Toshihisa T / Mbed 2 deprecated S1315FLogger

Skytraq S1315F-RAW-EVK Logger

Dependencies:   TextLCD mbed

SDFileSystem.cpp@2:7eb11afe02bd, 2010-12-19 (annotated)

Committer:
tosihisa
Date:
Sun Dec 19 09:11:48 2010 +0000
Revision:
2:7eb11afe02bd
Parent:
0:e0ec137da369 
Add \"SYSTEM RESTART\" at boot time.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
tosihisa 0:e0ec137da369 1 /* mbed SDFileSystem Library, for providing file access to SD cards
tosihisa 0:e0ec137da369 2 * Copyright (c) 2008-2010, sford
tosihisa 0:e0ec137da369 3 *
tosihisa 0:e0ec137da369 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
tosihisa 0:e0ec137da369 5 * of this software and associated documentation files (the "Software"), to deal
tosihisa 0:e0ec137da369 6 * in the Software without restriction, including without limitation the rights
tosihisa 0:e0ec137da369 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
tosihisa 0:e0ec137da369 8 * copies of the Software, and to permit persons to whom the Software is
tosihisa 0:e0ec137da369 9 * furnished to do so, subject to the following conditions:
tosihisa 0:e0ec137da369 10 *
tosihisa 0:e0ec137da369 11 * The above copyright notice and this permission notice shall be included in
tosihisa 0:e0ec137da369 12 * all copies or substantial portions of the Software.
tosihisa 0:e0ec137da369 13 *
tosihisa 0:e0ec137da369 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
tosihisa 0:e0ec137da369 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
tosihisa 0:e0ec137da369 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
tosihisa 0:e0ec137da369 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
tosihisa 0:e0ec137da369 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
tosihisa 0:e0ec137da369 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
tosihisa 0:e0ec137da369 20 * THE SOFTWARE.
tosihisa 0:e0ec137da369 21 */
tosihisa 0:e0ec137da369 22
tosihisa 0:e0ec137da369 23 /* Introduction
tosihisa 0:e0ec137da369 24 * ------------
tosihisa 0:e0ec137da369 25 * SD and MMC cards support a number of interfaces, but common to them all
tosihisa 0:e0ec137da369 26 * is one based on SPI. This is the one I'm implmenting because it means
tosihisa 0:e0ec137da369 27 * it is much more portable even though not so performant, and we already
tosihisa 0:e0ec137da369 28 * have the mbed SPI Interface!
tosihisa 0:e0ec137da369 29 *
tosihisa 0:e0ec137da369 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
tosihisa 0:e0ec137da369 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
tosihisa 0:e0ec137da369 32 *
tosihisa 0:e0ec137da369 33 * SPI Startup
tosihisa 0:e0ec137da369 34 * -----------
tosihisa 0:e0ec137da369 35 * The SD card powers up in SD mode. The SPI interface mode is selected by
tosihisa 0:e0ec137da369 36 * asserting CS low and sending the reset command (CMD0). The card will
tosihisa 0:e0ec137da369 37 * respond with a (R1) response.
tosihisa 0:e0ec137da369 38 *
tosihisa 0:e0ec137da369 39 * CMD8 is optionally sent to determine the voltage range supported, and
tosihisa 0:e0ec137da369 40 * indirectly determine whether it is a version 1.x SD/non-SD card or
tosihisa 0:e0ec137da369 41 * version 2.x. I'll just ignore this for now.
tosihisa 0:e0ec137da369 42 *
tosihisa 0:e0ec137da369 43 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
tosihisa 0:e0ec137da369 44 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
tosihisa 0:e0ec137da369 45 *
tosihisa 0:e0ec137da369 46 * You should also indicate whether the host supports High Capicity cards,
tosihisa 0:e0ec137da369 47 * and check whether the card is high capacity - i'll also ignore this
tosihisa 0:e0ec137da369 48 *
tosihisa 0:e0ec137da369 49 * SPI Protocol
tosihisa 0:e0ec137da369 50 * ------------
tosihisa 0:e0ec137da369 51 * The SD SPI protocol is based on transactions made up of 8-bit words, with
tosihisa 0:e0ec137da369 52 * the host starting every bus transaction by asserting the CS signal low. The
tosihisa 0:e0ec137da369 53 * card always responds to commands, data blocks and errors.
