = _spi.write(0xFF);
TickTock 0:89846a293813 276 if(!(response & 0x80)) {
TickTock 0:89846a293813 277 _cs = 1;
TickTock 0:89846a293813 278 _spi.write(0xFF);
TickTock 0:89846a293813 279 return response;
TickTock 0:89846a293813 280 }
TickTock 0:89846a293813 281 }
TickTock 0:89846a293813 282 _cs = 1;
TickTock 0:89846a293813 283 _spi.write(0xFF);
TickTock 0:89846a293813 284 return -1; // timeout
TickTock 0:89846a293813 285 }
TickTock 0:89846a293813 286 int SDFileSystem::_cmdx(int cmd, int arg) {
TickTock 0:89846a293813 287 _cs = 0;
TickTock 0:89846a293813 288
TickTock 0:89846a293813 289 // send a command
TickTock 0:89846a293813 290 _spi.write(0x40 | cmd);
TickTock 0:89846a293813 291 _spi.write(arg >> 24);
TickTock 0:89846a293813 292 _spi.write(arg >> 16);
TickTock 0:89846a293813 293 _spi.write(arg >> 8);
TickTock 0:89846a293813 294 _spi.write(arg >> 0);
TickTock 0:89846a293813 295 _spi.write(0x95);
TickTock 0:89846a293813 296
TickTock 0:89846a293813 297 // wait for the repsonse (response[7] == 0)
TickTock 0:89846a293813 298 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
TickTock 0:89846a293813 299 int response = _spi.write(0xFF);
TickTock 0:89846a293813 300 if(!(response & 0x80)) {
TickTock 0:89846a293813 301 return response;
TickTock 0:89846a293813 302 }
TickTock 0:89846a293813 303 }
TickTock 0:89846a293813 304 _cs = 1;
TickTock 0:89846a293813 305 _spi.write(0xFF);
TickTock 0:89846a293813 306 return -1; // timeout
TickTock 0:89846a293813 307 }
TickTock 0:89846a293813 308
TickTock 0:89846a293813 309
TickTock 0:89846a293813 310 int SDFileSystem::_cmd58() {
TickTock 0:89846a293813 311 _cs = 0;
TickTock 0:89846a293813 312 int arg = 0;
TickTock 0:89846a293813 313
TickTock 0:89846a293813 314 // send a command
TickTock 0:89846a293813 315 _spi.write(0x40 | 58);
TickTock 0:89846a293813 316 _spi.write(arg >> 24);
TickTock 0:89846a293813 317 _spi.write(arg >> 16);
TickTock 0:89846a293813 318 _spi.write(arg >> 8);
TickTock 0:89846a293813 319 _spi.write(arg >> 0);
TickTock 0:89846a293813 320 _spi.write(0x95);
TickTock 0:89846a293813 321
TickTock 0:89846a293813 322 // wait for the repsonse (response[7] == 0)
TickTock 0:89846a293813 323 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
TickTock 0:89846a293813 324 int response = _spi.write(0xFF);
TickTock 0:89846a293813 325 if(!(response & 0x80)) {
TickTock 0:89846a293813 326 int ocr = _spi.write(0xFF) << 24;
TickTock 0:89846a293813 327 ocr |= _spi.write(0xFF) << 16;
TickTock 0:89846a293813 328 ocr |= _spi.write(0xFF) << 8;
TickTock 0:89846a293813 329 ocr |= _spi.write(0xFF) << 0;
TickTock 0:89846a293813 330 // printf("OCR = 0x%08X\n", ocr);
TickTock 0:89846a293813 331 _cs = 1;
TickTock 0:89846a293813 332 _spi.write(0xFF);
TickTock 0:89846a293813 333 return response;
TickTock 0:89846a293813 334 }
TickTock 0:89846a293813 335 }
TickTock 0:89846a293813 336 _cs = 1;
TickTock 0:89846a293813 337 _spi.write(0xFF);
TickTock 0:89846a293813 338 return -1; // timeout
TickTock 0:89846a293813 339 }
TickTock 0:89846a293813 340
TickTock 0:89846a293813 341 int SDFileSystem::_cmd8() {
TickTock 0:89846a293813 342 _cs = 0;
TickTock 0:89846a293813 343
TickTock 0:89846a293813 344 // send a command
TickTock 0:89846a293813 345 _spi.write(0x40 | 8); // CMD8
TickTock 0:89846a293813 346 _spi.write(0x00); // reserved
TickTock 0:89846a293813 347 _spi.write(0x00); // reserved
TickTock 0:89846a293813 348 _spi.write(0x01); // 3.3v
TickTock 0:89846a293813 349 _spi.write(0xAA); // check pattern
