Emilia Marino / SDFileSystem

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SDFileSystem.cpp@0:5f7b02d095c2, 2021-12-18 (annotated)

Committer:
emiliamarino
Date:
Sat Dec 18 20:17:31 2021 +0000
Revision:
0:5f7b02d095c2
Assignment 4

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emiliamarino 0:5f7b02d095c2 1 /* mbed Microcontroller Library
emiliamarino 0:5f7b02d095c2 2 * Copyright (c) 2006-2012 ARM Limited
emiliamarino 0:5f7b02d095c2 3 *
emiliamarino 0:5f7b02d095c2 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
emiliamarino 0:5f7b02d095c2 5 * of this software and associated documentation files (the "Software"), to deal
emiliamarino 0:5f7b02d095c2 6 * in the Software without restriction, including without limitation the rights
emiliamarino 0:5f7b02d095c2 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
emiliamarino 0:5f7b02d095c2 8 * copies of the Software, and to permit persons to whom the Software is
emiliamarino 0:5f7b02d095c2 9 * furnished to do so, subject to the following conditions:
emiliamarino 0:5f7b02d095c2 10 *
emiliamarino 0:5f7b02d095c2 11 * The above copyright notice and this permission notice shall be included in
emiliamarino 0:5f7b02d095c2 12 * all copies or substantial portions of the Software.
emiliamarino 0:5f7b02d095c2 13 *
emiliamarino 0:5f7b02d095c2 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
emiliamarino 0:5f7b02d095c2 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
emiliamarino 0:5f7b02d095c2 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
emiliamarino 0:5f7b02d095c2 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
emiliamarino 0:5f7b02d095c2 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
emiliamarino 0:5f7b02d095c2 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
emiliamarino 0:5f7b02d095c2 20 * SOFTWARE.
emiliamarino 0:5f7b02d095c2 21 */
emiliamarino 0:5f7b02d095c2 22 /* Introduction
emiliamarino 0:5f7b02d095c2 23 * ------------
emiliamarino 0:5f7b02d095c2 24 * SD and MMC cards support a number of interfaces, but common to them all
emiliamarino 0:5f7b02d095c2 25 * is one based on SPI. This is the one I'm implmenting because it means
emiliamarino 0:5f7b02d095c2 26 * it is much more portable even though not so performant, and we already
emiliamarino 0:5f7b02d095c2 27 * have the mbed SPI Interface!
emiliamarino 0:5f7b02d095c2 28 *
emiliamarino 0:5f7b02d095c2 29 * The main reference I'm using is Chapter 7, "SPI Mode" of:
emiliamarino 0:5f7b02d095c2 30 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
emiliamarino 0:5f7b02d095c2 31 *
emiliamarino 0:5f7b02d095c2 32 * SPI Startup
emiliamarino 0:5f7b02d095c2 33 * -----------
emiliamarino 0:5f7b02d095c2 34 * The SD card powers up in SD mode. The SPI interface mode is selected by
emiliamarino 0:5f7b02d095c2 35 * asserting CS low and sending the reset command (CMD0). The card will
emiliamarino 0:5f7b02d095c2 36 * respond with a (R1) response.
emiliamarino 0:5f7b02d095c2 37 *
emiliamarino 0:5f7b02d095c2 38 * CMD8 is optionally sent to determine the voltage range supported, and
emiliamarino 0:5f7b02d095c2 39 * indirectly determine whether it is a version 1.x SD/non-SD card or
emiliamarino 0:5f7b02d095c2 40 * version 2.x. I'll just ignore this for now.
emiliamarino 0:5f7b02d095c2 41 *
emiliamarino 0:5f7b02d095c2 42 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
emiliamarino 0:5f7b02d095c2 43 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
emiliamarino 0:5f7b02d095c2 44 *
emiliamarino 0:5f7b02d095c2 45 * You should also indicate whether the host supports High Capicity cards,
emiliamarino 0:5f7b02d095c2 46 * and check whether the card is high capacity - i'll also ignore this
emiliamarino 0:5f7b02d095c2 47 *
emiliamarino 0:5f7b02d095c2 48 * SPI Protocol
emiliamarino 0:5f7b02d095c2 49 * ------------
emiliamarino 0:5f7b02d095c2 50 * The SD SPI protocol is based on transactions made up of 8-bit words, with
emiliamarino 0:5f7b02d095c2 51 * the host starting every bus transaction by asserting the CS signal low. The
emiliamarino 0:5f7b02d095c2 52 * card always responds to commands, data blocks and errors.