tosihisa 0:e0ec137da369 54 *
tosihisa 0:e0ec137da369 55 * The protocol supports a CRC, but by default it is off (except for the
tosihisa 0:e0ec137da369 56 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
tosihisa 0:e0ec137da369 57 * I'll leave the CRC off I think!
tosihisa 0:e0ec137da369 58 *
tosihisa 0:e0ec137da369 59 * Standard capacity cards have variable data block sizes, whereas High
tosihisa 0:e0ec137da369 60 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
tosihisa 0:e0ec137da369 61 * just always use the Standard Capacity cards with a block size of 512 bytes.
tosihisa 0:e0ec137da369 62 * This is set with CMD16.
tosihisa 0:e0ec137da369 63 *
tosihisa 0:e0ec137da369 64 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
tosihisa 0:e0ec137da369 65 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
tosihisa 0:e0ec137da369 66 * the card gets a read command, it responds with a response token, and then
tosihisa 0:e0ec137da369 67 * a data token or an error.
tosihisa 0:e0ec137da369 68 *
tosihisa 0:e0ec137da369 69 * SPI Command Format
tosihisa 0:e0ec137da369 70 * ------------------
tosihisa 0:e0ec137da369 71 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
tosihisa 0:e0ec137da369 72 *
tosihisa 0:e0ec137da369 73 * +---------------+------------+------------+-----------+----------+--------------+
tosihisa 0:e0ec137da369 74 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
tosihisa 0:e0ec137da369 75 * +---------------+------------+------------+-----------+----------+--------------+
tosihisa 0:e0ec137da369 76 *
tosihisa 0:e0ec137da369 77 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
tosihisa 0:e0ec137da369 78 *
tosihisa 0:e0ec137da369 79 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
tosihisa 0:e0ec137da369 80 *
tosihisa 0:e0ec137da369 81 * SPI Response Format
tosihisa 0:e0ec137da369 82 * -------------------
tosihisa 0:e0ec137da369 83 * The main response format (R1) is a status byte (normally zero). Key flags:
tosihisa 0:e0ec137da369 84 * idle - 1 if the card is in an idle state/initialising
tosihisa 0:e0ec137da369 85 * cmd - 1 if an illegal command code was detected
tosihisa 0:e0ec137da369 86 *
tosihisa 0:e0ec137da369 87 * +-------------------------------------------------+
tosihisa 0:e0ec137da369 88 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
tosihisa 0:e0ec137da369 89 * +-------------------------------------------------+
tosihisa 0:e0ec137da369 90 *
tosihisa 0:e0ec137da369 91 * R1b is the same, except it is followed by a busy signal (zeros) until
tosihisa 0:e0ec137da369 92 * the first non-zero byte when it is ready again.
tosihisa 0:e0ec137da369 93 *
tosihisa 0:e0ec137da369 94 * Data Response Token
tosihisa 0:e0ec137da369 95 * -------------------
tosihisa 0:e0ec137da369 96 * Every data block written to the card is acknowledged by a byte
tosihisa 0:e0ec137da369 97 * response token
tosihisa 0:e0ec137da369 98 *
tosihisa 0:e0ec137da369 99 * +----------------------+
tosihisa 0:e0ec137da369 100 * | xxx | 0 | status | 1 |
tosihisa 0:e0ec137da369 101 * +----------------------+
tosihisa 0:e0ec137da369 102 * 010 - OK!
