My Billy Bass program, see my notebook for details

Dependencies:   EthernetNetIf mbed

Committer:
tombracer
Date:
Sat Aug 14 19:00:53 2010 +0000
Revision:
0:7613b886e052

        

Who changed what in which revision?

UserRevisionLine numberNew contents of line
tombracer 0:7613b886e052 1 /* mbed SDFileSystem Library, for providing file access to SD cards
tombracer 0:7613b886e052 2 * Copyright (c) 2008-2010, sford
tombracer 0:7613b886e052 3 *
tombracer 0:7613b886e052 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
tombracer 0:7613b886e052 5 * of this software and associated documentation files (the "Software"), to deal
tombracer 0:7613b886e052 6 * in the Software without restriction, including without limitation the rights
tombracer 0:7613b886e052 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
tombracer 0:7613b886e052 8 * copies of the Software, and to permit persons to whom the Software is
tombracer 0:7613b886e052 9 * furnished to do so, subject to the following conditions:
tombracer 0:7613b886e052 10 *
tombracer 0:7613b886e052 11 * The above copyright notice and this permission notice shall be included in
tombracer 0:7613b886e052 12 * all copies or substantial portions of the Software.
tombracer 0:7613b886e052 13 *
tombracer 0:7613b886e052 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
tombracer 0:7613b886e052 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
tombracer 0:7613b886e052 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
tombracer 0:7613b886e052 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
tombracer 0:7613b886e052 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
tombracer 0:7613b886e052 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
tombracer 0:7613b886e052 20 * THE SOFTWARE.
tombracer 0:7613b886e052 21 */
tombracer 0:7613b886e052 22
tombracer 0:7613b886e052 23 /* Introduction
tombracer 0:7613b886e052 24 * ------------
tombracer 0:7613b886e052 25 * SD and MMC cards support a number of interfaces, but common to them all
tombracer 0:7613b886e052 26 * is one based on SPI. This is the one I'm implmenting because it means
tombracer 0:7613b886e052 27 * it is much more portable even though not so performant, and we already
tombracer 0:7613b886e052 28 * have the mbed SPI Interface!
tombracer 0:7613b886e052 29 *
tombracer 0:7613b886e052 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
tombracer 0:7613b886e052 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
tombracer 0:7613b886e052 32 *
tombracer 0:7613b886e052 33 * SPI Startup
tombracer 0:7613b886e052 34 * -----------
tombracer 0:7613b886e052 35 * The SD card powers up in SD mode. The SPI interface mode is selected by
tombracer 0:7613b886e052 36 * asserting CS low and sending the reset command (CMD0). The card will
tombracer 0:7613b886e052 37 * respond with a (R1) response.
tombracer 0:7613b886e052 38 *
tombracer 0:7613b886e052 39 * CMD8 is optionally sent to determine the voltage range supported, and
tombracer 0:7613b886e052 40 * indirectly determine whether it is a version 1.x SD/non-SD card or
tombracer 0:7613b886e052 41 * version 2.x. I'll just ignore this for now.
tombracer 0:7613b886e052 42 *
tombracer 0:7613b886e052 43 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
tombracer 0:7613b886e052 44 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
tombracer 0:7613b886e052 45 *
tombracer 0:7613b886e052 46 * You should also indicate whether the host supports High Capicity cards,
tombracer 0:7613b886e052 47 * and check whether the card is high capacity - i'll also ignore this
tombracer 0:7613b886e052 48 *
tombracer 0:7613b886e052 49 * SPI Protocol
tombracer 0:7613b886e052 50 * ------------
tombracer 0:7613b886e052 51 * The SD SPI protocol is based on transactions made up of 8-bit words, with
tombracer 0:7613b886e052 52 * the host starting every bus transaction by asserting the CS signal low. The
tombracer 0:7613b886e052 53 * card always responds to commands, data blocks and errors.
tombracer 0:7613b886e052 54 *
tombracer 0:7613b886e052 55 * The protocol supports a CRC, but by default it is off (except for the
tombracer 0:7613b886e052 56 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
tombracer 0:7613b886e052 57 * I'll leave the CRC off I think!
