Madeline Kistler / SDFileSystem2

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SDFileSystem.cpp@0:812e8b0b2832, 2020-11-17 (annotated)

Committer:
mkistler
Date:
Tue Nov 17 20:30:08 2020 +0000
Revision:
0:812e8b0b2832
Final draft.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mkistler 0:812e8b0b2832 1 /* mbed Microcontroller Library
mkistler 0:812e8b0b2832 2 * Copyright (c) 2006-2012 ARM Limited
mkistler 0:812e8b0b2832 3 *
mkistler 0:812e8b0b2832 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
mkistler 0:812e8b0b2832 5 * of this software and associated documentation files (the "Software"), to deal
mkistler 0:812e8b0b2832 6 * in the Software without restriction, including without limitation the rights
mkistler 0:812e8b0b2832 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
mkistler 0:812e8b0b2832 8 * copies of the Software, and to permit persons to whom the Software is
mkistler 0:812e8b0b2832 9 * furnished to do so, subject to the following conditions:
mkistler 0:812e8b0b2832 10 *
mkistler 0:812e8b0b2832 11 * The above copyright notice and this permission notice shall be included in
mkistler 0:812e8b0b2832 12 * all copies or substantial portions of the Software.
mkistler 0:812e8b0b2832 13 *
mkistler 0:812e8b0b2832 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
mkistler 0:812e8b0b2832 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
mkistler 0:812e8b0b2832 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
mkistler 0:812e8b0b2832 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
mkistler 0:812e8b0b2832 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
mkistler 0:812e8b0b2832 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
mkistler 0:812e8b0b2832 20 * SOFTWARE.
mkistler 0:812e8b0b2832 21 */
mkistler 0:812e8b0b2832 22 /* Introduction
mkistler 0:812e8b0b2832 23 * ------------
mkistler 0:812e8b0b2832 24 * SD and MMC cards support a number of interfaces, but common to them all
mkistler 0:812e8b0b2832 25 * is one based on SPI. This is the one I'm implmenting because it means
mkistler 0:812e8b0b2832 26 * it is much more portable even though not so performant, and we already
mkistler 0:812e8b0b2832 27 * have the mbed SPI Interface!
mkistler 0:812e8b0b2832 28 *
mkistler 0:812e8b0b2832 29 * The main reference I'm using is Chapter 7, "SPI Mode" of:
mkistler 0:812e8b0b2832 30 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
mkistler 0:812e8b0b2832 31 *
mkistler 0:812e8b0b2832 32 * SPI Startup
mkistler 0:812e8b0b2832 33 * -----------
mkistler 0:812e8b0b2832 34 * The SD card powers up in SD mode. The SPI interface mode is selected by
mkistler 0:812e8b0b2832 35 * asserting CS low and sending the reset command (CMD0). The card will
mkistler 0:812e8b0b2832 36 * respond with a (R1) response.
mkistler 0:812e8b0b2832 37 *
mkistler 0:812e8b0b2832 38 * CMD8 is optionally sent to determine the voltage range supported, and
mkistler 0:812e8b0b2832 39 * indirectly determine whether it is a version 1.x SD/non-SD card or
mkistler 0:812e8b0b2832 40 * version 2.x. I'll just ignore this for now.
mkistler 0:812e8b0b2832 41 *
mkistler 0:812e8b0b2832 42 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
mkistler 0:812e8b0b2832 43 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
mkistler 0:812e8b0b2832 44 *
mkistler 0:812e8b0b2832 45 * You should also indicate whether the host supports High Capicity cards,
mkistler 0:812e8b0b2832 46 * and check whether the card is high capacity - i'll also ignore this
mkistler 0:812e8b0b2832 47 *
mkistler 0:812e8b0b2832 48 * SPI Protocol
mkistler 0:812e8b0b2832 49 * ------------
mkistler 0:812e8b0b2832 50 * The SD SPI protocol is based on transactions made up of 8-bit words, with
mkistler 0:812e8b0b2832 51 * the host starting every bus transaction by asserting the CS signal low. The
mkistler 0:812e8b0b2832 52 * card always responds to commands, data blocks and errors.
mkistler 0:812e8b0b2832 53 *
mkistler 0:812e8b0b2832 54 * The protocol supports a CRC, but by default it is off (except for the
mkistler 0:812e8b0b2832 55 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
mkistler 0:812e8b0b2832 56 * I'll leave the CRC off I think!
