Cong Vu / Mbed 2 deprecated Project2_cvu31

SNAKE GAME

Dependencies:   mbed wave_player 4DGL-uLCD-SE MMA8452

SDFileSystem/SDFileSystem.cpp@0:24041b847eb5, 2020-11-25 (annotated)

Committer:
congvu
Date:
Wed Nov 25 04:25:25 2020 +0000
Revision:
0:24041b847eb5
ECE2035 SNAKE GAME;

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congvu 0:24041b847eb5 1 /* mbed Microcontroller Library
congvu 0:24041b847eb5 2 * Copyright (c) 2006-2012 ARM Limited
congvu 0:24041b847eb5 3 *
congvu 0:24041b847eb5 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
congvu 0:24041b847eb5 5 * of this software and associated documentation files (the "Software"), to deal
congvu 0:24041b847eb5 6 * in the Software without restriction, including without limitation the rights
congvu 0:24041b847eb5 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
congvu 0:24041b847eb5 8 * copies of the Software, and to permit persons to whom the Software is
congvu 0:24041b847eb5 9 * furnished to do so, subject to the following conditions:
congvu 0:24041b847eb5 10 *
congvu 0:24041b847eb5 11 * The above copyright notice and this permission notice shall be included in
congvu 0:24041b847eb5 12 * all copies or substantial portions of the Software.
congvu 0:24041b847eb5 13 *
congvu 0:24041b847eb5 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
congvu 0:24041b847eb5 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
congvu 0:24041b847eb5 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
congvu 0:24041b847eb5 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
congvu 0:24041b847eb5 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
congvu 0:24041b847eb5 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
congvu 0:24041b847eb5 20 * SOFTWARE.
congvu 0:24041b847eb5 21 */
congvu 0:24041b847eb5 22 /* Introduction
congvu 0:24041b847eb5 23 * ------------
congvu 0:24041b847eb5 24 * SD and MMC cards support a number of interfaces, but common to them all
congvu 0:24041b847eb5 25 * is one based on SPI. This is the one I'm implmenting because it means
congvu 0:24041b847eb5 26 * it is much more portable even though not so performant, and we already
congvu 0:24041b847eb5 27 * have the mbed SPI Interface!
congvu 0:24041b847eb5 28 *
congvu 0:24041b847eb5 29 * The main reference I'm using is Chapter 7, "SPI Mode" of:
congvu 0:24041b847eb5 30 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
congvu 0:24041b847eb5 31 *
congvu 0:24041b847eb5 32 * SPI Startup
congvu 0:24041b847eb5 33 * -----------
congvu 0:24041b847eb5 34 * The SD card powers up in SD mode. The SPI interface mode is selected by
congvu 0:24041b847eb5 35 * asserting CS low and sending the reset command (CMD0). The card will
congvu 0:24041b847eb5 36 * respond with a (R1) response.
congvu 0:24041b847eb5 37 *
congvu 0:24041b847eb5 38 * CMD8 is optionally sent to determine the voltage range supported, and
congvu 0:24041b847eb5 39 * indirectly determine whether it is a version 1.x SD/non-SD card or
congvu 0:24041b847eb5 40 * version 2.x. I'll just ignore this for now.
congvu 0:24041b847eb5 41 *
congvu 0:24041b847eb5 42 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
congvu 0:24041b847eb5 43 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
congvu 0:24041b847eb5 44 *
congvu 0:24041b847eb5 45 * You should also indicate whether the host supports High Capicity cards,
congvu 0:24041b847eb5 46 * and check whether the card is high capacity - i'll also ignore this
congvu 0:24041b847eb5 47 *
congvu 0:24041b847eb5 48 * SPI Protocol
congvu 0:24041b847eb5 49 * ------------
congvu 0:24041b847eb5 50 * The SD SPI protocol is based on transactions made up of 8-bit words, with
congvu 0:24041b847eb5 51 * the host starting every bus transaction by asserting the CS signal low. The
congvu 0:24041b847eb5 52 * card always responds to commands, data blocks and errors.