tombracer 0:7613b886e052 58 *
tombracer 0:7613b886e052 59 * Standard capacity cards have variable data block sizes, whereas High
tombracer 0:7613b886e052 60 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
tombracer 0:7613b886e052 61 * just always use the Standard Capacity cards with a block size of 512 bytes.
tombracer 0:7613b886e052 62 * This is set with CMD16.
tombracer 0:7613b886e052 63 *
tombracer 0:7613b886e052 64 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
tombracer 0:7613b886e052 65 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
tombracer 0:7613b886e052 66 * the card gets a read command, it responds with a response token, and then
tombracer 0:7613b886e052 67 * a data token or an error.
tombracer 0:7613b886e052 68 *
tombracer 0:7613b886e052 69 * SPI Command Format
tombracer 0:7613b886e052 70 * ------------------
tombracer 0:7613b886e052 71 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
tombracer 0:7613b886e052 72 *
tombracer 0:7613b886e052 73 * +---------------+------------+------------+-----------+----------+--------------+
tombracer 0:7613b886e052 74 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
tombracer 0:7613b886e052 75 * +---------------+------------+------------+-----------+----------+--------------+
tombracer 0:7613b886e052 76 *
tombracer 0:7613b886e052 77 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
tombracer 0:7613b886e052 78 *
tombracer 0:7613b886e052 79 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
tombracer 0:7613b886e052 80 *
tombracer 0:7613b886e052 81 * SPI Response Format
tombracer 0:7613b886e052 82 * -------------------
tombracer 0:7613b886e052 83 * The main response format (R1) is a status byte (normally zero). Key flags:
tombracer 0:7613b886e052 84 * idle - 1 if the card is in an idle state/initialising
tombracer 0:7613b886e052 85 * cmd - 1 if an illegal command code was detected
tombracer 0:7613b886e052 86 *
tombracer 0:7613b886e052 87 * +-------------------------------------------------+
tombracer 0:7613b886e052 88 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
tombracer 0:7613b886e052 89 * +-------------------------------------------------+
tombracer 0:7613b886e052 90 *
tombracer 0:7613b886e052 91 * R1b is the same, except it is followed by a busy signal (zeros) until
tombracer 0:7613b886e052 92 * the first non-zero byte when it is ready again.
tombracer 0:7613b886e052 93 *
tombracer 0:7613b886e052 94 * Data Response Token
tombracer 0:7613b886e052 95 * -------------------
tombracer 0:7613b886e052 96 * Every data block written to the card is acknowledged by a byte
tombracer 0:7613b886e052 97 * response token
tombracer 0:7613b886e052 98 *
tombracer 0:7613b886e052 99 * +----------------------+
tombracer 0:7613b886e052 100 * | xxx | 0 | status | 1 |
tombracer 0:7613b886e052 101 * +----------------------+
tombracer 0:7613b886e052 102 * 010 - OK!