TickTock 0:89846a293813 350 _spi.write(0x87); // crc
TickTock 0:89846a293813 351
TickTock 0:89846a293813 352 // wait for the repsonse (response[7] == 0)
TickTock 0:89846a293813 353 for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
TickTock 0:89846a293813 354 char response[5];
TickTock 0:89846a293813 355 response[0] = _spi.write(0xFF);
TickTock 0:89846a293813 356 if(!(response[0] & 0x80)) {
TickTock 0:89846a293813 357 for(int j=1; j<5; j++) {
TickTock 0:89846a293813 358 response[i] = _spi.write(0xFF);
TickTock 0:89846a293813 359 }
TickTock 0:89846a293813 360 _cs = 1;
TickTock 0:89846a293813 361 _spi.write(0xFF);
TickTock 0:89846a293813 362 return response[0];
TickTock 0:89846a293813 363 }
TickTock 0:89846a293813 364 }
TickTock 0:89846a293813 365 _cs = 1;
TickTock 0:89846a293813 366 _spi.write(0xFF);
TickTock 0:89846a293813 367 return -1; // timeout
TickTock 0:89846a293813 368 }
TickTock 0:89846a293813 369
TickTock 0:89846a293813 370 int SDFileSystem::_read(char *buffer, int length) {
TickTock 0:89846a293813 371 _cs = 0;
TickTock 0:89846a293813 372
TickTock 0:89846a293813 373 // read until start byte (0xFF)
TickTock 0:89846a293813 374 while(_spi.write(0xFF) != 0xFE);
TickTock 0:89846a293813 375
TickTock 0:89846a293813 376 // read data
TickTock 0:89846a293813 377 for(int i=0; i<length; i++) {
TickTock 0:89846a293813 378 buffer[i] = _spi.write(0xFF);
TickTock 0:89846a293813 379 }
TickTock 0:89846a293813 380 _spi.write(0xFF); // checksum
TickTock 0:89846a293813 381 _spi.write(0xFF);
TickTock 0:89846a293813 382
TickTock 0:89846a293813 383 _cs = 1;
TickTock 0:89846a293813 384 _spi.write(0xFF);
TickTock 0:89846a293813 385 return 0;
TickTock 0:89846a293813 386 }
TickTock 0:89846a293813 387
TickTock 0:89846a293813 388 int SDFileSystem::_write(const char *buffer, int length) {
TickTock 0:89846a293813 389 _cs = 0;
TickTock 0:89846a293813 390
TickTock 0:89846a293813 391 // indicate start of block
TickTock 0:89846a293813 392 _spi.write(0xFE);
TickTock 0:89846a293813 393
TickTock 0:89846a293813 394 // write the data
TickTock 0:89846a293813 395 for(int i=0; i<length; i++) {
TickTock 0:89846a293813 396 _spi.write(buffer[i]);
TickTock 0:89846a293813 397 }
TickTock 0:89846a293813 398
TickTock 0:89846a293813 399 // write the checksum
TickTock 0:89846a293813 400 _spi.write(0xFF);
TickTock 0:89846a293813 401 _spi.write(0xFF);
TickTock 0:89846a293813 402
TickTock 0:89846a293813 403 // check the repsonse token
TickTock 0:89846a293813 404 if((_spi.write(0xFF) & 0x1F) != 0x05) {
TickTock 0:89846a293813 405 _cs = 1;
TickTock 0:89846a293813 406 _spi.write(0xFF);
TickTock 0:89846a293813 407 return 1;
TickTock 0:89846a293813 408 }
TickTock 0:89846a293813 409
TickTock 0:89846a293813 410 // wait for write to finish
TickTock 0:89846a293813 411 while(_spi.write(0xFF) == 0);
TickTock 0:89846a293813 412
TickTock 0:89846a293813 413 _cs = 1;
TickTock 0:89846a293813 414 _spi.write(0xFF);
TickTock 0:89846a293813 415 return 0;
TickTock 0:89846a293813 416 }
TickTock 0:89846a293813 417
TickTock 0:89846a293813 418 static int ext_bits(char *data, int msb, int lsb) {
TickTock 0:89846a293813 419 int bits = 0;
TickTock 0:89846a293813 420 int size = 1 + msb - lsb;
TickTock 0:89846a293813 421 for(int i=0; i<size; i++) {
TickTock 0:89846a293813 422 int position = lsb + i;
TickTock 0:89846a293813 423 int byte = 15 - (position >> 3);
TickTock 0:89846a293813 424 int bit = position & 0x7;
TickTock 0:89846a293813 425 int value = (data[byte] >> bit) & 1;