emiliamarino 0:5f7b02d095c2 53 *
emiliamarino 0:5f7b02d095c2 54 * The protocol supports a CRC, but by default it is off (except for the
emiliamarino 0:5f7b02d095c2 55 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
emiliamarino 0:5f7b02d095c2 56 * I'll leave the CRC off I think!
emiliamarino 0:5f7b02d095c2 57 *
emiliamarino 0:5f7b02d095c2 58 * Standard capacity cards have variable data block sizes, whereas High
emiliamarino 0:5f7b02d095c2 59 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
emiliamarino 0:5f7b02d095c2 60 * just always use the Standard Capacity cards with a block size of 512 bytes.
emiliamarino 0:5f7b02d095c2 61 * This is set with CMD16.
emiliamarino 0:5f7b02d095c2 62 *
emiliamarino 0:5f7b02d095c2 63 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
emiliamarino 0:5f7b02d095c2 64 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
emiliamarino 0:5f7b02d095c2 65 * the card gets a read command, it responds with a response token, and then
emiliamarino 0:5f7b02d095c2 66 * a data token or an error.
emiliamarino 0:5f7b02d095c2 67 *
emiliamarino 0:5f7b02d095c2 68 * SPI Command Format
emiliamarino 0:5f7b02d095c2 69 * ------------------
emiliamarino 0:5f7b02d095c2 70 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
emiliamarino 0:5f7b02d095c2 71 *
emiliamarino 0:5f7b02d095c2 72 * +---------------+------------+------------+-----------+----------+--------------+
emiliamarino 0:5f7b02d095c2 73 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
emiliamarino 0:5f7b02d095c2 74 * +---------------+------------+------------+-----------+----------+--------------+
emiliamarino 0:5f7b02d095c2 75 *
emiliamarino 0:5f7b02d095c2 76 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
emiliamarino 0:5f7b02d095c2 77 *
emiliamarino 0:5f7b02d095c2 78 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
emiliamarino 0:5f7b02d095c2 79 *
emiliamarino 0:5f7b02d095c2 80 * SPI Response Format
emiliamarino 0:5f7b02d095c2 81 * -------------------
emiliamarino 0:5f7b02d095c2 82 * The main response format (R1) is a status byte (normally zero). Key flags:
emiliamarino 0:5f7b02d095c2 83 * idle - 1 if the card is in an idle state/initialising
emiliamarino 0:5f7b02d095c2 84 * cmd - 1 if an illegal command code was detected
emiliamarino 0:5f7b02d095c2 85 *
emiliamarino 0:5f7b02d095c2 86 * +-------------------------------------------------+
emiliamarino 0:5f7b02d095c2 87 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
emiliamarino 0:5f7b02d095c2 88 * +-------------------------------------------------+
emiliamarino 0:5f7b02d095c2 89 *
emiliamarino 0:5f7b02d095c2 90 * R1b is the same, except it is followed by a busy signal (zeros) until
emiliamarino 0:5f7b02d095c2 91 * the first non-zero byte when it is ready again.
emiliamarino 0:5f7b02d095c2 92 *
emiliamarino 0:5f7b02d095c2 93 * Data Response Token
emiliamarino 0:5f7b02d095c2 94 * -------------------
emiliamarino 0:5f7b02d095c2 95 * Every data block written to the card is acknowledged by a byte
emiliamarino 0:5f7b02d095c2 96 * response token
emiliamarino 0:5f7b02d095c2 97 *
emiliamarino 0:5f7b02d095c2 98 * +----------------------+
emiliamarino 0:5f7b02d095c2 99 * | xxx | 0 | status | 1 |
emiliamarino 0:5f7b02d095c2 100 * +----------------------+
emiliamarino 0:5f7b02d095c2 101 * 010 - OK!