mkistler 0:812e8b0b2832 57 *
mkistler 0:812e8b0b2832 58 * Standard capacity cards have variable data block sizes, whereas High
mkistler 0:812e8b0b2832 59 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
mkistler 0:812e8b0b2832 60 * just always use the Standard Capacity cards with a block size of 512 bytes.
mkistler 0:812e8b0b2832 61 * This is set with CMD16.
mkistler 0:812e8b0b2832 62 *
mkistler 0:812e8b0b2832 63 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
mkistler 0:812e8b0b2832 64 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
mkistler 0:812e8b0b2832 65 * the card gets a read command, it responds with a response token, and then
mkistler 0:812e8b0b2832 66 * a data token or an error.
mkistler 0:812e8b0b2832 67 *
mkistler 0:812e8b0b2832 68 * SPI Command Format
mkistler 0:812e8b0b2832 69 * ------------------
mkistler 0:812e8b0b2832 70 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
mkistler 0:812e8b0b2832 71 *
mkistler 0:812e8b0b2832 72 * +---------------+------------+------------+-----------+----------+--------------+
mkistler 0:812e8b0b2832 73 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
mkistler 0:812e8b0b2832 74 * +---------------+------------+------------+-----------+----------+--------------+
mkistler 0:812e8b0b2832 75 *
mkistler 0:812e8b0b2832 76 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
mkistler 0:812e8b0b2832 77 *
mkistler 0:812e8b0b2832 78 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
mkistler 0:812e8b0b2832 79 *
mkistler 0:812e8b0b2832 80 * SPI Response Format
mkistler 0:812e8b0b2832 81 * -------------------
mkistler 0:812e8b0b2832 82 * The main response format (R1) is a status byte (normally zero). Key flags:
mkistler 0:812e8b0b2832 83 * idle - 1 if the card is in an idle state/initialising
mkistler 0:812e8b0b2832 84 * cmd - 1 if an illegal command code was detected
mkistler 0:812e8b0b2832 85 *
mkistler 0:812e8b0b2832 86 * +-------------------------------------------------+
mkistler 0:812e8b0b2832 87 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
mkistler 0:812e8b0b2832 88 * +-------------------------------------------------+
mkistler 0:812e8b0b2832 89 *
mkistler 0:812e8b0b2832 90 * R1b is the same, except it is followed by a busy signal (zeros) until
mkistler 0:812e8b0b2832 91 * the first non-zero byte when it is ready again.
mkistler 0:812e8b0b2832 92 *
mkistler 0:812e8b0b2832 93 * Data Response Token
mkistler 0:812e8b0b2832 94 * -------------------
mkistler 0:812e8b0b2832 95 * Every data block written to the card is acknowledged by a byte
mkistler 0:812e8b0b2832 96 * response token
mkistler 0:812e8b0b2832 97 *
mkistler 0:812e8b0b2832 98 * +----------------------+
mkistler 0:812e8b0b2832 99 * | xxx | 0 | status | 1 |
mkistler 0:812e8b0b2832 100 * +----------------------+
mkistler 0:812e8b0b2832 101 * 010 - OK!
mkistler 0:812e8b0b2832 102 * 101 - CRC Error
mkistler 0:812e8b0b2832 103 * 110 - Write Error
mkistler 0:812e8b0b2832 104 *
mkistler 0:812e8b0b2832 105 * Single Block Read and Write
mkistler 0:812e8b0b2832 106 * ---------------------------
mkistler 0:812e8b0b2832 107 *
mkistler 0:812e8b0b2832 108 * Block transfers have a byte header, followed by the data, followed