tombracer 0:7613b886e052 103 * 101 - CRC Error
tombracer 0:7613b886e052 104 * 110 - Write Error
tombracer 0:7613b886e052 105 *
tombracer 0:7613b886e052 106 * Single Block Read and Write
tombracer 0:7613b886e052 107 * ---------------------------
tombracer 0:7613b886e052 108 *
tombracer 0:7613b886e052 109 * Block transfers have a byte header, followed by the data, followed
tombracer 0:7613b886e052 110 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
tombracer 0:7613b886e052 111 *
tombracer 0:7613b886e052 112 * +------+---------+---------+- - - -+---------+-----------+----------+
tombracer 0:7613b886e052 113 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
tombracer 0:7613b886e052 114 * +------+---------+---------+- - - -+---------+-----------+----------+
tombracer 0:7613b886e052 115 */
tombracer 0:7613b886e052 116
tombracer 0:7613b886e052 117 /*
tombracer 0:7613b886e052 118 * Comment: Changes for SDHC support till 32GB
tombracer 0:7613b886e052 119 * Name: KB
tombracer 0:7613b886e052 120 * Date: 07/24/2010
tombracer 0:7613b886e052 121 * Release: 0.1
tombracer 0:7613b886e052 122 */
tombracer 0:7613b886e052 123
tombracer 0:7613b886e052 124 #include "SDHCFileSystem.h"
tombracer 0:7613b886e052 125
tombracer 0:7613b886e052 126 #define DEBUG
tombracer 0:7613b886e052 127 #define SD_COMMAND_TIMEOUT 5000
tombracer 0:7613b886e052 128
tombracer 0:7613b886e052 129
tombracer 0:7613b886e052 130 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
tombracer 0:7613b886e052 131 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
tombracer 0:7613b886e052 132 _cs = 1;
tombracer 0:7613b886e052 133 }
tombracer 0:7613b886e052 134
tombracer 0:7613b886e052 135 #define R1_IDLE_STATE (1 << 0)
tombracer 0:7613b886e052 136 #define R1_ERASE_RESET (1 << 1)
tombracer 0:7613b886e052 137 #define R1_ILLEGAL_COMMAND (1 << 2)
tombracer 0:7613b886e052 138 #define R1_COM_CRC_ERROR (1 << 3)
tombracer 0:7613b886e052 139 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
tombracer 0:7613b886e052 140 #define R1_ADDRESS_ERROR (1 << 5)
tombracer 0:7613b886e052 141 #define R1_PARAMETER_ERROR (1 << 6)
tombracer 0:7613b886e052 142
tombracer 0:7613b886e052 143 // Types
tombracer 0:7613b886e052 144 // - v1.x Standard Capacity
tombracer 0:7613b886e052 145 // - v2.x Standard Capacity
tombracer 0:7613b886e052 146 // - v2.x High Capacity
tombracer 0:7613b886e052 147 // - Not recognised as an SD Card
tombracer 0:7613b886e052 148
tombracer 0:7613b886e052 149 #define SDCARD_FAIL 0
tombracer 0:7613b886e052 150 #define SDCARD_V1 1
tombracer 0:7613b886e052 151 #define SDCARD_V2 2
tombracer 0:7613b886e052 152 #define SDCARD_V2HC 3
tombracer 0:7613b886e052 153
tombracer 0:7613b886e052 154 int SDFileSystem::initialise_card() {
tombracer 0:7613b886e052 155 // Set to 100kHz for initialisation, and clock card with cs = 1
tombracer 0:7613b886e052 156 _spi.frequency(100000);
tombracer 0:7613b886e052 157 _cs = 1;
tombracer 0:7613b886e052 158 for(int i=0; i<16; i++) {
tombracer 0:7613b886e052 159 _spi.write(0xFF);
tombracer 0:7613b886e052 160 }
tombracer 0:7613b886e052 161
tombracer 0:7613b886e052 162 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
tombracer 0:7613b886e052 163 if(_cmd(0, 0) != R1_IDLE_STATE) {