emiliamarino 0:5f7b02d095c2 102 * 101 - CRC Error
emiliamarino 0:5f7b02d095c2 103 * 110 - Write Error
emiliamarino 0:5f7b02d095c2 104 *
emiliamarino 0:5f7b02d095c2 105 * Single Block Read and Write
emiliamarino 0:5f7b02d095c2 106 * ---------------------------
emiliamarino 0:5f7b02d095c2 107 *
emiliamarino 0:5f7b02d095c2 108 * Block transfers have a byte header, followed by the data, followed
emiliamarino 0:5f7b02d095c2 109 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
emiliamarino 0:5f7b02d095c2 110 *
emiliamarino 0:5f7b02d095c2 111 * +------+---------+---------+- - - -+---------+-----------+----------+
emiliamarino 0:5f7b02d095c2 112 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
emiliamarino 0:5f7b02d095c2 113 * +------+---------+---------+- - - -+---------+-----------+----------+
emiliamarino 0:5f7b02d095c2 114 */
emiliamarino 0:5f7b02d095c2 115 #include "SDFileSystem.h"
emiliamarino 0:5f7b02d095c2 116 #include "mbed_debug.h"
emiliamarino 0:5f7b02d095c2 117
emiliamarino 0:5f7b02d095c2 118 #define SD_COMMAND_TIMEOUT 5000
emiliamarino 0:5f7b02d095c2 119
emiliamarino 0:5f7b02d095c2 120 #define SD_DBG 0
emiliamarino 0:5f7b02d095c2 121
emiliamarino 0:5f7b02d095c2 122 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
emiliamarino 0:5f7b02d095c2 123 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs), _is_initialized(0) {
emiliamarino 0:5f7b02d095c2 124 _cs = 1;
emiliamarino 0:5f7b02d095c2 125
emiliamarino 0:5f7b02d095c2 126 // Set default to 100kHz for initialisation and 1MHz for data transfer
emiliamarino 0:5f7b02d095c2 127 _init_sck = 100000;
emiliamarino 0:5f7b02d095c2 128 _transfer_sck = 1000000;
emiliamarino 0:5f7b02d095c2 129 }
emiliamarino 0:5f7b02d095c2 130
emiliamarino 0:5f7b02d095c2 131 #define R1_IDLE_STATE (1 << 0)
emiliamarino 0:5f7b02d095c2 132 #define R1_ERASE_RESET (1 << 1)
emiliamarino 0:5f7b02d095c2 133 #define R1_ILLEGAL_COMMAND (1 << 2)
emiliamarino 0:5f7b02d095c2 134 #define R1_COM_CRC_ERROR (1 << 3)
emiliamarino 0:5f7b02d095c2 135 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
emiliamarino 0:5f7b02d095c2 136 #define R1_ADDRESS_ERROR (1 << 5)
emiliamarino 0:5f7b02d095c2 137 #define R1_PARAMETER_ERROR (1 << 6)
emiliamarino 0:5f7b02d095c2 138
emiliamarino 0:5f7b02d095c2 139 // Types
emiliamarino 0:5f7b02d095c2 140 // - v1.x Standard Capacity
emiliamarino 0:5f7b02d095c2 141 // - v2.x Standard Capacity
emiliamarino 0:5f7b02d095c2 142 // - v2.x High Capacity
emiliamarino 0:5f7b02d095c2 143 // - Not recognised as an SD Card
emiliamarino 0:5f7b02d095c2 144 #define SDCARD_FAIL 0
emiliamarino 0:5f7b02d095c2 145 #define SDCARD_V1 1
emiliamarino 0:5f7b02d095c2 146 #define SDCARD_V2 2
emiliamarino 0:5f7b02d095c2 147 #define SDCARD_V2HC 3
emiliamarino 0:5f7b02d095c2 148
emiliamarino 0:5f7b02d095c2 149 int SDFileSystem::initialise_card() {