congvu 0:24041b847eb5 53 *
congvu 0:24041b847eb5 54 * The protocol supports a CRC, but by default it is off (except for the
congvu 0:24041b847eb5 55 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
congvu 0:24041b847eb5 56 * I'll leave the CRC off I think!
congvu 0:24041b847eb5 57 *
congvu 0:24041b847eb5 58 * Standard capacity cards have variable data block sizes, whereas High
congvu 0:24041b847eb5 59 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
congvu 0:24041b847eb5 60 * just always use the Standard Capacity cards with a block size of 512 bytes.
congvu 0:24041b847eb5 61 * This is set with CMD16.
congvu 0:24041b847eb5 62 *
congvu 0:24041b847eb5 63 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
congvu 0:24041b847eb5 64 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
congvu 0:24041b847eb5 65 * the card gets a read command, it responds with a response token, and then
congvu 0:24041b847eb5 66 * a data token or an error.
congvu 0:24041b847eb5 67 *
congvu 0:24041b847eb5 68 * SPI Command Format
congvu 0:24041b847eb5 69 * ------------------
congvu 0:24041b847eb5 70 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
congvu 0:24041b847eb5 71 *
congvu 0:24041b847eb5 72 * +---------------+------------+------------+-----------+----------+--------------+
congvu 0:24041b847eb5 73 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
congvu 0:24041b847eb5 74 * +---------------+------------+------------+-----------+----------+--------------+
congvu 0:24041b847eb5 75 *
congvu 0:24041b847eb5 76 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
congvu 0:24041b847eb5 77 *
congvu 0:24041b847eb5 78 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
congvu 0:24041b847eb5 79 *
congvu 0:24041b847eb5 80 * SPI Response Format
congvu 0:24041b847eb5 81 * -------------------
congvu 0:24041b847eb5 82 * The main response format (R1) is a status byte (normally zero). Key flags:
congvu 0:24041b847eb5 83 * idle - 1 if the card is in an idle state/initialising
congvu 0:24041b847eb5 84 * cmd - 1 if an illegal command code was detected
congvu 0:24041b847eb5 85 *
congvu 0:24041b847eb5 86 * +-------------------------------------------------+
congvu 0:24041b847eb5 87 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
congvu 0:24041b847eb5 88 * +-------------------------------------------------+
congvu 0:24041b847eb5 89 *
congvu 0:24041b847eb5 90 * R1b is the same, except it is followed by a busy signal (zeros) until
congvu 0:24041b847eb5 91 * the first non-zero byte when it is ready again.
congvu 0:24041b847eb5 92 *
congvu 0:24041b847eb5 93 * Data Response Token
congvu 0:24041b847eb5 94 * -------------------
congvu 0:24041b847eb5 95 * Every data block written to the card is acknowledged by a byte
congvu 0:24041b847eb5 96 * response token
congvu 0:24041b847eb5 97 *
congvu 0:24041b847eb5 98 * +----------------------+
congvu 0:24041b847eb5 99 * | xxx | 0 | status | 1 |
congvu 0:24041b847eb5 100 * +----------------------+
congvu 0:24041b847eb5 101 * 010 - OK!