tombracer 0:7613b886e052 164 fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
tombracer 0:7613b886e052 165 return SDCARD_FAIL;
tombracer 0:7613b886e052 166 }
tombracer 0:7613b886e052 167
tombracer 0:7613b886e052 168 // send CMD8 to determine whther it is ver 2.x
tombracer 0:7613b886e052 169 int r = _cmd8();
tombracer 0:7613b886e052 170 if(r == R1_IDLE_STATE) {
tombracer 0:7613b886e052 171 return initialise_card_v2();
tombracer 0:7613b886e052 172 } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
tombracer 0:7613b886e052 173 return initialise_card_v1();
tombracer 0:7613b886e052 174 } else {
tombracer 0:7613b886e052 175 fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
tombracer 0:7613b886e052 176 return SDCARD_FAIL;
tombracer 0:7613b886e052 177 }
tombracer 0:7613b886e052 178 }
tombracer 0:7613b886e052 179
tombracer 0:7613b886e052 180 int SDFileSystem::initialise_card_v1() {
tombracer 0:7613b886e052 181 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tombracer 0:7613b886e052 182 _cmd(55, 0);
tombracer 0:7613b886e052 183 if(_cmd(41, 0) == 0) {
tombracer 0:7613b886e052 184 cdv = 512;
tombracer 0:7613b886e052 185 #ifdef DEBUG
tombracer 0:7613b886e052 186 printf("\n\rInit: SEDCARD_V1\n\r");
tombracer 0:7613b886e052 187 #endif
tombracer 0:7613b886e052 188 return SDCARD_V1;
tombracer 0:7613b886e052 189 }
tombracer 0:7613b886e052 190 }
tombracer 0:7613b886e052 191
tombracer 0:7613b886e052 192 fprintf(stderr, "Timeout waiting for v1.x card\n");
tombracer 0:7613b886e052 193 return SDCARD_FAIL;
tombracer 0:7613b886e052 194 }
tombracer 0:7613b886e052 195
tombracer 0:7613b886e052 196 int SDFileSystem::initialise_card_v2() {
tombracer 0:7613b886e052 197
tombracer 0:7613b886e052 198 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tombracer 0:7613b886e052 199 wait_ms(50);
tombracer 0:7613b886e052 200 _cmd58();
tombracer 0:7613b886e052 201 _cmd(55, 0);
tombracer 0:7613b886e052 202 if(_cmd(41, 0x40000000) == 0) {
tombracer 0:7613b886e052 203 _cmd58();
tombracer 0:7613b886e052 204 #ifdef DEBUG
tombracer 0:7613b886e052 205 printf("\n\rInit: SDCARD_V2\n\r");
tombracer 0:7613b886e052 206 #endif
tombracer 0:7613b886e052 207 cdv = 1;
tombracer 0:7613b886e052 208 return SDCARD_V2;
tombracer 0:7613b886e052 209 }
tombracer 0:7613b886e052 210 }
tombracer 0:7613b886e052 211
tombracer 0:7613b886e052 212 fprintf(stderr, "Timeout waiting for v2.x card\n");
tombracer 0:7613b886e052 213 return SDCARD_FAIL;
tombracer 0:7613b886e052 214 }
tombracer 0:7613b886e052 215
tombracer 0:7613b886e052 216 int SDFileSystem::disk_initialize() {
tombracer 0:7613b886e052 217
tombracer 0:7613b886e052 218 int i = initialise_card();
tombracer 0:7613b886e052 219 #ifdef DEBUG
tombracer 0:7613b886e052 220 printf("init card = %d\n", i);
tombracer 0:7613b886e052 221 #endif
tombracer 0:7613b886e052 222 _sectors = _sd_sectors();
tombracer 0:7613b886e052 223
tombracer 0:7613b886e052 224 // Set block length to 512 (CMD16)
tombracer 0:7613b886e052 225 if(_cmd(16, 512) != 0) {
tombracer 0:7613b886e052 226 fprintf(stderr, "Set 512-byte block timed out\n");
tombracer 0:7613b886e052 227 return 1;
tombracer 0:7613b886e052 228 }
tombracer 0:7613b886e052 229