tosihisa 0:e0ec137da369 103 * 101 - CRC Error
tosihisa 0:e0ec137da369 104 * 110 - Write Error
tosihisa 0:e0ec137da369 105 *
tosihisa 0:e0ec137da369 106 * Single Block Read and Write
tosihisa 0:e0ec137da369 107 * ---------------------------
tosihisa 0:e0ec137da369 108 *
tosihisa 0:e0ec137da369 109 * Block transfers have a byte header, followed by the data, followed
tosihisa 0:e0ec137da369 110 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
tosihisa 0:e0ec137da369 111 *
tosihisa 0:e0ec137da369 112 * +------+---------+---------+- - - -+---------+-----------+----------+
tosihisa 0:e0ec137da369 113 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
tosihisa 0:e0ec137da369 114 * +------+---------+---------+- - - -+---------+-----------+----------+
tosihisa 0:e0ec137da369 115 */
tosihisa 0:e0ec137da369 116
tosihisa 0:e0ec137da369 117 #include "SDFileSystem.h"
tosihisa 0:e0ec137da369 118
tosihisa 0:e0ec137da369 119 #define SD_COMMAND_TIMEOUT 5000
tosihisa 0:e0ec137da369 120
tosihisa 0:e0ec137da369 121 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
tosihisa 0:e0ec137da369 122 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
tosihisa 0:e0ec137da369 123 _cs = 1;
tosihisa 0:e0ec137da369 124 }
tosihisa 0:e0ec137da369 125
tosihisa 0:e0ec137da369 126 #define R1_IDLE_STATE (1 << 0)
tosihisa 0:e0ec137da369 127 #define R1_ERASE_RESET (1 << 1)
tosihisa 0:e0ec137da369 128 #define R1_ILLEGAL_COMMAND (1 << 2)
tosihisa 0:e0ec137da369 129 #define R1_COM_CRC_ERROR (1 << 3)
tosihisa 0:e0ec137da369 130 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
tosihisa 0:e0ec137da369 131 #define R1_ADDRESS_ERROR (1 << 5)
tosihisa 0:e0ec137da369 132 #define R1_PARAMETER_ERROR (1 << 6)
tosihisa 0:e0ec137da369 133
tosihisa 0:e0ec137da369 134 // Types
tosihisa 0:e0ec137da369 135 // - v1.x Standard Capacity
tosihisa 0:e0ec137da369 136 // - v2.x Standard Capacity
tosihisa 0:e0ec137da369 137 // - v2.x High Capacity
tosihisa 0:e0ec137da369 138 // - Not recognised as an SD Card
tosihisa 0:e0ec137da369 139
tosihisa 0:e0ec137da369 140 #define SDCARD_FAIL 0
tosihisa 0:e0ec137da369 141 #define SDCARD_V1 1
tosihisa 0:e0ec137da369 142 #define SDCARD_V2 2
tosihisa 0:e0ec137da369 143 #define SDCARD_V2HC 3
tosihisa 0:e0ec137da369 144
tosihisa 0:e0ec137da369 145 int SDFileSystem::initialise_card() {
tosihisa 0:e0ec137da369 146 // Set to 100kHz for initialisation, and clock card with cs = 1
tosihisa 0:e0ec137da369 147 _spi.frequency(100000);
tosihisa 0:e0ec137da369 148 _cs = 1;
tosihisa 0:e0ec137da369 149 for(int i=0; i<16; i++) {
tosihisa 0:e0ec137da369 150 _spi.write(0xFF);
tosihisa 0:e0ec137da369 151 }
tosihisa 0:e0ec137da369 152
tosihisa 0:e0ec137da369 153 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
tosihisa 0:e0ec137da369 154 if(_cmd(0, 0) != R1_IDLE_STATE) {
tosihisa 0:e0ec137da369 155 fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
