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Dependencies:   FATFileSystem

Fork of SDFileSystem by Chaiyaporn Boonyasathian

SDFileSystem.cpp@0:389b4c94c83b, 2016-12-02 (annotated)

Committer:
cha45689
Date:
Fri Dec 02 19:37:18 2016 +0000
Revision:
0:389b4c94c83b
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cha45689 0:389b4c94c83b 1 /* mbed Microcontroller Library
cha45689 0:389b4c94c83b 2 * Copyright (c) 2006-2012 ARM Limited
cha45689 0:389b4c94c83b 3 *
cha45689 0:389b4c94c83b 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
cha45689 0:389b4c94c83b 5 * of this software and associated documentation files (the "Software"), to deal
cha45689 0:389b4c94c83b 6 * in the Software without restriction, including without limitation the rights
cha45689 0:389b4c94c83b 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
cha45689 0:389b4c94c83b 8 * copies of the Software, and to permit persons to whom the Software is
cha45689 0:389b4c94c83b 9 * furnished to do so, subject to the following conditions:
cha45689 0:389b4c94c83b 10 *
cha45689 0:389b4c94c83b 11 * The above copyright notice and this permission notice shall be included in
cha45689 0:389b4c94c83b 12 * all copies or substantial portions of the Software.
cha45689 0:389b4c94c83b 13 *
cha45689 0:389b4c94c83b 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
cha45689 0:389b4c94c83b 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
cha45689 0:389b4c94c83b 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
cha45689 0:389b4c94c83b 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
cha45689 0:389b4c94c83b 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
cha45689 0:389b4c94c83b 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
cha45689 0:389b4c94c83b 20 * SOFTWARE.
cha45689 0:389b4c94c83b 21 */
cha45689 0:389b4c94c83b 22
cha45689 0:389b4c94c83b 23 /* Introduction
cha45689 0:389b4c94c83b 24 * ------------
cha45689 0:389b4c94c83b 25 * SD and MMC cards support a number of interfaces, but common to them all
cha45689 0:389b4c94c83b 26 * is one based on SPI. This is the one I'm implmenting because it means
cha45689 0:389b4c94c83b 27 * it is much more portable even though not so performant, and we already
cha45689 0:389b4c94c83b 28 * have the mbed SPI Interface!
cha45689 0:389b4c94c83b 29 *
cha45689 0:389b4c94c83b 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
cha45689 0:389b4c94c83b 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
cha45689 0:389b4c94c83b 32 *
cha45689 0:389b4c94c83b 33 * SPI Startup
cha45689 0:389b4c94c83b 34 * -----------
cha45689 0:389b4c94c83b 35 * The SD card powers up in SD mode. The
cha45689 0:389b4c94c83b 36
cha45689 0:389b4c94c83b 37 interface mode is selected by
cha45689 0:389b4c94c83b 38 * asserting CS low and sending the reset command (CMD0). The card will
cha45689 0:389b4c94c83b 39 * respond with a (R1) response.
cha45689 0:389b4c94c83b 40 *
cha45689 0:389b4c94c83b 41 * CMD8 is optionally sent to determine the voltage range supported, and
cha45689 0:389b4c94c83b 42 * indirectly determine whether it is a version 1.x SD/non-SD card or
cha45689 0:389b4c94c83b 43 * version 2.x. I'll just ignore this for now.
cha45689 0:389b4c94c83b 44 *
cha45689 0:389b4c94c83b 45 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
cha45689 0:389b4c94c83b 46 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
cha45689 0:389b4c94c83b 47 *
cha45689 0:389b4c94c83b 48 * You should also indicate whether the host supports High Capicity cards,
cha45689 0:389b4c94c83b 49 * and check whether the card is high capacity - i'll also ignore this
cha45689 0:389b4c94c83b 50 *
cha45689 0:389b4c94c83b 51 * SPI Protocol
cha45689 0:389b4c94c83b 52 * ------------
cha45689 0:389b4c94c83b 53 * The SD SPI protocol is based on transactions made up of 8-bit words, with
cha45689 0:389b4c94c83b 54 * the host starting every bus transaction by asserting the CS signal low. The
cha45689 0:389b4c94c83b 55 * card always responds to commands, data blocks and errors.