tombracer 0:7613b886e052 230 _spi.frequency(1000000); // Set to 1MHz for data transfer
tombracer 0:7613b886e052 231 return 0;
tombracer 0:7613b886e052 232 }
tombracer 0:7613b886e052 233
tombracer 0:7613b886e052 234 int SDFileSystem::disk_write(const char *buffer, int block_number) {
tombracer 0:7613b886e052 235 // set write address for single block (CMD24)
tombracer 0:7613b886e052 236 if(_cmd(24, block_number * cdv) != 0) {
tombracer 0:7613b886e052 237 return 1;
tombracer 0:7613b886e052 238 }
tombracer 0:7613b886e052 239
tombracer 0:7613b886e052 240 // send the data block
tombracer 0:7613b886e052 241 _write(buffer, 512);
tombracer 0:7613b886e052 242 return 0;
tombracer 0:7613b886e052 243 }
tombracer 0:7613b886e052 244
tombracer 0:7613b886e052 245 int SDFileSystem::disk_read(char *buffer, int block_number) {
tombracer 0:7613b886e052 246 // set read address for single block (CMD17)
tombracer 0:7613b886e052 247 if(_cmd(17, block_number * cdv) != 0) {
tombracer 0:7613b886e052 248 return 1;
tombracer 0:7613b886e052 249 }
tombracer 0:7613b886e052 250
tombracer 0:7613b886e052 251 // receive the data
tombracer 0:7613b886e052 252 _read(buffer, 512);
tombracer 0:7613b886e052 253 return 0;
tombracer 0:7613b886e052 254 }
tombracer 0:7613b886e052 255
tombracer 0:7613b886e052 256 int SDFileSystem::disk_status() { return 0; }
tombracer 0:7613b886e052 257 int SDFileSystem::disk_sync() { return 0; }
tombracer 0:7613b886e052 258 int SDFileSystem::disk_sectors() { return _sectors; }
tombracer 0:7613b886e052 259
tombracer 0:7613b886e052 260 // PRIVATE FUNCTIONS
tombracer 0:7613b886e052 261
tombracer 0:7613b886e052 262 int SDFileSystem::_cmd(int cmd, int arg) {
tombracer 0:7613b886e052 263 _cs = 0;
tombracer 0:7613b886e052 264
tombracer 0:7613b886e052 265 // send a command
tombracer 0:7613b886e052 266 _spi.write(0x40 | cmd);
tombracer 0:7613b886e052 267 _spi.write(arg >> 24);
tombracer 0:7613b886e052 268 _spi.write(arg >> 16);
tombracer 0:7613b886e052 269 _spi.write(arg >> 8);
tombracer 0:7613b886e052 270 _spi.write(arg >> 0);
tombracer 0:7613b886e052 271 _spi.write(0x95);
tombracer 0:7613b886e052 272
tombracer 0:7613b886e052 273 // wait for the repsonse (response[7] == 0)
tombracer 0:7613b886e052 274 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tombracer 0:7613b886e052 275 int response = _spi.write(0xFF);
tombracer 0:7613b886e052 276 if(!(response & 0x80)) {
tombracer 0:7613b886e052 277 _cs = 1;
tombracer 0:7613b886e052 278 _spi.write(0xFF);
tombracer 0:7613b886e052 279 return response;
tombracer 0:7613b886e052 280 }
tombracer 0:7613b886e052 281 }
tombracer 0:7613b886e052 282 _cs = 1;
tombracer 0:7613b886e052 283 _spi.write(0xFF);
tombracer 0:7613b886e052 284 return -1; // timeout
tombracer 0:7613b886e052 285 }
tombracer 0:7613b886e052 286 int SDFileSystem::_cmdx(int cmd, int arg) {
tombracer 0:7613b886e052 287 _cs = 0;
tombracer 0:7613b886e052 288
tombracer 0:7613b886e052 289 // send a command
tombracer 0:7613b886e052 290 _spi.write(0x40 | cmd);
tombracer 0:7613b886e052 291 _spi.write(arg >> 24);
tombracer 0:7613b886e052 292 _spi.write(arg >> 16);
tombracer 0:7613b886e052 293 _spi.write(arg >> 8);
tombracer 0:7613b886e052 294 _spi.write(arg >> 0);
tombracer 0:7613b886e052 295 _spi.write(0x95);