tosihisa 0:e0ec137da369 156 return SDCARD_FAIL;
tosihisa 0:e0ec137da369 157 }
tosihisa 0:e0ec137da369 158
tosihisa 0:e0ec137da369 159 // send CMD8 to determine whther it is ver 2.x
tosihisa 0:e0ec137da369 160 int r = _cmd8();
tosihisa 0:e0ec137da369 161 if(r == R1_IDLE_STATE) {
tosihisa 0:e0ec137da369 162 return initialise_card_v2();
tosihisa 0:e0ec137da369 163 } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
tosihisa 0:e0ec137da369 164 return initialise_card_v1();
tosihisa 0:e0ec137da369 165 } else {
tosihisa 0:e0ec137da369 166 fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
tosihisa 0:e0ec137da369 167 return SDCARD_FAIL;
tosihisa 0:e0ec137da369 168 }
tosihisa 0:e0ec137da369 169 }
tosihisa 0:e0ec137da369 170
tosihisa 0:e0ec137da369 171 int SDFileSystem::initialise_card_v1() {
tosihisa 0:e0ec137da369 172 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tosihisa 0:e0ec137da369 173 _cmd(55, 0);
tosihisa 0:e0ec137da369 174 if(_cmd(41, 0) == 0) {
tosihisa 0:e0ec137da369 175 return SDCARD_V1;
tosihisa 0:e0ec137da369 176 }
tosihisa 0:e0ec137da369 177 }
tosihisa 0:e0ec137da369 178
tosihisa 0:e0ec137da369 179 fprintf(stderr, "Timeout waiting for v1.x card\n");
tosihisa 0:e0ec137da369 180 return SDCARD_FAIL;
tosihisa 0:e0ec137da369 181 }
tosihisa 0:e0ec137da369 182
tosihisa 0:e0ec137da369 183 int SDFileSystem::initialise_card_v2() {
tosihisa 0:e0ec137da369 184
tosihisa 0:e0ec137da369 185 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tosihisa 0:e0ec137da369 186 _cmd(55, 0);
tosihisa 0:e0ec137da369 187 if(_cmd(41, 0) == 0) {
tosihisa 0:e0ec137da369 188 _cmd58();
tosihisa 0:e0ec137da369 189 return SDCARD_V2;
tosihisa 0:e0ec137da369 190 }
tosihisa 0:e0ec137da369 191 }
tosihisa 0:e0ec137da369 192
tosihisa 0:e0ec137da369 193 fprintf(stderr, "Timeout waiting for v2.x card\n");
tosihisa 0:e0ec137da369 194 return SDCARD_FAIL;
tosihisa 0:e0ec137da369 195 }
tosihisa 0:e0ec137da369 196
tosihisa 0:e0ec137da369 197 int SDFileSystem::disk_initialize() {
tosihisa 0:e0ec137da369 198
tosihisa 0:e0ec137da369 199 int i = initialise_card();
tosihisa 0:e0ec137da369 200 // printf("init card = %d\n", i);
tosihisa 0:e0ec137da369 201 // printf("OK\n");
tosihisa 0:e0ec137da369 202
tosihisa 0:e0ec137da369 203 _sectors = _sd_sectors();
tosihisa 0:e0ec137da369 204
tosihisa 0:e0ec137da369 205 // Set block length to 512 (CMD16)
tosihisa 0:e0ec137da369 206 if(_cmd(16, 512) != 0) {
tosihisa 0:e0ec137da369 207 fprintf(stderr, "Set 512-byte block timed out\n");
tosihisa 0:e0ec137da369 208 return 1;
tosihisa 0:e0ec137da369 209 }
tosihisa 0:e0ec137da369 210
tosihisa 0:e0ec137da369 211 _spi.frequency(1000000); // Set to 1MHz for data transfer
tosihisa 0:e0ec137da369 212 return 0;
tosihisa 0:e0ec137da369 213 }
tosihisa 0:e0ec137da369 214
tosihisa 0:e0ec137da369 215 int SDFileSystem::disk_write(const char *buffer, int block_number) {