cha45689 0:389b4c94c83b 56 *
cha45689 0:389b4c94c83b 57 * The protocol supports a CRC, but by default it is off (except for the
cha45689 0:389b4c94c83b 58 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
cha45689 0:389b4c94c83b 59 * I'll leave the CRC off I think!
cha45689 0:389b4c94c83b 60 *
cha45689 0:389b4c94c83b 61 * Standard capacity cards have variable data block sizes, whereas High
cha45689 0:389b4c94c83b 62 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
cha45689 0:389b4c94c83b 63 * just always use the Standard Capacity cards with a block size of 512 bytes.
cha45689 0:389b4c94c83b 64 * This is set with CMD16.
cha45689 0:389b4c94c83b 65 *
cha45689 0:389b4c94c83b 66 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
cha45689 0:389b4c94c83b 67 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
cha45689 0:389b4c94c83b 68 * the card gets a read command, it responds with a response token, and then
cha45689 0:389b4c94c83b 69 * a data token or an error.
cha45689 0:389b4c94c83b 70 *
cha45689 0:389b4c94c83b 71 * SPI Command Format
cha45689 0:389b4c94c83b 72 * ------------------
cha45689 0:389b4c94c83b 73 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
cha45689 0:389b4c94c83b 74 *
cha45689 0:389b4c94c83b 75 * +---------------+------------+------------+-----------+----------+--------------+
cha45689 0:389b4c94c83b 76 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
cha45689 0:389b4c94c83b 77 * +---------------+------------+------------+-----------+----------+--------------+
cha45689 0:389b4c94c83b 78 *
cha45689 0:389b4c94c83b 79 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
cha45689 0:389b4c94c83b 80 *
cha45689 0:389b4c94c83b 81 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
cha45689 0:389b4c94c83b 82 *
cha45689 0:389b4c94c83b 83 * SPI Response Format
cha45689 0:389b4c94c83b 84 * -------------------
cha45689 0:389b4c94c83b 85 * The main response format (R1) is a status byte (normally zero). Key flags:
cha45689 0:389b4c94c83b 86 * idle - 1 if the card is in an idle state/initialising
cha45689 0:389b4c94c83b 87 * cmd - 1 if an illegal command code was detected
cha45689 0:389b4c94c83b 88 *
cha45689 0:389b4c94c83b 89 * +-------------------------------------------------+
cha45689 0:389b4c94c83b 90 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
cha45689 0:389b4c94c83b 91 * +-------------------------------------------------+
cha45689 0:389b4c94c83b 92 *
cha45689 0:389b4c94c83b 93 * R1b is the same, except it is followed by a busy signal (zeros) until
cha45689 0:389b4c94c83b 94 * the first non-zero byte when it is ready again.
cha45689 0:389b4c94c83b 95 *
cha45689 0:389b4c94c83b 96 * Data Response Token
cha45689 0:389b4c94c83b 97 * -------------------
cha45689 0:389b4c94c83b 98 * Every data block written to the card is acknowledged by a byte
cha45689 0:389b4c94c83b 99 * response token
cha45689 0:389b4c94c83b 100 *
cha45689 0:389b4c94c83b 101 * +----------------------+
cha45689 0:389b4c94c83b 102 * | xxx | 0 | status | 1 |
cha45689 0:389b4c94c83b 103 * +----------------------+
cha45689 0:389b4c94c83b 104 * 010 - OK!