mkistler 0:812e8b0b2832 109 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
mkistler 0:812e8b0b2832 110 *
mkistler 0:812e8b0b2832 111 * +------+---------+---------+- - - -+---------+-----------+----------+
mkistler 0:812e8b0b2832 112 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
mkistler 0:812e8b0b2832 113 * +------+---------+---------+- - - -+---------+-----------+----------+
mkistler 0:812e8b0b2832 114 */
mkistler 0:812e8b0b2832 115 #include "SDFileSystem.h"
mkistler 0:812e8b0b2832 116 #include "mbed_debug.h"
mkistler 0:812e8b0b2832 117
mkistler 0:812e8b0b2832 118 #define SD_COMMAND_TIMEOUT 5000
mkistler 0:812e8b0b2832 119
mkistler 0:812e8b0b2832 120 #define SD_DBG 0
mkistler 0:812e8b0b2832 121
mkistler 0:812e8b0b2832 122 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
mkistler 0:812e8b0b2832 123 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs), _is_initialized(0) {
mkistler 0:812e8b0b2832 124 _cs = 1;
mkistler 0:812e8b0b2832 125
mkistler 0:812e8b0b2832 126 // Set default to 100kHz for initialisation and 1MHz for data transfer
mkistler 0:812e8b0b2832 127 _init_sck = 100000;
mkistler 0:812e8b0b2832 128 _transfer_sck = 1000000;
mkistler 0:812e8b0b2832 129 }
mkistler 0:812e8b0b2832 130
mkistler 0:812e8b0b2832 131 #define R1_IDLE_STATE (1 << 0)
mkistler 0:812e8b0b2832 132 #define R1_ERASE_RESET (1 << 1)
mkistler 0:812e8b0b2832 133 #define R1_ILLEGAL_COMMAND (1 << 2)
mkistler 0:812e8b0b2832 134 #define R1_COM_CRC_ERROR (1 << 3)
mkistler 0:812e8b0b2832 135 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
mkistler 0:812e8b0b2832 136 #define R1_ADDRESS_ERROR (1 << 5)
mkistler 0:812e8b0b2832 137 #define R1_PARAMETER_ERROR (1 << 6)
mkistler 0:812e8b0b2832 138
mkistler 0:812e8b0b2832 139 // Types
mkistler 0:812e8b0b2832 140 // - v1.x Standard Capacity
mkistler 0:812e8b0b2832 141 // - v2.x Standard Capacity
mkistler 0:812e8b0b2832 142 // - v2.x High Capacity
mkistler 0:812e8b0b2832 143 // - Not recognised as an SD Card
mkistler 0:812e8b0b2832 144 #define SDCARD_FAIL 0
mkistler 0:812e8b0b2832 145 #define SDCARD_V1 1
mkistler 0:812e8b0b2832 146 #define SDCARD_V2 2
mkistler 0:812e8b0b2832 147 #define SDCARD_V2HC 3
mkistler 0:812e8b0b2832 148
mkistler 0:812e8b0b2832 149 int SDFileSystem::initialise_card() {
mkistler 0:812e8b0b2832 150 // Set to SCK for initialisation, and clock card with cs = 1
mkistler 0:812e8b0b2832 151 _spi.frequency(_init_sck);
mkistler 0:812e8b0b2832 152 _cs = 1;
mkistler 0:812e8b0b2832 153 for (int i = 0; i < 16; i++) {
mkistler 0:812e8b0b2832 154 _spi.write(0xFF);
mkistler 0:812e8b0b2832 155 }
mkistler 0:812e8b0b2832 156
mkistler 0:812e8b0b2832 157 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
mkistler 0:812e8b0b2832 158 if (_cmd(0, 0) != R1_IDLE_STATE) {
mkistler 0:812e8b0b2832 159 debug("No disk, or could not put SD card in to SPI idle state\n");
mkistler 0:812e8b0b2832 160 return SDCARD_FAIL;
mkistler 0:812e8b0b2832 161 }
mkistler 0:812e8b0b2832 162
mkistler 0:812e8b0b2832 163 // send CMD8 to determine whther it is ver 2.x
mkistler 0:812e8b0b2832 164 int r = _cmd8();
mkistler 0:812e8b0b2832 165 if (r == R1_IDLE_STATE) {