tosihisa 0:e0ec137da369 216 // set write address for single block (CMD24)
tosihisa 0:e0ec137da369 217 if(_cmd(24, block_number * 512) != 0) {
tosihisa 0:e0ec137da369 218 return 1;
tosihisa 0:e0ec137da369 219 }
tosihisa 0:e0ec137da369 220
tosihisa 0:e0ec137da369 221 // send the data block
tosihisa 0:e0ec137da369 222 _write(buffer, 512);
tosihisa 0:e0ec137da369 223 return 0;
tosihisa 0:e0ec137da369 224 }
tosihisa 0:e0ec137da369 225
tosihisa 0:e0ec137da369 226 int SDFileSystem::disk_read(char *buffer, int block_number) {
tosihisa 0:e0ec137da369 227 // set read address for single block (CMD17)
tosihisa 0:e0ec137da369 228 if(_cmd(17, block_number * 512) != 0) {
tosihisa 0:e0ec137da369 229 return 1;
tosihisa 0:e0ec137da369 230 }
tosihisa 0:e0ec137da369 231
tosihisa 0:e0ec137da369 232 // receive the data
tosihisa 0:e0ec137da369 233 _read(buffer, 512);
tosihisa 0:e0ec137da369 234 return 0;
tosihisa 0:e0ec137da369 235 }
tosihisa 0:e0ec137da369 236
tosihisa 0:e0ec137da369 237 int SDFileSystem::disk_status() { return 0; }
tosihisa 0:e0ec137da369 238 int SDFileSystem::disk_sync() { return 0; }
tosihisa 0:e0ec137da369 239 int SDFileSystem::disk_sectors() { return _sectors; }
tosihisa 0:e0ec137da369 240
tosihisa 0:e0ec137da369 241 // PRIVATE FUNCTIONS
tosihisa 0:e0ec137da369 242
tosihisa 0:e0ec137da369 243 int SDFileSystem::_cmd(int cmd, int arg) {
tosihisa 0:e0ec137da369 244 _cs = 0;
tosihisa 0:e0ec137da369 245
tosihisa 0:e0ec137da369 246 // send a command
tosihisa 0:e0ec137da369 247 _spi.write(0x40 | cmd);
tosihisa 0:e0ec137da369 248 _spi.write(arg >> 24);
tosihisa 0:e0ec137da369 249 _spi.write(arg >> 16);
tosihisa 0:e0ec137da369 250 _spi.write(arg >> 8);
tosihisa 0:e0ec137da369 251 _spi.write(arg >> 0);
tosihisa 0:e0ec137da369 252 _spi.write(0x95);
tosihisa 0:e0ec137da369 253
tosihisa 0:e0ec137da369 254 // wait for the repsonse (response[7] == 0)
tosihisa 0:e0ec137da369 255 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tosihisa 0:e0ec137da369 256 int response = _spi.write(0xFF);
tosihisa 0:e0ec137da369 257 if(!(response & 0x80)) {
tosihisa 0:e0ec137da369 258 _cs = 1;
tosihisa 0:e0ec137da369 259 _spi.write(0xFF);
tosihisa 0:e0ec137da369 260 return response;
tosihisa 0:e0ec137da369 261 }
tosihisa 0:e0ec137da369 262 }
tosihisa 0:e0ec137da369 263 _cs = 1;
tosihisa 0:e0ec137da369 264 _spi.write(0xFF);
tosihisa 0:e0ec137da369 265 return -1; // timeout
tosihisa 0:e0ec137da369 266 }
tosihisa 0:e0ec137da369 267 int SDFileSystem::_cmdx(int cmd, int arg) {
tosihisa 0:e0ec137da369 268 _cs = 0;
tosihisa 0:e0ec137da369 269
tosihisa 0:e0ec137da369 270 // send a command
tosihisa 0:e0ec137da369 271 _spi.write(0x40 | cmd);
tosihisa 0:e0ec137da369 272 _spi.write(arg >> 24);
tosihisa 0:e0ec137da369 273 _spi.write(arg >> 16);
tosihisa 0:e0ec137da369 274 _spi.write(arg >> 8);
tosihisa 0:e0ec137da369 275 _spi.write(arg >> 0);
tosihisa 0:e0ec137da369 276 _spi.write(0x95);