cha45689 0:389b4c94c83b 105 * 101 - CRC Error
cha45689 0:389b4c94c83b 106 * 110 - Write Error
cha45689 0:389b4c94c83b 107 *
cha45689 0:389b4c94c83b 108 * Single Block Read and Write
cha45689 0:389b4c94c83b 109 * ---------------------------
cha45689 0:389b4c94c83b 110 *
cha45689 0:389b4c94c83b 111 * Block transfers have a byte header, followed by the data, followed
cha45689 0:389b4c94c83b 112 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
cha45689 0:389b4c94c83b 113 *
cha45689 0:389b4c94c83b 114 * +------+---------+---------+- - - -+---------+-----------+----------+
cha45689 0:389b4c94c83b 115 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
cha45689 0:389b4c94c83b 116 * +------+---------+---------+- - - -+---------+-----------+----------+
cha45689 0:389b4c94c83b 117 */
cha45689 0:389b4c94c83b 118 #include "SDFileSystem.h"
cha45689 0:389b4c94c83b 119 #include "mbed_debug.h"
cha45689 0:389b4c94c83b 120
cha45689 0:389b4c94c83b 121 #define SD_COMMAND_TIMEOUT 5000
cha45689 0:389b4c94c83b 122
cha45689 0:389b4c94c83b 123 #define SD_DBG 0
cha45689 0:389b4c94c83b 124
cha45689 0:389b4c94c83b 125 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
cha45689 0:389b4c94c83b 126 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
cha45689 0:389b4c94c83b 127 _cs = 1;
cha45689 0:389b4c94c83b 128 }
cha45689 0:389b4c94c83b 129
cha45689 0:389b4c94c83b 130 #define R1_IDLE_STATE (1 << 0)
cha45689 0:389b4c94c83b 131 #define R1_ERASE_RESET (1 << 1)
cha45689 0:389b4c94c83b 132 #define R1_ILLEGAL_COMMAND (1 << 2)
cha45689 0:389b4c94c83b 133 #define R1_COM_CRC_ERROR (1 << 3)
cha45689 0:389b4c94c83b 134 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
cha45689 0:389b4c94c83b 135 #define R1_ADDRESS_ERROR (1 << 5)
cha45689 0:389b4c94c83b 136 #define R1_PARAMETER_ERROR (1 << 6)
cha45689 0:389b4c94c83b 137
cha45689 0:389b4c94c83b 138 // Types
cha45689 0:389b4c94c83b 139 #define SDCARD_FAIL 0 //!< v1.x Standard Capacity
cha45689 0:389b4c94c83b 140 #define SDCARD_V1 1 //!< v2.x Standard Capacity
cha45689 0:389b4c94c83b 141 #define SDCARD_V2 2 //!< v2.x High Capacity
cha45689 0:389b4c94c83b 142 #define SDCARD_V2HC 3 //!< Not recognised as an SD Card
cha45689 0:389b4c94c83b 143
cha45689 0:389b4c94c83b 144 int SDFileSystem::initialise_card() {
cha45689 0:389b4c94c83b 145 // Set to 100kHz for initialisation, and clock card with cs = 1
cha45689 0:389b4c94c83b 146 _spi.frequency(100000);
cha45689 0:389b4c94c83b 147 _cs = 1;
cha45689 0:389b4c94c83b 148 for (int i = 0; i < 16; i++) {
cha45689 0:389b4c94c83b 149 _spi.write(0xFF);
cha45689 0:389b4c94c83b 150 }
cha45689 0:389b4c94c83b 151
cha45689 0:389b4c94c83b 152 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
cha45689 0:389b4c94c83b 153 if (_cmd(0, 0) != R1_IDLE_STATE) {
cha45689 0:389b4c94c83b 154 debug("No disk, or could not put SD card in to SPI idle state\n");
cha45689 0:389b4c94c83b 155 return SDCARD_FAIL;
cha45689 0:389b4c94c83b 156 }
cha45689 0:389b4c94c83b 157