mkistler 0:812e8b0b2832 166 return initialise_card_v2();
mkistler 0:812e8b0b2832 167 } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
mkistler 0:812e8b0b2832 168 return initialise_card_v1();
mkistler 0:812e8b0b2832 169 } else {
mkistler 0:812e8b0b2832 170 debug("Not in idle state after sending CMD8 (not an SD card?)\n");
mkistler 0:812e8b0b2832 171 return SDCARD_FAIL;
mkistler 0:812e8b0b2832 172 }
mkistler 0:812e8b0b2832 173 }
mkistler 0:812e8b0b2832 174
mkistler 0:812e8b0b2832 175 int SDFileSystem::initialise_card_v1() {
mkistler 0:812e8b0b2832 176 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
mkistler 0:812e8b0b2832 177 _cmd(55, 0);
mkistler 0:812e8b0b2832 178 if (_cmd(41, 0) == 0) {
mkistler 0:812e8b0b2832 179 cdv = 512;
mkistler 0:812e8b0b2832 180 debug_if(SD_DBG, "\n\rInit: SEDCARD_V1\n\r");
mkistler 0:812e8b0b2832 181 return SDCARD_V1;
mkistler 0:812e8b0b2832 182 }
mkistler 0:812e8b0b2832 183 }
mkistler 0:812e8b0b2832 184
mkistler 0:812e8b0b2832 185 debug("Timeout waiting for v1.x card\n");
mkistler 0:812e8b0b2832 186 return SDCARD_FAIL;
mkistler 0:812e8b0b2832 187 }
mkistler 0:812e8b0b2832 188
mkistler 0:812e8b0b2832 189 int SDFileSystem::initialise_card_v2() {
mkistler 0:812e8b0b2832 190 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
mkistler 0:812e8b0b2832 191 wait_ms(50);
mkistler 0:812e8b0b2832 192 _cmd58();
mkistler 0:812e8b0b2832 193 _cmd(55, 0);
mkistler 0:812e8b0b2832 194 if (_cmd(41, 0x40000000) == 0) {
mkistler 0:812e8b0b2832 195 _cmd58();
mkistler 0:812e8b0b2832 196 debug_if(SD_DBG, "\n\rInit: SDCARD_V2\n\r");
mkistler 0:812e8b0b2832 197 cdv = 1;
mkistler 0:812e8b0b2832 198 return SDCARD_V2;
mkistler 0:812e8b0b2832 199 }
mkistler 0:812e8b0b2832 200 }
mkistler 0:812e8b0b2832 201
mkistler 0:812e8b0b2832 202 debug("Timeout waiting for v2.x card\n");
mkistler 0:812e8b0b2832 203 return SDCARD_FAIL;
mkistler 0:812e8b0b2832 204 }
mkistler 0:812e8b0b2832 205
mkistler 0:812e8b0b2832 206 int SDFileSystem::disk_initialize() {
mkistler 0:812e8b0b2832 207 _is_initialized = initialise_card();
mkistler 0:812e8b0b2832 208 if (_is_initialized == 0) {
mkistler 0:812e8b0b2832 209 debug("Fail to initialize card\n");
mkistler 0:812e8b0b2832 210 return 1;
mkistler 0:812e8b0b2832 211 }
mkistler 0:812e8b0b2832 212 debug_if(SD_DBG, "init card = %d\n", _is_initialized);
mkistler 0:812e8b0b2832 213 _sectors = _sd_sectors();
mkistler 0:812e8b0b2832 214
mkistler 0:812e8b0b2832 215 // Set block length to 512 (CMD16)
mkistler 0:812e8b0b2832 216 if (_cmd(16, 512) != 0) {
mkistler 0:812e8b0b2832 217 debug("Set 512-byte block timed out\n");
mkistler 0:812e8b0b2832 218 return 1;
mkistler 0:812e8b0b2832 219 }
mkistler 0:812e8b0b2832 220
mkistler 0:812e8b0b2832 221 // Set SCK for data transfer
mkistler 0:812e8b0b2832 222 _spi.frequency(_transfer_sck);
mkistler 0:812e8b0b2832 223 return 0;
mkistler 0:812e8b0b2832 224 }
mkistler 0:812e8b0b2832 225
mkistler 0:812e8b0b2832 226 int SDFileSystem::disk_write(const uint8_t* buffer, uint32_t block_number, uint32_t count) {
mkistler 0:812e8b0b2832 227 if (!_is_initialized) {
mkistler 0:812e8b0b2832 228 return -1;
mkistler 0:812e8b0b2832 229 }
mkistler 0:812e8b0b2832 230