tombracer 0:7613b886e052 296
tombracer 0:7613b886e052 297 // wait for the repsonse (response[7] == 0)
tombracer 0:7613b886e052 298 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tombracer 0:7613b886e052 299 int response = _spi.write(0xFF);
tombracer 0:7613b886e052 300 if(!(response & 0x80)) {
tombracer 0:7613b886e052 301 return response;
tombracer 0:7613b886e052 302 }
tombracer 0:7613b886e052 303 }
tombracer 0:7613b886e052 304 _cs = 1;
tombracer 0:7613b886e052 305 _spi.write(0xFF);
tombracer 0:7613b886e052 306 return -1; // timeout
tombracer 0:7613b886e052 307 }
tombracer 0:7613b886e052 308
tombracer 0:7613b886e052 309
tombracer 0:7613b886e052 310 int SDFileSystem::_cmd58() {
tombracer 0:7613b886e052 311 _cs = 0;
tombracer 0:7613b886e052 312 int arg = 0;
tombracer 0:7613b886e052 313
tombracer 0:7613b886e052 314 // send a command
tombracer 0:7613b886e052 315 _spi.write(0x40 | 58);
tombracer 0:7613b886e052 316 _spi.write(arg >> 24);
tombracer 0:7613b886e052 317 _spi.write(arg >> 16);
tombracer 0:7613b886e052 318 _spi.write(arg >> 8);
tombracer 0:7613b886e052 319 _spi.write(arg >> 0);
tombracer 0:7613b886e052 320 _spi.write(0x95);
tombracer 0:7613b886e052 321
tombracer 0:7613b886e052 322 // wait for the repsonse (response[7] == 0)
tombracer 0:7613b886e052 323 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tombracer 0:7613b886e052 324 int response = _spi.write(0xFF);
tombracer 0:7613b886e052 325 if(!(response & 0x80)) {
tombracer 0:7613b886e052 326 int ocr = _spi.write(0xFF) << 24;
tombracer 0:7613b886e052 327 ocr |= _spi.write(0xFF) << 16;
tombracer 0:7613b886e052 328 ocr |= _spi.write(0xFF) << 8;
tombracer 0:7613b886e052 329 ocr |= _spi.write(0xFF) << 0;
tombracer 0:7613b886e052 330 // printf("OCR = 0x%08X\n", ocr);
tombracer 0:7613b886e052 331 _cs = 1;
tombracer 0:7613b886e052 332 _spi.write(0xFF);
tombracer 0:7613b886e052 333 return response;
tombracer 0:7613b886e052 334 }
tombracer 0:7613b886e052 335 }
tombracer 0:7613b886e052 336 _cs = 1;
tombracer 0:7613b886e052 337 _spi.write(0xFF);
tombracer 0:7613b886e052 338 return -1; // timeout
tombracer 0:7613b886e052 339 }
tombracer 0:7613b886e052 340
tombracer 0:7613b886e052 341 int SDFileSystem::_cmd8() {
tombracer 0:7613b886e052 342 _cs = 0;
tombracer 0:7613b886e052 343
tombracer 0:7613b886e052 344 // send a command
tombracer 0:7613b886e052 345 _spi.write(0x40 | 8); // CMD8
tombracer 0:7613b886e052 346 _spi.write(0x00); // reserved
tombracer 0:7613b886e052 347 _spi.write(0x00); // reserved
tombracer 0:7613b886e052 348 _spi.write(0x01); // 3.3v
tombracer 0:7613b886e052 349 _spi.write(0xAA); // check pattern
tombracer 0:7613b886e052 350 _spi.write(0x87); // crc
tombracer 0:7613b886e052 351
tombracer 0:7613b886e052 352 // wait for the repsonse (response[7] == 0)
tombracer 0:7613b886e052 353 for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
tombracer 0:7613b886e052 354 char response[5];
tombracer 0:7613b886e052 355 response[0] = _spi.write(0xFF);
tombracer 0:7613b886e052 356 if(!(response[0] & 0x80)) {
tombracer 0:7613b886e052 357 for(int j=1; j<5; j++) {
tombracer 0:7613b886e052 358 response[i] = _spi.write(0xFF);
tombracer 0:7613b886e052 359 }
tombracer 0:7613b886e052 360 _cs = 1;
tombracer 0:7613b886e052 361 _spi.write(0xFF);