cha45689 0:389b4c94c83b 158 // send CMD8 to determine whther it is ver 2.x
cha45689 0:389b4c94c83b 159 int r = _cmd8();
cha45689 0:389b4c94c83b 160 if (r == R1_IDLE_STATE) {
cha45689 0:389b4c94c83b 161 return initialise_card_v2();
cha45689 0:389b4c94c83b 162 } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
cha45689 0:389b4c94c83b 163 return initialise_card_v1();
cha45689 0:389b4c94c83b 164 } else {
cha45689 0:389b4c94c83b 165 debug("Not in idle state after sending CMD8 (not an SD card?)\n");
cha45689 0:389b4c94c83b 166 return SDCARD_FAIL;
cha45689 0:389b4c94c83b 167 }
cha45689 0:389b4c94c83b 168 }
cha45689 0:389b4c94c83b 169
cha45689 0:389b4c94c83b 170 int SDFileSystem::initialise_card_v1() {
cha45689 0:389b4c94c83b 171 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cha45689 0:389b4c94c83b 172 _cmd(55, 0);
cha45689 0:389b4c94c83b 173 if (_cmd(41, 0) == 0) {
cha45689 0:389b4c94c83b 174 cdv = 512;
cha45689 0:389b4c94c83b 175 debug_if(SD_DBG, "\n\rInit: SEDCARD_V1\n\r");
cha45689 0:389b4c94c83b 176 return SDCARD_V1;
cha45689 0:389b4c94c83b 177 }
cha45689 0:389b4c94c83b 178 }
cha45689 0:389b4c94c83b 179
cha45689 0:389b4c94c83b 180 debug("Timeout waiting for v1.x card\n");
cha45689 0:389b4c94c83b 181 return SDCARD_FAIL;
cha45689 0:389b4c94c83b 182 }
cha45689 0:389b4c94c83b 183
cha45689 0:389b4c94c83b 184 int SDFileSystem::initialise_card_v2() {
cha45689 0:389b4c94c83b 185 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cha45689 0:389b4c94c83b 186 wait_ms(50);
cha45689 0:389b4c94c83b 187 _cmd58();
cha45689 0:389b4c94c83b 188 _cmd(55, 0);
cha45689 0:389b4c94c83b 189 if (_cmd(41, 0x40000000) == 0) {
cha45689 0:389b4c94c83b 190 _cmd58();
cha45689 0:389b4c94c83b 191 debug_if(SD_DBG, "\n\rInit: SDCARD_V2\n\r");
cha45689 0:389b4c94c83b 192 cdv = 1;
cha45689 0:389b4c94c83b 193 return SDCARD_V2;
cha45689 0:389b4c94c83b 194 }
cha45689 0:389b4c94c83b 195 }
cha45689 0:389b4c94c83b 196
cha45689 0:389b4c94c83b 197 debug("Timeout waiting for v2.x card\n");
cha45689 0:389b4c94c83b 198 return SDCARD_FAIL;
cha45689 0:389b4c94c83b 199 }
cha45689 0:389b4c94c83b 200
cha45689 0:389b4c94c83b 201 int SDFileSystem::disk_initialize() {
cha45689 0:389b4c94c83b 202 int i = initialise_card();
cha45689 0:389b4c94c83b 203 debug_if(SD_DBG, "init card = %d\n", i);
cha45689 0:389b4c94c83b 204 _sectors = _sd_sectors();
cha45689 0:389b4c94c83b 205
cha45689 0:389b4c94c83b 206 // Set block length to 512 (CMD16)
cha45689 0:389b4c94c83b 207 if (_cmd(16, 512) != 0) {
cha45689 0:389b4c94c83b 208 debug("Set 512-byte block timed out\n");
cha45689 0:389b4c94c83b 209 return 1;
cha45689 0:389b4c94c83b 210 }
cha45689 0:389b4c94c83b 211
cha45689 0:389b4c94c83b 212 _spi.frequency(12000000); // Set to 12MHz for data transfer
cha45689 0:389b4c94c83b 213 return 0;
cha45689 0:389b4c94c83b 214 }
cha45689 0:389b4c94c83b 215
cha45689 0:389b4c94c83b 216 int SDFileSystem::disk_write(const uint8_t *buffer, uint64_t block_number) {