mkistler 0:812e8b0b2832 231 for (uint32_t b = block_number; b < block_number + count; b++) {
mkistler 0:812e8b0b2832 232 // set write address for single block (CMD24)
mkistler 0:812e8b0b2832 233 if (_cmd(24, b * cdv) != 0) {
mkistler 0:812e8b0b2832 234 return 1;
mkistler 0:812e8b0b2832 235 }
mkistler 0:812e8b0b2832 236
mkistler 0:812e8b0b2832 237 // send the data block
mkistler 0:812e8b0b2832 238 _write(buffer, 512);
mkistler 0:812e8b0b2832 239 buffer += 512;
mkistler 0:812e8b0b2832 240 }
mkistler 0:812e8b0b2832 241
mkistler 0:812e8b0b2832 242 return 0;
mkistler 0:812e8b0b2832 243 }
mkistler 0:812e8b0b2832 244
mkistler 0:812e8b0b2832 245 int SDFileSystem::disk_read(uint8_t* buffer, uint32_t block_number, uint32_t count) {
mkistler 0:812e8b0b2832 246 if (!_is_initialized) {
mkistler 0:812e8b0b2832 247 return -1;
mkistler 0:812e8b0b2832 248 }
mkistler 0:812e8b0b2832 249
mkistler 0:812e8b0b2832 250 for (uint32_t b = block_number; b < block_number + count; b++) {
mkistler 0:812e8b0b2832 251 // set read address for single block (CMD17)
mkistler 0:812e8b0b2832 252 if (_cmd(17, b * cdv) != 0) {
mkistler 0:812e8b0b2832 253 return 1;
mkistler 0:812e8b0b2832 254 }
mkistler 0:812e8b0b2832 255
mkistler 0:812e8b0b2832 256 // receive the data
mkistler 0:812e8b0b2832 257 _read(buffer, 512);
mkistler 0:812e8b0b2832 258 buffer += 512;
mkistler 0:812e8b0b2832 259 }
mkistler 0:812e8b0b2832 260
mkistler 0:812e8b0b2832 261 return 0;
mkistler 0:812e8b0b2832 262 }
mkistler 0:812e8b0b2832 263
mkistler 0:812e8b0b2832 264 int SDFileSystem::disk_status() {
mkistler 0:812e8b0b2832 265 // FATFileSystem::disk_status() returns 0 when initialized
mkistler 0:812e8b0b2832 266 if (_is_initialized) {
mkistler 0:812e8b0b2832 267 return 0;
mkistler 0:812e8b0b2832 268 } else {
mkistler 0:812e8b0b2832 269 return 1;
mkistler 0:812e8b0b2832 270 }
mkistler 0:812e8b0b2832 271 }
mkistler 0:812e8b0b2832 272
mkistler 0:812e8b0b2832 273 int SDFileSystem::disk_sync() { return 0; }
mkistler 0:812e8b0b2832 274 uint32_t SDFileSystem::disk_sectors() { return _sectors; }
mkistler 0:812e8b0b2832 275
mkistler 0:812e8b0b2832 276
mkistler 0:812e8b0b2832 277 // PRIVATE FUNCTIONS
mkistler 0:812e8b0b2832 278 int SDFileSystem::_cmd(int cmd, int arg) {
mkistler 0:812e8b0b2832 279 _cs = 0;
mkistler 0:812e8b0b2832 280
mkistler 0:812e8b0b2832 281 // send a command
mkistler 0:812e8b0b2832 282 _spi.write(0x40 | cmd);
mkistler 0:812e8b0b2832 283 _spi.write(arg >> 24);
mkistler 0:812e8b0b2832 284 _spi.write(arg >> 16);
mkistler 0:812e8b0b2832 285 _spi.write(arg >> 8);
mkistler 0:812e8b0b2832 286 _spi.write(arg >> 0);
mkistler 0:812e8b0b2832 287 _spi.write(0x95);
mkistler 0:812e8b0b2832 288
mkistler 0:812e8b0b2832 289 // wait for the repsonse (response[7] == 0)
mkistler 0:812e8b0b2832 290 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
mkistler 0:812e8b0b2832 291 int response = _spi.write(0xFF);
mkistler 0:812e8b0b2832 292 if (!(response & 0x80)) {
mkistler 0:812e8b0b2832 293 _cs = 1;
mkistler 0:812e8b0b2832 294 _spi.write(0xFF);
mkistler 0:812e8b0b2832 295 return response;
mkistler 0:812e8b0b2832 296 }
mkistler 0:812e8b0b2832 297 }
mkistler 0:812e8b0b2832 298 _cs = 1;
mkistler 0:812e8b0b2832 299 _spi.write(0xFF);