congvu 0:24041b847eb5 102 * 101 - CRC Error
congvu 0:24041b847eb5 103 * 110 - Write Error
congvu 0:24041b847eb5 104 *
congvu 0:24041b847eb5 105 * Single Block Read and Write
congvu 0:24041b847eb5 106 * ---------------------------
congvu 0:24041b847eb5 107 *
congvu 0:24041b847eb5 108 * Block transfers have a byte header, followed by the data, followed
congvu 0:24041b847eb5 109 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
congvu 0:24041b847eb5 110 *
congvu 0:24041b847eb5 111 * +------+---------+---------+- - - -+---------+-----------+----------+
congvu 0:24041b847eb5 112 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
congvu 0:24041b847eb5 113 * +------+---------+---------+- - - -+---------+-----------+----------+
congvu 0:24041b847eb5 114 */
congvu 0:24041b847eb5 115 #include "SDFileSystem.h"
congvu 0:24041b847eb5 116 #include "mbed_debug.h"
congvu 0:24041b847eb5 117
congvu 0:24041b847eb5 118 #define SD_COMMAND_TIMEOUT 5000
congvu 0:24041b847eb5 119
congvu 0:24041b847eb5 120 #define SD_DBG 0
congvu 0:24041b847eb5 121
congvu 0:24041b847eb5 122 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
congvu 0:24041b847eb5 123 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
congvu 0:24041b847eb5 124 _cs = 1;
congvu 0:24041b847eb5 125 }
congvu 0:24041b847eb5 126
congvu 0:24041b847eb5 127 #define R1_IDLE_STATE (1 << 0)
congvu 0:24041b847eb5 128 #define R1_ERASE_RESET (1 << 1)
congvu 0:24041b847eb5 129 #define R1_ILLEGAL_COMMAND (1 << 2)
congvu 0:24041b847eb5 130 #define R1_COM_CRC_ERROR (1 << 3)
congvu 0:24041b847eb5 131 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
congvu 0:24041b847eb5 132 #define R1_ADDRESS_ERROR (1 << 5)
congvu 0:24041b847eb5 133 #define R1_PARAMETER_ERROR (1 << 6)
congvu 0:24041b847eb5 134
congvu 0:24041b847eb5 135 // Types
congvu 0:24041b847eb5 136 // - v1.x Standard Capacity
congvu 0:24041b847eb5 137 // - v2.x Standard Capacity
congvu 0:24041b847eb5 138 // - v2.x High Capacity
congvu 0:24041b847eb5 139 // - Not recognised as an SD Card
congvu 0:24041b847eb5 140 #define SDCARD_FAIL 0
congvu 0:24041b847eb5 141 #define SDCARD_V1 1
congvu 0:24041b847eb5 142 #define SDCARD_V2 2
congvu 0:24041b847eb5 143 #define SDCARD_V2HC 3
congvu 0:24041b847eb5 144
congvu 0:24041b847eb5 145 int SDFileSystem::initialise_card() {
congvu 0:24041b847eb5 146 // Set to 100kHz for initialisation, and clock card with cs = 1
congvu 0:24041b847eb5 147 _spi.frequency(100000);
congvu 0:24041b847eb5 148 _cs = 1;
congvu 0:24041b847eb5 149 for (int i = 0; i < 16; i++) {
congvu 0:24041b847eb5 150 _spi.write(0xFF);
congvu 0:24041b847eb5 151 }
congvu 0:24041b847eb5 152
congvu 0:24041b847eb5 153 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
congvu 0:24041b847eb5 154 if (_cmd(0, 0) != R1_IDLE_STATE) {
congvu 0:24041b847eb5 155 debug("No disk, or could not put SD card in to SPI idle state\n");