emiliamarino 0:5f7b02d095c2 150 // Set to SCK for initialisation, and clock card with cs = 1
emiliamarino 0:5f7b02d095c2 151 _spi.frequency(_init_sck);
emiliamarino 0:5f7b02d095c2 152 _cs = 1;
emiliamarino 0:5f7b02d095c2 153 for (int i = 0; i < 16; i++) {
emiliamarino 0:5f7b02d095c2 154 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 155 }
emiliamarino 0:5f7b02d095c2 156
emiliamarino 0:5f7b02d095c2 157 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
emiliamarino 0:5f7b02d095c2 158 if (_cmd(0, 0) != R1_IDLE_STATE) {
emiliamarino 0:5f7b02d095c2 159 debug("No disk, or could not put SD card in to SPI idle state\n");
emiliamarino 0:5f7b02d095c2 160 return SDCARD_FAIL;
emiliamarino 0:5f7b02d095c2 161 }
emiliamarino 0:5f7b02d095c2 162
emiliamarino 0:5f7b02d095c2 163 // send CMD8 to determine whther it is ver 2.x
emiliamarino 0:5f7b02d095c2 164 int r = _cmd8();
emiliamarino 0:5f7b02d095c2 165 if (r == R1_IDLE_STATE) {
emiliamarino 0:5f7b02d095c2 166 return initialise_card_v2();
emiliamarino 0:5f7b02d095c2 167 } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
emiliamarino 0:5f7b02d095c2 168 return initialise_card_v1();
emiliamarino 0:5f7b02d095c2 169 } else {
emiliamarino 0:5f7b02d095c2 170 debug("Not in idle state after sending CMD8 (not an SD card?)\n");
emiliamarino 0:5f7b02d095c2 171 return SDCARD_FAIL;
emiliamarino 0:5f7b02d095c2 172 }
emiliamarino 0:5f7b02d095c2 173 }
emiliamarino 0:5f7b02d095c2 174
emiliamarino 0:5f7b02d095c2 175 int SDFileSystem::initialise_card_v1() {
emiliamarino 0:5f7b02d095c2 176 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
emiliamarino 0:5f7b02d095c2 177 _cmd(55, 0);
emiliamarino 0:5f7b02d095c2 178 if (_cmd(41, 0) == 0) {
emiliamarino 0:5f7b02d095c2 179 cdv = 512;
emiliamarino 0:5f7b02d095c2 180 debug_if(SD_DBG, "\n\rInit: SEDCARD_V1\n\r");
emiliamarino 0:5f7b02d095c2 181 return SDCARD_V1;
emiliamarino 0:5f7b02d095c2 182 }
emiliamarino 0:5f7b02d095c2 183 }
emiliamarino 0:5f7b02d095c2 184
emiliamarino 0:5f7b02d095c2 185 debug("Timeout waiting for v1.x card\n");
emiliamarino 0:5f7b02d095c2 186 return SDCARD_FAIL;
emiliamarino 0:5f7b02d095c2 187 }
emiliamarino 0:5f7b02d095c2 188
emiliamarino 0:5f7b02d095c2 189 int SDFileSystem::initialise_card_v2() {
emiliamarino 0:5f7b02d095c2 190 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
emiliamarino 0:5f7b02d095c2 191 wait_ms(50);
emiliamarino 0:5f7b02d095c2 192 _cmd58();
emiliamarino 0:5f7b02d095c2 193 _cmd(55, 0);
emiliamarino 0:5f7b02d095c2 194 if (_cmd(41, 0x40000000) == 0) {
emiliamarino 0:5f7b02d095c2 195 _cmd58();
emiliamarino 0:5f7b02d095c2 196 debug_if(SD_DBG, "\n\rInit: SDCARD_V2\n\r");
emiliamarino 0:5f7b02d095c2 197 cdv = 1;
emiliamarino 0:5f7b02d095c2 198 return SDCARD_V2;
emiliamarino 0:5f7b02d095c2 199 }