tosihisa 0:e0ec137da369 277
tosihisa 0:e0ec137da369 278 // wait for the repsonse (response[7] == 0)
tosihisa 0:e0ec137da369 279 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tosihisa 0:e0ec137da369 280 int response = _spi.write(0xFF);
tosihisa 0:e0ec137da369 281 if(!(response & 0x80)) {
tosihisa 0:e0ec137da369 282 return response;
tosihisa 0:e0ec137da369 283 }
tosihisa 0:e0ec137da369 284 }
tosihisa 0:e0ec137da369 285 _cs = 1;
tosihisa 0:e0ec137da369 286 _spi.write(0xFF);
tosihisa 0:e0ec137da369 287 return -1; // timeout
tosihisa 0:e0ec137da369 288 }
tosihisa 0:e0ec137da369 289
tosihisa 0:e0ec137da369 290
tosihisa 0:e0ec137da369 291 int SDFileSystem::_cmd58() {
tosihisa 0:e0ec137da369 292 _cs = 0;
tosihisa 0:e0ec137da369 293 int arg = 0;
tosihisa 0:e0ec137da369 294
tosihisa 0:e0ec137da369 295 // send a command
tosihisa 0:e0ec137da369 296 _spi.write(0x40 | 58);
tosihisa 0:e0ec137da369 297 _spi.write(arg >> 24);
tosihisa 0:e0ec137da369 298 _spi.write(arg >> 16);
tosihisa 0:e0ec137da369 299 _spi.write(arg >> 8);
tosihisa 0:e0ec137da369 300 _spi.write(arg >> 0);
tosihisa 0:e0ec137da369 301 _spi.write(0x95);
tosihisa 0:e0ec137da369 302
tosihisa 0:e0ec137da369 303 // wait for the repsonse (response[7] == 0)
tosihisa 0:e0ec137da369 304 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
tosihisa 0:e0ec137da369 305 int response = _spi.write(0xFF);
tosihisa 0:e0ec137da369 306 if(!(response & 0x80)) {
tosihisa 0:e0ec137da369 307 int ocr = _spi.write(0xFF) << 24;
tosihisa 0:e0ec137da369 308 ocr |= _spi.write(0xFF) << 16;
tosihisa 0:e0ec137da369 309 ocr |= _spi.write(0xFF) << 8;
tosihisa 0:e0ec137da369 310 ocr |= _spi.write(0xFF) << 0;
tosihisa 0:e0ec137da369 311 // printf("OCR = 0x%08X\n", ocr);
tosihisa 0:e0ec137da369 312 _cs = 1;
tosihisa 0:e0ec137da369 313 _spi.write(0xFF);
tosihisa 0:e0ec137da369 314 return response;
tosihisa 0:e0ec137da369 315 }
tosihisa 0:e0ec137da369 316 }
tosihisa 0:e0ec137da369 317 _cs = 1;
tosihisa 0:e0ec137da369 318 _spi.write(0xFF);
tosihisa 0:e0ec137da369 319 return -1; // timeout
tosihisa 0:e0ec137da369 320 }
tosihisa 0:e0ec137da369 321
tosihisa 0:e0ec137da369 322 int SDFileSystem::_cmd8() {
tosihisa 0:e0ec137da369 323 _cs = 0;
tosihisa 0:e0ec137da369 324
tosihisa 0:e0ec137da369 325 // send a command
tosihisa 0:e0ec137da369 326 _spi.write(0x40 | 8); // CMD8
tosihisa 0:e0ec137da369 327 _spi.write(0x00); // reserved
tosihisa 0:e0ec137da369 328 _spi.write(0x00); // reserved
tosihisa 0:e0ec137da369 329 _spi.write(0x01); // 3.3v
tosihisa 0:e0ec137da369 330 _spi.write(0xAA); // check pattern
tosihisa 0:e0ec137da369 331 _spi.write(0x87); // crc
tosihisa 0:e0ec137da369 332
tosihisa 0:e0ec137da369 333 // wait for the repsonse (response[7] == 0)
tosihisa 0:e0ec137da369 334 for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
tosihisa 0:e0ec137da369 335 char response[5];