congvu 0:24041b847eb5 156 return SDCARD_FAIL;
congvu 0:24041b847eb5 157 }
congvu 0:24041b847eb5 158
congvu 0:24041b847eb5 159 // send CMD8 to determine whther it is ver 2.x
congvu 0:24041b847eb5 160 int r = _cmd8();
congvu 0:24041b847eb5 161 if (r == R1_IDLE_STATE) {
congvu 0:24041b847eb5 162 return initialise_card_v2();
congvu 0:24041b847eb5 163 } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
congvu 0:24041b847eb5 164 return initialise_card_v1();
congvu 0:24041b847eb5 165 } else {
congvu 0:24041b847eb5 166 debug("Not in idle state after sending CMD8 (not an SD card?)\n");
congvu 0:24041b847eb5 167 return SDCARD_FAIL;
congvu 0:24041b847eb5 168 }
congvu 0:24041b847eb5 169 }
congvu 0:24041b847eb5 170
congvu 0:24041b847eb5 171 int SDFileSystem::initialise_card_v1() {
congvu 0:24041b847eb5 172 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
congvu 0:24041b847eb5 173 _cmd(55, 0);
congvu 0:24041b847eb5 174 if (_cmd(41, 0) == 0) {
congvu 0:24041b847eb5 175 cdv = 512;
congvu 0:24041b847eb5 176 debug_if(SD_DBG, "\n\rInit: SEDCARD_V1\n\r");
congvu 0:24041b847eb5 177 return SDCARD_V1;
congvu 0:24041b847eb5 178 }
congvu 0:24041b847eb5 179 }
congvu 0:24041b847eb5 180
congvu 0:24041b847eb5 181 debug("Timeout waiting for v1.x card\n");
congvu 0:24041b847eb5 182 return SDCARD_FAIL;
congvu 0:24041b847eb5 183 }
congvu 0:24041b847eb5 184
congvu 0:24041b847eb5 185 int SDFileSystem::initialise_card_v2() {
congvu 0:24041b847eb5 186 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
congvu 0:24041b847eb5 187 wait_ms(50);
congvu 0:24041b847eb5 188 _cmd58();
congvu 0:24041b847eb5 189 _cmd(55, 0);
congvu 0:24041b847eb5 190 if (_cmd(41, 0x40000000) == 0) {
congvu 0:24041b847eb5 191 _cmd58();
congvu 0:24041b847eb5 192 debug_if(SD_DBG, "\n\rInit: SDCARD_V2\n\r");
congvu 0:24041b847eb5 193 cdv = 1;
congvu 0:24041b847eb5 194 return SDCARD_V2;
congvu 0:24041b847eb5 195 }
congvu 0:24041b847eb5 196 }
congvu 0:24041b847eb5 197
congvu 0:24041b847eb5 198 debug("Timeout waiting for v2.x card\n");
congvu 0:24041b847eb5 199 return SDCARD_FAIL;
congvu 0:24041b847eb5 200 }
congvu 0:24041b847eb5 201
congvu 0:24041b847eb5 202 int SDFileSystem::disk_initialize() {
congvu 0:24041b847eb5 203 int i = initialise_card();
congvu 0:24041b847eb5 204 debug_if(SD_DBG, "init card = %d\n", i);
congvu 0:24041b847eb5 205 _sectors = _sd_sectors();
congvu 0:24041b847eb5 206
congvu 0:24041b847eb5 207 // Set block length to 512 (CMD16)
congvu 0:24041b847eb5 208 if (_cmd(16, 512) != 0) {
congvu 0:24041b847eb5 209 debug("Set 512-byte block timed out\n");
congvu 0:24041b847eb5 210 return 1;
congvu 0:24041b847eb5 211 }
congvu 0:24041b847eb5 212
congvu 0:24041b847eb5 213 _spi.frequency(1000000); // Set to 1MHz for data transfer
congvu 0:24041b847eb5 214 return 0;
congvu 0:24041b847eb5 215 }
congvu 0:24041b847eb5 216
congvu 0:24041b847eb5 217 int SDFileSystem::disk_write(const uint8_t *buffer, uint64_t block_number) {