cha45689 0:389b4c94c83b 217 // set write address for single block (CMD24)
cha45689 0:389b4c94c83b 218 if (_cmd(24, block_number * cdv) != 0) {
cha45689 0:389b4c94c83b 219 return 1;
cha45689 0:389b4c94c83b 220 }
cha45689 0:389b4c94c83b 221
cha45689 0:389b4c94c83b 222 // send the data block
cha45689 0:389b4c94c83b 223 _write(buffer, 512);
cha45689 0:389b4c94c83b 224 return 0;
cha45689 0:389b4c94c83b 225 }
cha45689 0:389b4c94c83b 226
cha45689 0:389b4c94c83b 227 int SDFileSystem::disk_read(uint8_t *buffer, uint64_t block_number) {
cha45689 0:389b4c94c83b 228 // set read address for single block (CMD17)
cha45689 0:389b4c94c83b 229 if (_cmd(17, block_number * cdv) != 0) {
cha45689 0:389b4c94c83b 230 return 1;
cha45689 0:389b4c94c83b 231 }
cha45689 0:389b4c94c83b 232
cha45689 0:389b4c94c83b 233 // receive the data
cha45689 0:389b4c94c83b 234 _read(buffer, 512);
cha45689 0:389b4c94c83b 235 return 0;
cha45689 0:389b4c94c83b 236 }
cha45689 0:389b4c94c83b 237
cha45689 0:389b4c94c83b 238 int SDFileSystem::disk_status() { return 0; }
cha45689 0:389b4c94c83b 239 int SDFileSystem::disk_sync() { return 0; }
cha45689 0:389b4c94c83b 240 uint64_t SDFileSystem::disk_sectors() { return _sectors; }
cha45689 0:389b4c94c83b 241
cha45689 0:389b4c94c83b 242
cha45689 0:389b4c94c83b 243 // PRIVATE FUNCTIONS
cha45689 0:389b4c94c83b 244 int SDFileSystem::_cmd(int cmd, int arg) {
cha45689 0:389b4c94c83b 245 _cs = 0;
cha45689 0:389b4c94c83b 246
cha45689 0:389b4c94c83b 247 // send a command
cha45689 0:389b4c94c83b 248 _spi.write(0x40 | cmd);
cha45689 0:389b4c94c83b 249 _spi.write(arg >> 24);
cha45689 0:389b4c94c83b 250 _spi.write(arg >> 16);
cha45689 0:389b4c94c83b 251 _spi.write(arg >> 8);
cha45689 0:389b4c94c83b 252 _spi.write(arg >> 0);
cha45689 0:389b4c94c83b 253 _spi.write(0x95);
cha45689 0:389b4c94c83b 254
cha45689 0:389b4c94c83b 255 // wait for the repsonse (response[7] == 0)
cha45689 0:389b4c94c83b 256 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cha45689 0:389b4c94c83b 257 int response = _spi.write(0xFF);
cha45689 0:389b4c94c83b 258 if (!(response & 0x80)) {
cha45689 0:389b4c94c83b 259 _cs = 1;
cha45689 0:389b4c94c83b 260 _spi.write(0xFF);
cha45689 0:389b4c94c83b 261 return response;
cha45689 0:389b4c94c83b 262 }
cha45689 0:389b4c94c83b 263 }
cha45689 0:389b4c94c83b 264 _cs = 1;
cha45689 0:389b4c94c83b 265 _spi.write(0xFF);
cha45689 0:389b4c94c83b 266 return -1; // timeout
cha45689 0:389b4c94c83b 267 }
cha45689 0:389b4c94c83b 268 int SDFileSystem::_cmdx(int cmd, int arg) {
cha45689 0:389b4c94c83b 269 _cs = 0;
cha45689 0:389b4c94c83b 270
cha45689 0:389b4c94c83b 271 // send a command
cha45689 0:389b4c94c83b 272 _spi.write(0x40 | cmd);
cha45689 0:389b4c94c83b 273 _spi.write(arg >> 24);
cha45689 0:389b4c94c83b 274 _spi.write(arg >> 16);
cha45689 0:389b4c94c83b 275 _spi.write(arg >> 8);
cha45689 0:389b4c94c83b 276 _spi.write(arg >> 0);
cha45689 0:389b4c94c83b 277 _spi.write(0x95);
cha45689 0:389b4c94c83b 278
cha45689 0:389b4c94c83b 279 // wait for the repsonse (response[7] == 0)