tosihisa 0:e0ec137da369 336 response[0] = _spi.write(0xFF);
tosihisa 0:e0ec137da369 337 if(!(response[0] & 0x80)) {
tosihisa 0:e0ec137da369 338 for(int j=1; j<5; j++) {
tosihisa 0:e0ec137da369 339 response[i] = _spi.write(0xFF);
tosihisa 0:e0ec137da369 340 }
tosihisa 0:e0ec137da369 341 _cs = 1;
tosihisa 0:e0ec137da369 342 _spi.write(0xFF);
tosihisa 0:e0ec137da369 343 return response[0];
tosihisa 0:e0ec137da369 344 }
tosihisa 0:e0ec137da369 345 }
tosihisa 0:e0ec137da369 346 _cs = 1;
tosihisa 0:e0ec137da369 347 _spi.write(0xFF);
tosihisa 0:e0ec137da369 348 return -1; // timeout
tosihisa 0:e0ec137da369 349 }
tosihisa 0:e0ec137da369 350
tosihisa 0:e0ec137da369 351 int SDFileSystem::_read(char *buffer, int length) {
tosihisa 0:e0ec137da369 352 _cs = 0;
tosihisa 0:e0ec137da369 353
tosihisa 0:e0ec137da369 354 // read until start byte (0xFF)
tosihisa 0:e0ec137da369 355 while(_spi.write(0xFF) != 0xFE);
tosihisa 0:e0ec137da369 356
tosihisa 0:e0ec137da369 357 // read data
tosihisa 0:e0ec137da369 358 for(int i=0; i<length; i++) {
tosihisa 0:e0ec137da369 359 buffer[i] = _spi.write(0xFF);
tosihisa 0:e0ec137da369 360 }
tosihisa 0:e0ec137da369 361 _spi.write(0xFF); // checksum
tosihisa 0:e0ec137da369 362 _spi.write(0xFF);
tosihisa 0:e0ec137da369 363
tosihisa 0:e0ec137da369 364 _cs = 1;
tosihisa 0:e0ec137da369 365 _spi.write(0xFF);
tosihisa 0:e0ec137da369 366 return 0;
tosihisa 0:e0ec137da369 367 }
tosihisa 0:e0ec137da369 368
tosihisa 0:e0ec137da369 369 int SDFileSystem::_write(const char *buffer, int length) {
tosihisa 0:e0ec137da369 370 _cs = 0;
tosihisa 0:e0ec137da369 371
tosihisa 0:e0ec137da369 372 // indicate start of block
tosihisa 0:e0ec137da369 373 _spi.write(0xFE);
tosihisa 0:e0ec137da369 374
tosihisa 0:e0ec137da369 375 // write the data
tosihisa 0:e0ec137da369 376 for(int i=0; i<length; i++) {
tosihisa 0:e0ec137da369 377 _spi.write(buffer[i]);
tosihisa 0:e0ec137da369 378 }
tosihisa 0:e0ec137da369 379
tosihisa 0:e0ec137da369 380 // write the checksum
tosihisa 0:e0ec137da369 381 _spi.write(0xFF);
tosihisa 0:e0ec137da369 382 _spi.write(0xFF);
tosihisa 0:e0ec137da369 383
tosihisa 0:e0ec137da369 384 // check the repsonse token
tosihisa 0:e0ec137da369 385 if((_spi.write(0xFF) & 0x1F) != 0x05) {
tosihisa 0:e0ec137da369 386 _cs = 1;
tosihisa 0:e0ec137da369 387 _spi.write(0xFF);
tosihisa 0:e0ec137da369 388 return 1;
tosihisa 0:e0ec137da369 389 }
tosihisa 0:e0ec137da369 390
tosihisa 0:e0ec137da369 391 // wait for write to finish
tosihisa 0:e0ec137da369 392 while(_spi.write(0xFF) == 0);
tosihisa 0:e0ec137da369 393
tosihisa 0:e0ec137da369 394 _cs = 1;
tosihisa 0:e0ec137da369 395 _spi.write(0xFF);
tosihisa 0:e0ec137da369 396 return 0;
tosihisa 0:e0ec137da369 397 }
tosihisa 0:e0ec137da369 398
tosihisa 0:e0ec137da369 399 static int ext_bits(char *data, int msb, int lsb) {
tosihisa 0:e0ec137da369 400 int bits = 0;
tosihisa 0:e0ec137da369 401 int size = 1 + msb - lsb;