congvu 0:24041b847eb5 218 // set write address for single block (CMD24)
congvu 0:24041b847eb5 219 if (_cmd(24, block_number * cdv) != 0) {
congvu 0:24041b847eb5 220 return 1;
congvu 0:24041b847eb5 221 }
congvu 0:24041b847eb5 222
congvu 0:24041b847eb5 223 // send the data block
congvu 0:24041b847eb5 224 _write(buffer, 512);
congvu 0:24041b847eb5 225 return 0;
congvu 0:24041b847eb5 226 }
congvu 0:24041b847eb5 227
congvu 0:24041b847eb5 228 int SDFileSystem::disk_read(uint8_t *buffer, uint64_t block_number) {
congvu 0:24041b847eb5 229 // set read address for single block (CMD17)
congvu 0:24041b847eb5 230 if (_cmd(17, block_number * cdv) != 0) {
congvu 0:24041b847eb5 231 return 1;
congvu 0:24041b847eb5 232 }
congvu 0:24041b847eb5 233
congvu 0:24041b847eb5 234 // receive the data
congvu 0:24041b847eb5 235 _read(buffer, 512);
congvu 0:24041b847eb5 236 return 0;
congvu 0:24041b847eb5 237 }
congvu 0:24041b847eb5 238
congvu 0:24041b847eb5 239 int SDFileSystem::disk_status() { return 0; }
congvu 0:24041b847eb5 240 int SDFileSystem::disk_sync() { return 0; }
congvu 0:24041b847eb5 241 uint64_t SDFileSystem::disk_sectors() { return _sectors; }
congvu 0:24041b847eb5 242
congvu 0:24041b847eb5 243
congvu 0:24041b847eb5 244 // PRIVATE FUNCTIONS
congvu 0:24041b847eb5 245 int SDFileSystem::_cmd(int cmd, int arg) {
congvu 0:24041b847eb5 246 _cs = 0;
congvu 0:24041b847eb5 247
congvu 0:24041b847eb5 248 // send a command
congvu 0:24041b847eb5 249 _spi.write(0x40 | cmd);
congvu 0:24041b847eb5 250 _spi.write(arg >> 24);
congvu 0:24041b847eb5 251 _spi.write(arg >> 16);
congvu 0:24041b847eb5 252 _spi.write(arg >> 8);
congvu 0:24041b847eb5 253 _spi.write(arg >> 0);
congvu 0:24041b847eb5 254 _spi.write(0x95);
congvu 0:24041b847eb5 255
congvu 0:24041b847eb5 256 // wait for the repsonse (response[7] == 0)
congvu 0:24041b847eb5 257 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
congvu 0:24041b847eb5 258 int response = _spi.write(0xFF);
congvu 0:24041b847eb5 259 if (!(response & 0x80)) {
congvu 0:24041b847eb5 260 _cs = 1;
congvu 0:24041b847eb5 261 _spi.write(0xFF);
congvu 0:24041b847eb5 262 return response;
congvu 0:24041b847eb5 263 }
congvu 0:24041b847eb5 264 }
congvu 0:24041b847eb5 265 _cs = 1;
congvu 0:24041b847eb5 266 _spi.write(0xFF);
congvu 0:24041b847eb5 267 return -1; // timeout
congvu 0:24041b847eb5 268 }
congvu 0:24041b847eb5 269 int SDFileSystem::_cmdx(int cmd, int arg) {
congvu 0:24041b847eb5 270 _cs = 0;
congvu 0:24041b847eb5 271
congvu 0:24041b847eb5 272 // send a command
congvu 0:24041b847eb5 273 _spi.write(0x40 | cmd);
congvu 0:24041b847eb5 274 _spi.write(arg >> 24);
congvu 0:24041b847eb5 275 _spi.write(arg >> 16);
congvu 0:24041b847eb5 276 _spi.write(arg >> 8);
congvu 0:24041b847eb5 277 _spi.write(arg >> 0);
congvu 0:24041b847eb5 278 _spi.write(0x95);
congvu 0:24041b847eb5 279