tombracer 0:7613b886e052 362 return response[0];
tombracer 0:7613b886e052 363 }
tombracer 0:7613b886e052 364 }
tombracer 0:7613b886e052 365 _cs = 1;
tombracer 0:7613b886e052 366 _spi.write(0xFF);
tombracer 0:7613b886e052 367 return -1; // timeout
tombracer 0:7613b886e052 368 }
tombracer 0:7613b886e052 369
tombracer 0:7613b886e052 370 int SDFileSystem::_read(char *buffer, int length) {
tombracer 0:7613b886e052 371 _cs = 0;
tombracer 0:7613b886e052 372
tombracer 0:7613b886e052 373 // read until start byte (0xFF)
tombracer 0:7613b886e052 374 while(_spi.write(0xFF) != 0xFE);
tombracer 0:7613b886e052 375
tombracer 0:7613b886e052 376 // read data
tombracer 0:7613b886e052 377 for(int i=0; i<length; i++) {
tombracer 0:7613b886e052 378 buffer[i] = _spi.write(0xFF);
tombracer 0:7613b886e052 379 }
tombracer 0:7613b886e052 380 _spi.write(0xFF); // checksum
tombracer 0:7613b886e052 381 _spi.write(0xFF);
tombracer 0:7613b886e052 382
tombracer 0:7613b886e052 383 _cs = 1;
tombracer 0:7613b886e052 384 _spi.write(0xFF);
tombracer 0:7613b886e052 385 return 0;
tombracer 0:7613b886e052 386 }
tombracer 0:7613b886e052 387
tombracer 0:7613b886e052 388 int SDFileSystem::_write(const char *buffer, int length) {
tombracer 0:7613b886e052 389 _cs = 0;
tombracer 0:7613b886e052 390
tombracer 0:7613b886e052 391 // indicate start of block
tombracer 0:7613b886e052 392 _spi.write(0xFE);
tombracer 0:7613b886e052 393
tombracer 0:7613b886e052 394 // write the data
tombracer 0:7613b886e052 395 for(int i=0; i<length; i++) {
tombracer 0:7613b886e052 396 _spi.write(buffer[i]);
tombracer 0:7613b886e052 397 }
tombracer 0:7613b886e052 398
tombracer 0:7613b886e052 399 // write the checksum
tombracer 0:7613b886e052 400 _spi.write(0xFF);
tombracer 0:7613b886e052 401 _spi.write(0xFF);
tombracer 0:7613b886e052 402
tombracer 0:7613b886e052 403 // check the repsonse token
tombracer 0:7613b886e052 404 if((_spi.write(0xFF) & 0x1F) != 0x05) {
tombracer 0:7613b886e052 405 _cs = 1;
tombracer 0:7613b886e052 406 _spi.write(0xFF);
tombracer 0:7613b886e052 407 return 1;
tombracer 0:7613b886e052 408 }
tombracer 0:7613b886e052 409
tombracer 0:7613b886e052 410 // wait for write to finish
tombracer 0:7613b886e052 411 while(_spi.write(0xFF) == 0);
tombracer 0:7613b886e052 412
tombracer 0:7613b886e052 413 _cs = 1;
tombracer 0:7613b886e052 414 _spi.write(0xFF);
tombracer 0:7613b886e052 415 return 0;
tombracer 0:7613b886e052 416 }
tombracer 0:7613b886e052 417
tombracer 0:7613b886e052 418 static int ext_bits(char *data, int msb, int lsb) {
tombracer 0:7613b886e052 419 int bits = 0;
tombracer 0:7613b886e052 420 int size = 1 + msb - lsb;
tombracer 0:7613b886e052 421 for(int i=0; i<size; i++) {
tombracer 0:7613b886e052 422 int position = lsb + i;
tombracer 0:7613b886e052 423 int byte = 15 - (position >> 3);
tombracer 0:7613b886e052 424 int bit = position & 0x7;
tombracer 0:7613b886e052 425 int value = (data[byte] >> bit) & 1;
tombracer 0:7613b886e052 426 bits |= value << i;
tombracer 0:7613b886e052 427 }
tombracer 0:7613b886e052 428 return bits;
tombracer 0:7613b886e052 429 }
tombracer 0:7613b886e052 430
tombracer 0:7613b886e052 431 int SDFileSystem::_sd_sectors() {
tombracer 0:7613b886e052 432