TickTock 0:89846a293813 426 bits |= value << i;
TickTock 0:89846a293813 427 }
TickTock 0:89846a293813 428 return bits;
TickTock 0:89846a293813 429 }
TickTock 0:89846a293813 430
TickTock 0:89846a293813 431 int SDFileSystem::_sd_sectors() {
TickTock 0:89846a293813 432
TickTock 0:89846a293813 433 int c_size, c_size_mult, read_bl_len;
TickTock 0:89846a293813 434 int block_len, mult, blocknr, capacity;
TickTock 0:89846a293813 435 int blocks, hc_c_size;
TickTock 0:89846a293813 436 uint64_t hc_capacity;
TickTock 0:89846a293813 437
TickTock 0:89846a293813 438 // CMD9, Response R2 (R1 byte + 16-byte block read)
TickTock 0:89846a293813 439 if(_cmdx(9, 0) != 0) {
TickTock 0:89846a293813 440 fprintf(stderr, "Didn't get a response from the disk\n");
TickTock 0:89846a293813 441 return 0;
TickTock 0:89846a293813 442 }
TickTock 0:89846a293813 443
TickTock 0:89846a293813 444 char csd[16];
TickTock 0:89846a293813 445 if(_read(csd, 16) != 0) {
TickTock 0:89846a293813 446 fprintf(stderr, "Couldn't read csd response from disk\n");
TickTock 0:89846a293813 447 return 0;
TickTock 0:89846a293813 448 }
TickTock 0:89846a293813 449
TickTock 0:89846a293813 450 // csd_structure : csd[127:126]
TickTock 0:89846a293813 451 // c_size : csd[73:62]
TickTock 0:89846a293813 452 // c_size_mult : csd[49:47]
TickTock 0:89846a293813 453 // read_bl_len : csd[83:80] - the *maximum* read block length
TickTock 0:89846a293813 454
TickTock 0:89846a293813 455 int csd_structure = ext_bits(csd, 127, 126);
TickTock 0:89846a293813 456
TickTock 0:89846a293813 457 #ifdef DEBUG
TickTock 0:89846a293813 458 printf("\n\rCSD_STRUCT = %d\n", csd_structure);
TickTock 0:89846a293813 459 #endif
TickTock 0:89846a293813 460
TickTock 0:89846a293813 461 switch (csd_structure){
TickTock 0:89846a293813 462 case 0:
TickTock 0:89846a293813 463 {
TickTock 0:89846a293813 464 cdv = 512;
TickTock 0:89846a293813 465 c_size = ext_bits(csd, 73, 62);
TickTock 0:89846a293813 466 c_size_mult = ext_bits(csd, 49, 47);
TickTock 0:89846a293813 467 read_bl_len = ext_bits(csd, 83, 80);
TickTock 0:89846a293813 468
TickTock 0:89846a293813 469 block_len = 1 << read_bl_len;
TickTock 0:89846a293813 470 mult = 1 << (c_size_mult + 2);
TickTock 0:89846a293813 471 blocknr = (c_size + 1) * mult;
TickTock 0:89846a293813 472 capacity = blocknr * block_len;
TickTock 0:89846a293813 473 blocks = capacity / 512;
TickTock 0:89846a293813 474 #ifdef DEBUG
TickTock 0:89846a293813 475 printf("\n\rSDCard\n\rc_size: %.4X \n\rcapacity: %.ld \n\rsectors: %d\n\r", c_size, capacity, blocks);
TickTock 0:89846a293813 476 #endif
TickTock 0:89846a293813 477 break;
TickTock 0:89846a293813 478 }
TickTock 0:89846a293813 479 case 1:
TickTock 0:89846a293813 480 {
TickTock 0:89846a293813 481 cdv = 1;
TickTock 0:89846a293813 482 hc_c_size = ext_bits(csd, 63, 48);
TickTock 0:89846a293813 483 int hc_read_bl_len = ext_bits(csd, 83, 80);
TickTock 0:89846a293813 484 hc_capacity = hc_c_size+1;
TickTock 0:89846a293813 485 blocks = (hc_c_size+1)*1024;
TickTock 0:89846a293813 486 #ifdef DEBUG
TickTock 0:89846a293813 487 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);
TickTock 0:89846a293813 488 #endif
TickTock 0:89846a293813 489 break;
TickTock 0:89846a293813 490 }
TickTock 0:89846a293813 491 default:
TickTock 0:89846a293813 492 fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
TickTock 0:89846a293813 493 return 0;
TickTock 0:89846a293813 494 //break;
TickTock 0:89846a293813 495 };
TickTock 0:89846a293813 496 return blocks;
TickTock 0:89846a293813 497 }