congvu 0:24041b847eb5 280 // wait for the repsonse (response[7] == 0)
congvu 0:24041b847eb5 281 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
congvu 0:24041b847eb5 282 int response = _spi.write(0xFF);
congvu 0:24041b847eb5 283 if (!(response & 0x80)) {
congvu 0:24041b847eb5 284 return response;
congvu 0:24041b847eb5 285 }
congvu 0:24041b847eb5 286 }
congvu 0:24041b847eb5 287 _cs = 1;
congvu 0:24041b847eb5 288 _spi.write(0xFF);
congvu 0:24041b847eb5 289 return -1; // timeout
congvu 0:24041b847eb5 290 }
congvu 0:24041b847eb5 291
congvu 0:24041b847eb5 292
congvu 0:24041b847eb5 293 int SDFileSystem::_cmd58() {
congvu 0:24041b847eb5 294 _cs = 0;
congvu 0:24041b847eb5 295 int arg = 0;
congvu 0:24041b847eb5 296
congvu 0:24041b847eb5 297 // send a command
congvu 0:24041b847eb5 298 _spi.write(0x40 | 58);
congvu 0:24041b847eb5 299 _spi.write(arg >> 24);
congvu 0:24041b847eb5 300 _spi.write(arg >> 16);
congvu 0:24041b847eb5 301 _spi.write(arg >> 8);
congvu 0:24041b847eb5 302 _spi.write(arg >> 0);
congvu 0:24041b847eb5 303 _spi.write(0x95);
congvu 0:24041b847eb5 304
congvu 0:24041b847eb5 305 // wait for the repsonse (response[7] == 0)
congvu 0:24041b847eb5 306 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
congvu 0:24041b847eb5 307 int response = _spi.write(0xFF);
congvu 0:24041b847eb5 308 if (!(response & 0x80)) {
congvu 0:24041b847eb5 309 int ocr = _spi.write(0xFF) << 24;
congvu 0:24041b847eb5 310 ocr |= _spi.write(0xFF) << 16;
congvu 0:24041b847eb5 311 ocr |= _spi.write(0xFF) << 8;
congvu 0:24041b847eb5 312 ocr |= _spi.write(0xFF) << 0;
congvu 0:24041b847eb5 313 _cs = 1;
congvu 0:24041b847eb5 314 _spi.write(0xFF);
congvu 0:24041b847eb5 315 return response;
congvu 0:24041b847eb5 316 }
congvu 0:24041b847eb5 317 }
congvu 0:24041b847eb5 318 _cs = 1;
congvu 0:24041b847eb5 319 _spi.write(0xFF);
congvu 0:24041b847eb5 320 return -1; // timeout
congvu 0:24041b847eb5 321 }
congvu 0:24041b847eb5 322
congvu 0:24041b847eb5 323 int SDFileSystem::_cmd8() {
congvu 0:24041b847eb5 324 _cs = 0;
congvu 0:24041b847eb5 325
congvu 0:24041b847eb5 326 // send a command
congvu 0:24041b847eb5 327 _spi.write(0x40 | 8); // CMD8
congvu 0:24041b847eb5 328 _spi.write(0x00); // reserved
congvu 0:24041b847eb5 329 _spi.write(0x00); // reserved
congvu 0:24041b847eb5 330 _spi.write(0x01); // 3.3v
congvu 0:24041b847eb5 331 _spi.write(0xAA); // check pattern
congvu 0:24041b847eb5 332 _spi.write(0x87); // crc
congvu 0:24041b847eb5 333
congvu 0:24041b847eb5 334 // wait for the repsonse (response[7] == 0)
congvu 0:24041b847eb5 335 for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
congvu 0:24041b847eb5 336 char response[5];
congvu 0:24041b847eb5 337 response[0] = _spi.write(0xFF);
congvu 0:24041b847eb5 338 if (!(response[0] & 0x80)) {
congvu 0:24041b847eb5 339 for (int j = 1; j < 5; j++) {
congvu 0:24041b847eb5 340 response[i] = _spi.write(0xFF);