emiliamarino 0:5f7b02d095c2 200 }
emiliamarino 0:5f7b02d095c2 201
emiliamarino 0:5f7b02d095c2 202 debug("Timeout waiting for v2.x card\n");
emiliamarino 0:5f7b02d095c2 203 return SDCARD_FAIL;
emiliamarino 0:5f7b02d095c2 204 }
emiliamarino 0:5f7b02d095c2 205
emiliamarino 0:5f7b02d095c2 206 int SDFileSystem::disk_initialize() {
emiliamarino 0:5f7b02d095c2 207 _is_initialized = initialise_card();
emiliamarino 0:5f7b02d095c2 208 if (_is_initialized == 0) {
emiliamarino 0:5f7b02d095c2 209 debug("Fail to initialize card\n");
emiliamarino 0:5f7b02d095c2 210 return 1;
emiliamarino 0:5f7b02d095c2 211 }
emiliamarino 0:5f7b02d095c2 212 debug_if(SD_DBG, "init card = %d\n", _is_initialized);
emiliamarino 0:5f7b02d095c2 213 _sectors = _sd_sectors();
emiliamarino 0:5f7b02d095c2 214
emiliamarino 0:5f7b02d095c2 215 // Set block length to 512 (CMD16)
emiliamarino 0:5f7b02d095c2 216 if (_cmd(16, 512) != 0) {
emiliamarino 0:5f7b02d095c2 217 debug("Set 512-byte block timed out\n");
emiliamarino 0:5f7b02d095c2 218 return 1;
emiliamarino 0:5f7b02d095c2 219 }
emiliamarino 0:5f7b02d095c2 220
emiliamarino 0:5f7b02d095c2 221 // Set SCK for data transfer
emiliamarino 0:5f7b02d095c2 222 _spi.frequency(_transfer_sck);
emiliamarino 0:5f7b02d095c2 223 return 0;
emiliamarino 0:5f7b02d095c2 224 }
emiliamarino 0:5f7b02d095c2 225
emiliamarino 0:5f7b02d095c2 226 int SDFileSystem::disk_write(const uint8_t* buffer, uint32_t block_number, uint32_t count) {
emiliamarino 0:5f7b02d095c2 227 if (!_is_initialized) {
emiliamarino 0:5f7b02d095c2 228 return -1;
emiliamarino 0:5f7b02d095c2 229 }
emiliamarino 0:5f7b02d095c2 230
emiliamarino 0:5f7b02d095c2 231 for (uint32_t b = block_number; b < block_number + count; b++) {
emiliamarino 0:5f7b02d095c2 232 // set write address for single block (CMD24)
emiliamarino 0:5f7b02d095c2 233 if (_cmd(24, b * cdv) != 0) {
emiliamarino 0:5f7b02d095c2 234 return 1;
emiliamarino 0:5f7b02d095c2 235 }
emiliamarino 0:5f7b02d095c2 236
emiliamarino 0:5f7b02d095c2 237 // send the data block
emiliamarino 0:5f7b02d095c2 238 _write(buffer, 512);
emiliamarino 0:5f7b02d095c2 239 buffer += 512;
emiliamarino 0:5f7b02d095c2 240 }
emiliamarino 0:5f7b02d095c2 241
emiliamarino 0:5f7b02d095c2 242 return 0;
emiliamarino 0:5f7b02d095c2 243 }
emiliamarino 0:5f7b02d095c2 244
emiliamarino 0:5f7b02d095c2 245 int SDFileSystem::disk_read(uint8_t* buffer, uint32_t block_number, uint32_t count) {
emiliamarino 0:5f7b02d095c2 246 if (!_is_initialized) {
emiliamarino 0:5f7b02d095c2 247 return -1;
emiliamarino 0:5f7b02d095c2 248 }
emiliamarino 0:5f7b02d095c2 249
emiliamarino 0:5f7b02d095c2 250 for (uint32_t b = block_number; b < block_number + count; b++) {
emiliamarino 0:5f7b02d095c2 251 // set read address for single block (CMD17)
emiliamarino 0:5f7b02d095c2 252 if (_cmd(17, b * cdv) != 0) {