cha45689 0:389b4c94c83b 280 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cha45689 0:389b4c94c83b 281 int response = _spi.write(0xFF);
cha45689 0:389b4c94c83b 282 if (!(response & 0x80)) {
cha45689 0:389b4c94c83b 283 return response;
cha45689 0:389b4c94c83b 284 }
cha45689 0:389b4c94c83b 285 }
cha45689 0:389b4c94c83b 286 _cs = 1;
cha45689 0:389b4c94c83b 287 _spi.write(0xFF);
cha45689 0:389b4c94c83b 288 return -1; // timeout
cha45689 0:389b4c94c83b 289 }
cha45689 0:389b4c94c83b 290
cha45689 0:389b4c94c83b 291
cha45689 0:389b4c94c83b 292 int SDFileSystem::_cmd58() {
cha45689 0:389b4c94c83b 293 _cs = 0;
cha45689 0:389b4c94c83b 294 int arg = 0;
cha45689 0:389b4c94c83b 295
cha45689 0:389b4c94c83b 296 // send a command
cha45689 0:389b4c94c83b 297 _spi.write(0x40 | 58);
cha45689 0:389b4c94c83b 298 _spi.write(arg >> 24);
cha45689 0:389b4c94c83b 299 _spi.write(arg >> 16);
cha45689 0:389b4c94c83b 300 _spi.write(arg >> 8);
cha45689 0:389b4c94c83b 301 _spi.write(arg >> 0);
cha45689 0:389b4c94c83b 302 _spi.write(0x95);
cha45689 0:389b4c94c83b 303
cha45689 0:389b4c94c83b 304 // wait for the repsonse (response[7] == 0)
cha45689 0:389b4c94c83b 305 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cha45689 0:389b4c94c83b 306 int response = _spi.write(0xFF);
cha45689 0:389b4c94c83b 307 if (!(response & 0x80)) {
cha45689 0:389b4c94c83b 308 int ocr = _spi.write(0xFF) << 24;
cha45689 0:389b4c94c83b 309 ocr |= _spi.write(0xFF) << 16;
cha45689 0:389b4c94c83b 310 ocr |= _spi.write(0xFF) << 8;
cha45689 0:389b4c94c83b 311 ocr |= _spi.write(0xFF) << 0;
cha45689 0:389b4c94c83b 312 _cs = 1;
cha45689 0:389b4c94c83b 313 _spi.write(0xFF);
cha45689 0:389b4c94c83b 314 return response;
cha45689 0:389b4c94c83b 315 }
cha45689 0:389b4c94c83b 316 }
cha45689 0:389b4c94c83b 317 _cs = 1;
cha45689 0:389b4c94c83b 318 _spi.write(0xFF);
cha45689 0:389b4c94c83b 319 return -1; // timeout
cha45689 0:389b4c94c83b 320 }
cha45689 0:389b4c94c83b 321
cha45689 0:389b4c94c83b 322 int SDFileSystem::_cmd8() {
cha45689 0:389b4c94c83b 323 _cs = 0;
cha45689 0:389b4c94c83b 324
cha45689 0:389b4c94c83b 325 // send a command
cha45689 0:389b4c94c83b 326 _spi.write(0x40 | 8); // CMD8
cha45689 0:389b4c94c83b 327 _spi.write(0x00); // reserved
cha45689 0:389b4c94c83b 328 _spi.write(0x00); // reserved
cha45689 0:389b4c94c83b 329 _spi.write(0x01); // 3.3v
cha45689 0:389b4c94c83b 330 _spi.write(0xAA); // check pattern
cha45689 0:389b4c94c83b 331 _spi.write(0x87); // crc
cha45689 0:389b4c94c83b 332
cha45689 0:389b4c94c83b 333 // wait for the repsonse (response[7] == 0)
cha45689 0:389b4c94c83b 334 for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
cha45689 0:389b4c94c83b 335 char response[5];
cha45689 0:389b4c94c83b 336 response[0] = _spi.write(0xFF);
cha45689 0:389b4c94c83b 337 if (!(response[0] & 0x80)) {
cha45689 0:389b4c94c83b 338 for (int j = 1; j < 5; j++) {
cha45689 0:389b4c94c83b 339 response[i] = _spi.write(0xFF);
cha45689 0:389b4c94c83b 340 }