mkistler 0:812e8b0b2832 300 return -1; // timeout
mkistler 0:812e8b0b2832 301 }
mkistler 0:812e8b0b2832 302 int SDFileSystem::_cmdx(int cmd, int arg) {
mkistler 0:812e8b0b2832 303 _cs = 0;
mkistler 0:812e8b0b2832 304
mkistler 0:812e8b0b2832 305 // send a command
mkistler 0:812e8b0b2832 306 _spi.write(0x40 | cmd);
mkistler 0:812e8b0b2832 307 _spi.write(arg >> 24);
mkistler 0:812e8b0b2832 308 _spi.write(arg >> 16);
mkistler 0:812e8b0b2832 309 _spi.write(arg >> 8);
mkistler 0:812e8b0b2832 310 _spi.write(arg >> 0);
mkistler 0:812e8b0b2832 311 _spi.write(0x95);
mkistler 0:812e8b0b2832 312
mkistler 0:812e8b0b2832 313 // wait for the repsonse (response[7] == 0)
mkistler 0:812e8b0b2832 314 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
mkistler 0:812e8b0b2832 315 int response = _spi.write(0xFF);
mkistler 0:812e8b0b2832 316 if (!(response & 0x80)) {
mkistler 0:812e8b0b2832 317 return response;
mkistler 0:812e8b0b2832 318 }
mkistler 0:812e8b0b2832 319 }
mkistler 0:812e8b0b2832 320 _cs = 1;
mkistler 0:812e8b0b2832 321 _spi.write(0xFF);
mkistler 0:812e8b0b2832 322 return -1; // timeout
mkistler 0:812e8b0b2832 323 }
mkistler 0:812e8b0b2832 324
mkistler 0:812e8b0b2832 325
mkistler 0:812e8b0b2832 326 int SDFileSystem::_cmd58() {
mkistler 0:812e8b0b2832 327 _cs = 0;
mkistler 0:812e8b0b2832 328 int arg = 0;
mkistler 0:812e8b0b2832 329
mkistler 0:812e8b0b2832 330 // send a command
mkistler 0:812e8b0b2832 331 _spi.write(0x40 | 58);
mkistler 0:812e8b0b2832 332 _spi.write(arg >> 24);
mkistler 0:812e8b0b2832 333 _spi.write(arg >> 16);
mkistler 0:812e8b0b2832 334 _spi.write(arg >> 8);
mkistler 0:812e8b0b2832 335 _spi.write(arg >> 0);
mkistler 0:812e8b0b2832 336 _spi.write(0x95);
mkistler 0:812e8b0b2832 337
mkistler 0:812e8b0b2832 338 // wait for the repsonse (response[7] == 0)
mkistler 0:812e8b0b2832 339 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
mkistler 0:812e8b0b2832 340 int response = _spi.write(0xFF);
mkistler 0:812e8b0b2832 341 if (!(response & 0x80)) {
mkistler 0:812e8b0b2832 342 int ocr = _spi.write(0xFF) << 24;
mkistler 0:812e8b0b2832 343 ocr |= _spi.write(0xFF) << 16;
mkistler 0:812e8b0b2832 344 ocr |= _spi.write(0xFF) << 8;
mkistler 0:812e8b0b2832 345 ocr |= _spi.write(0xFF) << 0;
mkistler 0:812e8b0b2832 346 _cs = 1;
mkistler 0:812e8b0b2832 347 _spi.write(0xFF);
mkistler 0:812e8b0b2832 348 return response;
mkistler 0:812e8b0b2832 349 }
mkistler 0:812e8b0b2832 350 }
mkistler 0:812e8b0b2832 351 _cs = 1;
mkistler 0:812e8b0b2832 352 _spi.write(0xFF);
mkistler 0:812e8b0b2832 353 return -1; // timeout
mkistler 0:812e8b0b2832 354 }
mkistler 0:812e8b0b2832 355
mkistler 0:812e8b0b2832 356 int SDFileSystem::_cmd8() {
mkistler 0:812e8b0b2832 357 _cs = 0;
mkistler 0:812e8b0b2832 358
mkistler 0:812e8b0b2832 359 // send a command
mkistler 0:812e8b0b2832 360 _spi.write(0x40 | 8); // CMD8
mkistler 0:812e8b0b2832 361 _spi.write(0x00); // reserved
mkistler 0:812e8b0b2832 362 _spi.write(0x00); // reserved
mkistler 0:812e8b0b2832 363 _spi.write(0x01); // 3.3v
mkistler 0:812e8b0b2832 364 _spi.write(0xAA); // check pattern
mkistler 0:812e8b0b2832 365 _spi.write(0x87); // crc
mkistler 0:812e8b0b2832 366