tombracer 0:7613b886e052 433 int c_size, c_size_mult, read_bl_len;
tombracer 0:7613b886e052 434 int block_len, mult, blocknr, capacity;
tombracer 0:7613b886e052 435 int blocks, hc_c_size;
tombracer 0:7613b886e052 436 uint64_t hc_capacity;
tombracer 0:7613b886e052 437
tombracer 0:7613b886e052 438 // CMD9, Response R2 (R1 byte + 16-byte block read)
tombracer 0:7613b886e052 439 if(_cmdx(9, 0) != 0) {
tombracer 0:7613b886e052 440 fprintf(stderr, "Didn't get a response from the disk\n");
tombracer 0:7613b886e052 441 return 0;
tombracer 0:7613b886e052 442 }
tombracer 0:7613b886e052 443
tombracer 0:7613b886e052 444 char csd[16];
tombracer 0:7613b886e052 445 if(_read(csd, 16) != 0) {
tombracer 0:7613b886e052 446 fprintf(stderr, "Couldn't read csd response from disk\n");
tombracer 0:7613b886e052 447 return 0;
tombracer 0:7613b886e052 448 }
tombracer 0:7613b886e052 449
tombracer 0:7613b886e052 450 // csd_structure : csd[127:126]
tombracer 0:7613b886e052 451 // c_size : csd[73:62]
tombracer 0:7613b886e052 452 // c_size_mult : csd[49:47]
tombracer 0:7613b886e052 453 // read_bl_len : csd[83:80] - the *maximum* read block length
tombracer 0:7613b886e052 454
tombracer 0:7613b886e052 455 int csd_structure = ext_bits(csd, 127, 126);
tombracer 0:7613b886e052 456
tombracer 0:7613b886e052 457 #ifdef DEBUG
tombracer 0:7613b886e052 458 printf("\n\rCSD_STRUCT = %d\n", csd_structure);
tombracer 0:7613b886e052 459 #endif
tombracer 0:7613b886e052 460
tombracer 0:7613b886e052 461 switch (csd_structure){
tombracer 0:7613b886e052 462 case 0:
tombracer 0:7613b886e052 463 cdv = 512;
tombracer 0:7613b886e052 464 c_size = ext_bits(csd, 73, 62);
tombracer 0:7613b886e052 465 c_size_mult = ext_bits(csd, 49, 47);
tombracer 0:7613b886e052 466 read_bl_len = ext_bits(csd, 83, 80);
tombracer 0:7613b886e052 467
tombracer 0:7613b886e052 468 block_len = 1 << read_bl_len;
tombracer 0:7613b886e052 469 mult = 1 << (c_size_mult + 2);
tombracer 0:7613b886e052 470 blocknr = (c_size + 1) * mult;
tombracer 0:7613b886e052 471 capacity = blocknr * block_len;
tombracer 0:7613b886e052 472 blocks = capacity / 512;
tombracer 0:7613b886e052 473 #ifdef DEBUG
tombracer 0:7613b886e052 474 printf("\n\rSDCard\n\rc_size: %.4X \n\rcapacity: %.ld \n\rsectors: %d\n\r", c_size, capacity, blocks);
tombracer 0:7613b886e052 475 #endif
tombracer 0:7613b886e052 476 break;
tombracer 0:7613b886e052 477
tombracer 0:7613b886e052 478 case 1:
tombracer 0:7613b886e052 479 cdv = 1;
tombracer 0:7613b886e052 480 hc_c_size = ext_bits(csd, 63, 48);
tombracer 0:7613b886e052 481 int hc_read_bl_len = ext_bits(csd, 83, 80);
tombracer 0:7613b886e052 482 hc_capacity = hc_c_size+1;
tombracer 0:7613b886e052 483 blocks = (hc_c_size+1)*1024;
tombracer 0:7613b886e052 484 #ifdef DEBUG
tombracer 0:7613b886e052 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);
tombracer 0:7613b886e052 486 #endif
tombracer 0:7613b886e052 487 break;
tombracer 0:7613b886e052 488
tombracer 0:7613b886e052 489 default:
tombracer 0:7613b886e052 490 fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
tombracer 0:7613b886e052 491 return 0;
tombracer 0:7613b886e052 492 // break;
tombracer 0:7613b886e052 493 };
tombracer 0:7613b886e052 494 return blocks;
tombracer 0:7613b886e052 495 }