congvu 0:24041b847eb5 341 }
congvu 0:24041b847eb5 342 _cs = 1;
congvu 0:24041b847eb5 343 _spi.write(0xFF);
congvu 0:24041b847eb5 344 return response[0];
congvu 0:24041b847eb5 345 }
congvu 0:24041b847eb5 346 }
congvu 0:24041b847eb5 347 _cs = 1;
congvu 0:24041b847eb5 348 _spi.write(0xFF);
congvu 0:24041b847eb5 349 return -1; // timeout
congvu 0:24041b847eb5 350 }
congvu 0:24041b847eb5 351
congvu 0:24041b847eb5 352 int SDFileSystem::_read(uint8_t *buffer, uint32_t length) {
congvu 0:24041b847eb5 353 _cs = 0;
congvu 0:24041b847eb5 354
congvu 0:24041b847eb5 355 // read until start byte (0xFF)
congvu 0:24041b847eb5 356 while (_spi.write(0xFF) != 0xFE);
congvu 0:24041b847eb5 357
congvu 0:24041b847eb5 358 // read data
congvu 0:24041b847eb5 359 for (int i = 0; i < length; i++) {
congvu 0:24041b847eb5 360 buffer[i] = _spi.write(0xFF);
congvu 0:24041b847eb5 361 }
congvu 0:24041b847eb5 362 _spi.write(0xFF); // checksum
congvu 0:24041b847eb5 363 _spi.write(0xFF);
congvu 0:24041b847eb5 364
congvu 0:24041b847eb5 365 _cs = 1;
congvu 0:24041b847eb5 366 _spi.write(0xFF);
congvu 0:24041b847eb5 367 return 0;
congvu 0:24041b847eb5 368 }
congvu 0:24041b847eb5 369
congvu 0:24041b847eb5 370 int SDFileSystem::_write(const uint8_t*buffer, uint32_t length) {
congvu 0:24041b847eb5 371 _cs = 0;
congvu 0:24041b847eb5 372
congvu 0:24041b847eb5 373 // indicate start of block
congvu 0:24041b847eb5 374 _spi.write(0xFE);
congvu 0:24041b847eb5 375
congvu 0:24041b847eb5 376 // write the data
congvu 0:24041b847eb5 377 for (int i = 0; i < length; i++) {
congvu 0:24041b847eb5 378 _spi.write(buffer[i]);
congvu 0:24041b847eb5 379 }
congvu 0:24041b847eb5 380
congvu 0:24041b847eb5 381 // write the checksum
congvu 0:24041b847eb5 382 _spi.write(0xFF);
congvu 0:24041b847eb5 383 _spi.write(0xFF);
congvu 0:24041b847eb5 384
congvu 0:24041b847eb5 385 // check the response token
congvu 0:24041b847eb5 386 if ((_spi.write(0xFF) & 0x1F) != 0x05) {
congvu 0:24041b847eb5 387 _cs = 1;
congvu 0:24041b847eb5 388 _spi.write(0xFF);
congvu 0:24041b847eb5 389 return 1;
congvu 0:24041b847eb5 390 }
congvu 0:24041b847eb5 391
congvu 0:24041b847eb5 392 // wait for write to finish
congvu 0:24041b847eb5 393 while (_spi.write(0xFF) == 0);
congvu 0:24041b847eb5 394
congvu 0:24041b847eb5 395 _cs = 1;
congvu 0:24041b847eb5 396 _spi.write(0xFF);
congvu 0:24041b847eb5 397 return 0;
congvu 0:24041b847eb5 398 }
congvu 0:24041b847eb5 399
congvu 0:24041b847eb5 400 static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
congvu 0:24041b847eb5 401 uint32_t bits = 0;
congvu 0:24041b847eb5 402 uint32_t size = 1 + msb - lsb;
congvu 0:24041b847eb5 403 for (int i = 0; i < size; i++) {
congvu 0:24041b847eb5 404 uint32_t position = lsb + i;
congvu 0:24041b847eb5 405 uint32_t byte = 15 - (position >> 3);
congvu 0:24041b847eb5 406 uint32_t bit = position & 0x7;
congvu 0:24041b847eb5 407 uint32_t value = (data[byte] >> bit) & 1;