mkistler 0:812e8b0b2832 367 // wait for the repsonse (response[7] == 0)
mkistler 0:812e8b0b2832 368 for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
mkistler 0:812e8b0b2832 369 char response[5];
mkistler 0:812e8b0b2832 370 response[0] = _spi.write(0xFF);
mkistler 0:812e8b0b2832 371 if (!(response[0] & 0x80)) {
mkistler 0:812e8b0b2832 372 for (int j = 1; j < 5; j++) {
mkistler 0:812e8b0b2832 373 response[i] = _spi.write(0xFF);
mkistler 0:812e8b0b2832 374 }
mkistler 0:812e8b0b2832 375 _cs = 1;
mkistler 0:812e8b0b2832 376 _spi.write(0xFF);
mkistler 0:812e8b0b2832 377 return response[0];
mkistler 0:812e8b0b2832 378 }
mkistler 0:812e8b0b2832 379 }
mkistler 0:812e8b0b2832 380 _cs = 1;
mkistler 0:812e8b0b2832 381 _spi.write(0xFF);
mkistler 0:812e8b0b2832 382 return -1; // timeout
mkistler 0:812e8b0b2832 383 }
mkistler 0:812e8b0b2832 384
mkistler 0:812e8b0b2832 385 int SDFileSystem::_read(uint8_t *buffer, uint32_t length) {
mkistler 0:812e8b0b2832 386 _cs = 0;
mkistler 0:812e8b0b2832 387
mkistler 0:812e8b0b2832 388 // read until start byte (0xFF)
mkistler 0:812e8b0b2832 389 while (_spi.write(0xFF) != 0xFE);
mkistler 0:812e8b0b2832 390
mkistler 0:812e8b0b2832 391 // read data
mkistler 0:812e8b0b2832 392 for (uint32_t i = 0; i < length; i++) {
mkistler 0:812e8b0b2832 393 buffer[i] = _spi.write(0xFF);
mkistler 0:812e8b0b2832 394 }
mkistler 0:812e8b0b2832 395 _spi.write(0xFF); // checksum
mkistler 0:812e8b0b2832 396 _spi.write(0xFF);
mkistler 0:812e8b0b2832 397
mkistler 0:812e8b0b2832 398 _cs = 1;
mkistler 0:812e8b0b2832 399 _spi.write(0xFF);
mkistler 0:812e8b0b2832 400 return 0;
mkistler 0:812e8b0b2832 401 }
mkistler 0:812e8b0b2832 402
mkistler 0:812e8b0b2832 403 int SDFileSystem::_write(const uint8_t*buffer, uint32_t length) {
mkistler 0:812e8b0b2832 404 _cs = 0;
mkistler 0:812e8b0b2832 405
mkistler 0:812e8b0b2832 406 // indicate start of block
mkistler 0:812e8b0b2832 407 _spi.write(0xFE);
mkistler 0:812e8b0b2832 408
mkistler 0:812e8b0b2832 409 // write the data
mkistler 0:812e8b0b2832 410 for (uint32_t i = 0; i < length; i++) {
mkistler 0:812e8b0b2832 411 _spi.write(buffer[i]);
mkistler 0:812e8b0b2832 412 }
mkistler 0:812e8b0b2832 413
mkistler 0:812e8b0b2832 414 // write the checksum
mkistler 0:812e8b0b2832 415 _spi.write(0xFF);
mkistler 0:812e8b0b2832 416 _spi.write(0xFF);
mkistler 0:812e8b0b2832 417
mkistler 0:812e8b0b2832 418 // check the response token
mkistler 0:812e8b0b2832 419 if ((_spi.write(0xFF) & 0x1F) != 0x05) {
mkistler 0:812e8b0b2832 420 _cs = 1;
mkistler 0:812e8b0b2832 421 _spi.write(0xFF);
mkistler 0:812e8b0b2832 422 return 1;
mkistler 0:812e8b0b2832 423 }
mkistler 0:812e8b0b2832 424
mkistler 0:812e8b0b2832 425 // wait for write to finish
mkistler 0:812e8b0b2832 426 while (_spi.write(0xFF) == 0);
mkistler 0:812e8b0b2832 427
mkistler 0:812e8b0b2832 428 _cs = 1;
mkistler 0:812e8b0b2832 429 _spi.write(0xFF);
mkistler 0:812e8b0b2832 430 return 0;
mkistler 0:812e8b0b2832 431 }
mkistler 0:812e8b0b2832 432
mkistler 0:812e8b0b2832 433 static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
mkistler 0:812e8b0b2832 434 uint32_t bits = 0;
mkistler 0:812e8b0b2832 435 uint32_t size = 1 + msb - lsb;
mkistler 0:812e8b0b2832 436 for (uint32_t i = 0; i < size; i++) {