tosihisa 0:e0ec137da369 402 for(int i=0; i<size; i++) {
tosihisa 0:e0ec137da369 403 int position = lsb + i;
tosihisa 0:e0ec137da369 404 int byte = 15 - (position >> 3);
tosihisa 0:e0ec137da369 405 int bit = position & 0x7;
tosihisa 0:e0ec137da369 406 int value = (data[byte] >> bit) & 1;
tosihisa 0:e0ec137da369 407 bits |= value << i;
tosihisa 0:e0ec137da369 408 }
tosihisa 0:e0ec137da369 409 return bits;
tosihisa 0:e0ec137da369 410 }
tosihisa 0:e0ec137da369 411
tosihisa 0:e0ec137da369 412 int SDFileSystem::_sd_sectors() {
tosihisa 0:e0ec137da369 413
tosihisa 0:e0ec137da369 414 // CMD9, Response R2 (R1 byte + 16-byte block read)
tosihisa 0:e0ec137da369 415 if(_cmdx(9, 0) != 0) {
tosihisa 0:e0ec137da369 416 fprintf(stderr, "Didn't get a response from the disk\n");
tosihisa 0:e0ec137da369 417 return 0;
tosihisa 0:e0ec137da369 418 }
tosihisa 0:e0ec137da369 419
tosihisa 0:e0ec137da369 420 char csd[16];
tosihisa 0:e0ec137da369 421 if(_read(csd, 16) != 0) {
tosihisa 0:e0ec137da369 422 fprintf(stderr, "Couldn't read csd response from disk\n");
tosihisa 0:e0ec137da369 423 return 0;
tosihisa 0:e0ec137da369 424 }
tosihisa 0:e0ec137da369 425
tosihisa 0:e0ec137da369 426 // csd_structure : csd[127:126]
tosihisa 0:e0ec137da369 427 // c_size : csd[73:62]
tosihisa 0:e0ec137da369 428 // c_size_mult : csd[49:47]
tosihisa 0:e0ec137da369 429 // read_bl_len : csd[83:80] - the *maximum* read block length
tosihisa 0:e0ec137da369 430
tosihisa 0:e0ec137da369 431 int csd_structure = ext_bits(csd, 127, 126);
tosihisa 0:e0ec137da369 432 int c_size = ext_bits(csd, 73, 62);
tosihisa 0:e0ec137da369 433 int c_size_mult = ext_bits(csd, 49, 47);
tosihisa 0:e0ec137da369 434 int read_bl_len = ext_bits(csd, 83, 80);
tosihisa 0:e0ec137da369 435
tosihisa 0:e0ec137da369 436 // printf("CSD_STRUCT = %d\n", csd_structure);
tosihisa 0:e0ec137da369 437
tosihisa 0:e0ec137da369 438 if(csd_structure != 0) {
tosihisa 0:e0ec137da369 439 fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
tosihisa 0:e0ec137da369 440 return 0;
tosihisa 0:e0ec137da369 441 }
tosihisa 0:e0ec137da369 442
tosihisa 0:e0ec137da369 443 // memory capacity = BLOCKNR * BLOCK_LEN
tosihisa 0:e0ec137da369 444 // where
tosihisa 0:e0ec137da369 445 // BLOCKNR = (C_SIZE+1) * MULT
tosihisa 0:e0ec137da369 446 // MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8)
tosihisa 0:e0ec137da369 447 // BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12)
tosihisa 0:e0ec137da369 448
tosihisa 0:e0ec137da369 449 int block_len = 1 << read_bl_len;
tosihisa 0:e0ec137da369 450 int mult = 1 << (c_size_mult + 2);
tosihisa 0:e0ec137da369 451 int blocknr = (c_size + 1) * mult;
tosihisa 0:e0ec137da369 452 int capacity = blocknr * block_len;
tosihisa 0:e0ec137da369 453
tosihisa 0:e0ec137da369 454 int blocks = capacity / 512;
tosihisa 0:e0ec137da369 455
tosihisa 0:e0ec137da369 456 return blocks;
tosihisa 0:e0ec137da369 457 }