cha45689 0:389b4c94c83b 341 _cs = 1;
cha45689 0:389b4c94c83b 342 _spi.write(0xFF);
cha45689 0:389b4c94c83b 343 return response[0];
cha45689 0:389b4c94c83b 344 }
cha45689 0:389b4c94c83b 345 }
cha45689 0:389b4c94c83b 346 _cs = 1;
cha45689 0:389b4c94c83b 347 _spi.write(0xFF);
cha45689 0:389b4c94c83b 348 return -1; // timeout
cha45689 0:389b4c94c83b 349 }
cha45689 0:389b4c94c83b 350
cha45689 0:389b4c94c83b 351 int SDFileSystem::_read(uint8_t *buffer, uint32_t length) {
cha45689 0:389b4c94c83b 352 _cs = 0;
cha45689 0:389b4c94c83b 353
cha45689 0:389b4c94c83b 354 // read until start byte (0xFF)
cha45689 0:389b4c94c83b 355 while (_spi.write(0xFF) != 0xFE);
cha45689 0:389b4c94c83b 356
cha45689 0:389b4c94c83b 357 // read data
cha45689 0:389b4c94c83b 358 for (int i = 0; i < length; i++) {
cha45689 0:389b4c94c83b 359 buffer[i] = _spi.write(0xFF);
cha45689 0:389b4c94c83b 360 }
cha45689 0:389b4c94c83b 361 _spi.write(0xFF); // checksum
cha45689 0:389b4c94c83b 362 _spi.write(0xFF);
cha45689 0:389b4c94c83b 363
cha45689 0:389b4c94c83b 364 _cs = 1;
cha45689 0:389b4c94c83b 365 _spi.write(0xFF);
cha45689 0:389b4c94c83b 366 return 0;
cha45689 0:389b4c94c83b 367 }
cha45689 0:389b4c94c83b 368
cha45689 0:389b4c94c83b 369 int SDFileSystem::_write(const uint8_t*buffer, uint32_t length) {
cha45689 0:389b4c94c83b 370 _cs = 0;
cha45689 0:389b4c94c83b 371
cha45689 0:389b4c94c83b 372 // indicate start of block
cha45689 0:389b4c94c83b 373 _spi.write(0xFE);
cha45689 0:389b4c94c83b 374
cha45689 0:389b4c94c83b 375 // write the data
cha45689 0:389b4c94c83b 376 for (int i = 0; i < length; i++) {
cha45689 0:389b4c94c83b 377 _spi.write(buffer[i]);
cha45689 0:389b4c94c83b 378 }
cha45689 0:389b4c94c83b 379
cha45689 0:389b4c94c83b 380 // write the checksum
cha45689 0:389b4c94c83b 381 _spi.write(0xFF);
cha45689 0:389b4c94c83b 382 _spi.write(0xFF);
cha45689 0:389b4c94c83b 383
cha45689 0:389b4c94c83b 384 // check the response token
cha45689 0:389b4c94c83b 385 if ((_spi.write(0xFF) & 0x1F) != 0x05) {
cha45689 0:389b4c94c83b 386 _cs = 1;
cha45689 0:389b4c94c83b 387 _spi.write(0xFF);
cha45689 0:389b4c94c83b 388 return 1;
cha45689 0:389b4c94c83b 389 }
cha45689 0:389b4c94c83b 390
cha45689 0:389b4c94c83b 391 // wait for write to finish
cha45689 0:389b4c94c83b 392 while (_spi.write(0xFF) == 0);
cha45689 0:389b4c94c83b 393
cha45689 0:389b4c94c83b 394 _cs = 1;
cha45689 0:389b4c94c83b 395 _spi.write(0xFF);
cha45689 0:389b4c94c83b 396 return 0;
cha45689 0:389b4c94c83b 397 }
cha45689 0:389b4c94c83b 398
cha45689 0:389b4c94c83b 399 static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
cha45689 0:389b4c94c83b 400 uint32_t bits = 0;
cha45689 0:389b4c94c83b 401 uint32_t size = 1 + msb - lsb;
cha45689 0:389b4c94c83b 402 for (int i = 0; i < size; i++) {
cha45689 0:389b4c94c83b 403 uint32_t position = lsb + i;
cha45689 0:389b4c94c83b 404 uint32_t byte = 15 - (position >> 3);
cha45689 0:389b4c94c83b 405 uint32_t bit = position & 0x7;