mkistler 0:812e8b0b2832 437 uint32_t position = lsb + i;
mkistler 0:812e8b0b2832 438 uint32_t byte = 15 - (position >> 3);
mkistler 0:812e8b0b2832 439 uint32_t bit = position & 0x7;
mkistler 0:812e8b0b2832 440 uint32_t value = (data[byte] >> bit) & 1;
mkistler 0:812e8b0b2832 441 bits |= value << i;
mkistler 0:812e8b0b2832 442 }
mkistler 0:812e8b0b2832 443 return bits;
mkistler 0:812e8b0b2832 444 }
mkistler 0:812e8b0b2832 445
mkistler 0:812e8b0b2832 446 uint32_t SDFileSystem::_sd_sectors() {
mkistler 0:812e8b0b2832 447 uint32_t c_size, c_size_mult, read_bl_len;
mkistler 0:812e8b0b2832 448 uint32_t block_len, mult, blocknr, capacity;
mkistler 0:812e8b0b2832 449 uint32_t hc_c_size;
mkistler 0:812e8b0b2832 450 uint32_t blocks;
mkistler 0:812e8b0b2832 451
mkistler 0:812e8b0b2832 452 // CMD9, Response R2 (R1 byte + 16-byte block read)
mkistler 0:812e8b0b2832 453 if (_cmdx(9, 0) != 0) {
mkistler 0:812e8b0b2832 454 debug("Didn't get a response from the disk\n");
mkistler 0:812e8b0b2832 455 return 0;
mkistler 0:812e8b0b2832 456 }
mkistler 0:812e8b0b2832 457
mkistler 0:812e8b0b2832 458 uint8_t csd[16];
mkistler 0:812e8b0b2832 459 if (_read(csd, 16) != 0) {
mkistler 0:812e8b0b2832 460 debug("Couldn't read csd response from disk\n");
mkistler 0:812e8b0b2832 461 return 0;
mkistler 0:812e8b0b2832 462 }
mkistler 0:812e8b0b2832 463
mkistler 0:812e8b0b2832 464 // csd_structure : csd[127:126]
mkistler 0:812e8b0b2832 465 // c_size : csd[73:62]
mkistler 0:812e8b0b2832 466 // c_size_mult : csd[49:47]
mkistler 0:812e8b0b2832 467 // read_bl_len : csd[83:80] - the *maximum* read block length
mkistler 0:812e8b0b2832 468
mkistler 0:812e8b0b2832 469 int csd_structure = ext_bits(csd, 127, 126);
mkistler 0:812e8b0b2832 470
mkistler 0:812e8b0b2832 471 switch (csd_structure) {
mkistler 0:812e8b0b2832 472 case 0:
mkistler 0:812e8b0b2832 473 cdv = 512;
mkistler 0:812e8b0b2832 474 c_size = ext_bits(csd, 73, 62);
mkistler 0:812e8b0b2832 475 c_size_mult = ext_bits(csd, 49, 47);
mkistler 0:812e8b0b2832 476 read_bl_len = ext_bits(csd, 83, 80);
mkistler 0:812e8b0b2832 477
mkistler 0:812e8b0b2832 478 block_len = 1 << read_bl_len;
mkistler 0:812e8b0b2832 479 mult = 1 << (c_size_mult + 2);
mkistler 0:812e8b0b2832 480 blocknr = (c_size + 1) * mult;
mkistler 0:812e8b0b2832 481 capacity = blocknr * block_len;
mkistler 0:812e8b0b2832 482 blocks = capacity / 512;
mkistler 0:812e8b0b2832 483 debug_if(SD_DBG, "\n\rSDCard\n\rc_size: %d \n\rcapacity: %ld \n\rsectors: %lld\n\r", c_size, capacity, blocks);
mkistler 0:812e8b0b2832 484 break;
mkistler 0:812e8b0b2832 485
mkistler 0:812e8b0b2832 486 case 1:
mkistler 0:812e8b0b2832 487 cdv = 1;
mkistler 0:812e8b0b2832 488 hc_c_size = ext_bits(csd, 63, 48);
mkistler 0:812e8b0b2832 489 blocks = (hc_c_size+1)*1024;
mkistler 0:812e8b0b2832 490 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);
mkistler 0:812e8b0b2832 491 break;
mkistler 0:812e8b0b2832 492
mkistler 0:812e8b0b2832 493 default:
mkistler 0:812e8b0b2832 494 debug("CSD struct unsupported\r\n");
mkistler 0:812e8b0b2832 495 return 0;
mkistler 0:812e8b0b2832 496 };
mkistler 0:812e8b0b2832 497 return blocks;
mkistler 0:812e8b0b2832 498 }