congvu 0:24041b847eb5 408 bits |= value << i;
congvu 0:24041b847eb5 409 }
congvu 0:24041b847eb5 410 return bits;
congvu 0:24041b847eb5 411 }
congvu 0:24041b847eb5 412
congvu 0:24041b847eb5 413 uint64_t SDFileSystem::_sd_sectors() {
congvu 0:24041b847eb5 414 uint32_t c_size, c_size_mult, read_bl_len;
congvu 0:24041b847eb5 415 uint32_t block_len, mult, blocknr, capacity;
congvu 0:24041b847eb5 416 uint32_t hc_c_size;
congvu 0:24041b847eb5 417 uint64_t blocks;
congvu 0:24041b847eb5 418
congvu 0:24041b847eb5 419 // CMD9, Response R2 (R1 byte + 16-byte block read)
congvu 0:24041b847eb5 420 if (_cmdx(9, 0) != 0) {
congvu 0:24041b847eb5 421 debug("Didn't get a response from the disk\n");
congvu 0:24041b847eb5 422 return 0;
congvu 0:24041b847eb5 423 }
congvu 0:24041b847eb5 424
congvu 0:24041b847eb5 425 uint8_t csd[16];
congvu 0:24041b847eb5 426 if (_read(csd, 16) != 0) {
congvu 0:24041b847eb5 427 debug("Couldn't read csd response from disk\n");
congvu 0:24041b847eb5 428 return 0;
congvu 0:24041b847eb5 429 }
congvu 0:24041b847eb5 430
congvu 0:24041b847eb5 431 // csd_structure : csd[127:126]
congvu 0:24041b847eb5 432 // c_size : csd[73:62]
congvu 0:24041b847eb5 433 // c_size_mult : csd[49:47]
congvu 0:24041b847eb5 434 // read_bl_len : csd[83:80] - the *maximum* read block length
congvu 0:24041b847eb5 435
congvu 0:24041b847eb5 436 int csd_structure = ext_bits(csd, 127, 126);
congvu 0:24041b847eb5 437
congvu 0:24041b847eb5 438 switch (csd_structure) {
congvu 0:24041b847eb5 439 case 0:
congvu 0:24041b847eb5 440 cdv = 512;
congvu 0:24041b847eb5 441 c_size = ext_bits(csd, 73, 62);
congvu 0:24041b847eb5 442 c_size_mult = ext_bits(csd, 49, 47);
congvu 0:24041b847eb5 443 read_bl_len = ext_bits(csd, 83, 80);
congvu 0:24041b847eb5 444
congvu 0:24041b847eb5 445 block_len = 1 << read_bl_len;
congvu 0:24041b847eb5 446 mult = 1 << (c_size_mult + 2);
congvu 0:24041b847eb5 447 blocknr = (c_size + 1) * mult;
congvu 0:24041b847eb5 448 capacity = blocknr * block_len;
congvu 0:24041b847eb5 449 blocks = capacity / 512;
congvu 0:24041b847eb5 450 debug_if(SD_DBG, "\n\rSDCard\n\rc_size: %d \n\rcapacity: %ld \n\rsectors: %lld\n\r", c_size, capacity, blocks);
congvu 0:24041b847eb5 451 break;
congvu 0:24041b847eb5 452
congvu 0:24041b847eb5 453 case 1:
congvu 0:24041b847eb5 454 cdv = 1;
congvu 0:24041b847eb5 455 hc_c_size = ext_bits(csd, 63, 48);
congvu 0:24041b847eb5 456 blocks = (hc_c_size+1)*1024;
congvu 0:24041b847eb5 457 debug_if(SD_DBG, "\n\rSDHC Card \n\rhc_c_size: %d\n\rcapacity: %lld \n\rsectors: %lld\n\r", hc_c_size, blocks*512, blocks);
congvu 0:24041b847eb5 458 break;
congvu 0:24041b847eb5 459
congvu 0:24041b847eb5 460 default:
congvu 0:24041b847eb5 461 debug("CSD struct unsupported\r\n");
congvu 0:24041b847eb5 462 return 0;
congvu 0:24041b847eb5 463 };
congvu 0:24041b847eb5 464 return blocks;
congvu 0:24041b847eb5 465 }