cha45689 0:389b4c94c83b 406 uint32_t value = (data[byte] >> bit) & 1;
cha45689 0:389b4c94c83b 407 bits |= value << i;
cha45689 0:389b4c94c83b 408 }
cha45689 0:389b4c94c83b 409 return bits;
cha45689 0:389b4c94c83b 410 }
cha45689 0:389b4c94c83b 411
cha45689 0:389b4c94c83b 412 uint64_t SDFileSystem::_sd_sectors() {
cha45689 0:389b4c94c83b 413 uint32_t c_size, c_size_mult, read_bl_len;
cha45689 0:389b4c94c83b 414 uint32_t block_len, mult, blocknr, capacity;
cha45689 0:389b4c94c83b 415 uint32_t hc_c_size;
cha45689 0:389b4c94c83b 416 uint64_t blocks;
cha45689 0:389b4c94c83b 417
cha45689 0:389b4c94c83b 418 // CMD9, Response R2 (R1 byte + 16-byte block read)
cha45689 0:389b4c94c83b 419 if (_cmdx(9, 0) != 0) {
cha45689 0:389b4c94c83b 420 debug("Didn't get a response from the disk\n");
cha45689 0:389b4c94c83b 421 return 0;
cha45689 0:389b4c94c83b 422 }
cha45689 0:389b4c94c83b 423
cha45689 0:389b4c94c83b 424 uint8_t csd[16];
cha45689 0:389b4c94c83b 425 if (_read(csd, 16) != 0) {
cha45689 0:389b4c94c83b 426 debug("Couldn't read csd response from disk\n");
cha45689 0:389b4c94c83b 427 return 0;
cha45689 0:389b4c94c83b 428 }
cha45689 0:389b4c94c83b 429
cha45689 0:389b4c94c83b 430 // csd_structure : csd[127:126]
cha45689 0:389b4c94c83b 431 // c_size : csd[73:62]
cha45689 0:389b4c94c83b 432 // c_size_mult : csd[49:47]
cha45689 0:389b4c94c83b 433 // read_bl_len : csd[83:80] - the *maximum* read block length
cha45689 0:389b4c94c83b 434
cha45689 0:389b4c94c83b 435 int csd_structure = ext_bits(csd, 127, 126);
cha45689 0:389b4c94c83b 436
cha45689 0:389b4c94c83b 437 switch (csd_structure) {
cha45689 0:389b4c94c83b 438 case 0:
cha45689 0:389b4c94c83b 439 cdv = 512;
cha45689 0:389b4c94c83b 440 c_size = ext_bits(csd, 73, 62);
cha45689 0:389b4c94c83b 441 c_size_mult = ext_bits(csd, 49, 47);
cha45689 0:389b4c94c83b 442 read_bl_len = ext_bits(csd, 83, 80);
cha45689 0:389b4c94c83b 443
cha45689 0:389b4c94c83b 444 block_len = 1 << read_bl_len;
cha45689 0:389b4c94c83b 445 mult = 1 << (c_size_mult + 2);
cha45689 0:389b4c94c83b 446 blocknr = (c_size + 1) * mult;
cha45689 0:389b4c94c83b 447 capacity = blocknr * block_len;
cha45689 0:389b4c94c83b 448 blocks = capacity / 512;
cha45689 0:389b4c94c83b 449 debug_if(SD_DBG, "\n\rSDCard\n\rc_size: %d \n\rcapacity: %ld \n\rsectors: %lld\n\r", c_size, capacity, blocks);
cha45689 0:389b4c94c83b 450 break;
cha45689 0:389b4c94c83b 451
cha45689 0:389b4c94c83b 452 case 1:
cha45689 0:389b4c94c83b 453 cdv = 1;
cha45689 0:389b4c94c83b 454 hc_c_size = ext_bits(csd, 63, 48);
cha45689 0:389b4c94c83b 455 blocks = (hc_c_size+1)*1024;
cha45689 0:389b4c94c83b 456 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);
cha45689 0:389b4c94c83b 457 break;
cha45689 0:389b4c94c83b 458
cha45689 0:389b4c94c83b 459 default:
cha45689 0:389b4c94c83b 460 debug("CSD struct unsupported\r\n");
cha45689 0:389b4c94c83b 461 return 0;
cha45689 0:389b4c94c83b 462 };
cha45689 0:389b4c94c83b 463 return blocks;
cha45689 0:389b4c94c83b 464 }
cha45689 0:389b4c94c83b 465