emiliamarino 0:5f7b02d095c2 253 return 1;
emiliamarino 0:5f7b02d095c2 254 }
emiliamarino 0:5f7b02d095c2 255
emiliamarino 0:5f7b02d095c2 256 // receive the data
emiliamarino 0:5f7b02d095c2 257 _read(buffer, 512);
emiliamarino 0:5f7b02d095c2 258 buffer += 512;
emiliamarino 0:5f7b02d095c2 259 }
emiliamarino 0:5f7b02d095c2 260
emiliamarino 0:5f7b02d095c2 261 return 0;
emiliamarino 0:5f7b02d095c2 262 }
emiliamarino 0:5f7b02d095c2 263
emiliamarino 0:5f7b02d095c2 264 int SDFileSystem::disk_status() {
emiliamarino 0:5f7b02d095c2 265 // FATFileSystem::disk_status() returns 0 when initialized
emiliamarino 0:5f7b02d095c2 266 if (_is_initialized) {
emiliamarino 0:5f7b02d095c2 267 return 0;
emiliamarino 0:5f7b02d095c2 268 } else {
emiliamarino 0:5f7b02d095c2 269 return 1;
emiliamarino 0:5f7b02d095c2 270 }
emiliamarino 0:5f7b02d095c2 271 }
emiliamarino 0:5f7b02d095c2 272
emiliamarino 0:5f7b02d095c2 273 int SDFileSystem::disk_sync() { return 0; }
emiliamarino 0:5f7b02d095c2 274 uint32_t SDFileSystem::disk_sectors() { return _sectors; }
emiliamarino 0:5f7b02d095c2 275
emiliamarino 0:5f7b02d095c2 276
emiliamarino 0:5f7b02d095c2 277 // PRIVATE FUNCTIONS
emiliamarino 0:5f7b02d095c2 278 int SDFileSystem::_cmd(int cmd, int arg) {
emiliamarino 0:5f7b02d095c2 279 _cs = 0;
emiliamarino 0:5f7b02d095c2 280
emiliamarino 0:5f7b02d095c2 281 // send a command
emiliamarino 0:5f7b02d095c2 282 _spi.write(0x40 | cmd);
emiliamarino 0:5f7b02d095c2 283 _spi.write(arg >> 24);
emiliamarino 0:5f7b02d095c2 284 _spi.write(arg >> 16);
emiliamarino 0:5f7b02d095c2 285 _spi.write(arg >> 8);
emiliamarino 0:5f7b02d095c2 286 _spi.write(arg >> 0);
emiliamarino 0:5f7b02d095c2 287 _spi.write(0x95);
emiliamarino 0:5f7b02d095c2 288
emiliamarino 0:5f7b02d095c2 289 // wait for the repsonse (response[7] == 0)
emiliamarino 0:5f7b02d095c2 290 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
emiliamarino 0:5f7b02d095c2 291 int response = _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 292 if (!(response & 0x80)) {
emiliamarino 0:5f7b02d095c2 293 _cs = 1;
emiliamarino 0:5f7b02d095c2 294 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 295 return response;
emiliamarino 0:5f7b02d095c2 296 }
emiliamarino 0:5f7b02d095c2 297 }
emiliamarino 0:5f7b02d095c2 298 _cs = 1;
emiliamarino 0:5f7b02d095c2 299 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 300 return -1; // timeout
emiliamarino 0:5f7b02d095c2 301 }
emiliamarino 0:5f7b02d095c2 302 int SDFileSystem::_cmdx(int cmd, int arg) {
emiliamarino 0:5f7b02d095c2 303 _cs = 0;
emiliamarino 0:5f7b02d095c2 304
emiliamarino 0:5f7b02d095c2 305 // send a command
emiliamarino 0:5f7b02d095c2 306 _spi.write(0x40 | cmd);
emiliamarino 0:5f7b02d095c2 307 _spi.write(arg >> 24);
emiliamarino 0:5f7b02d095c2 308 _spi.write(arg >> 16);
emiliamarino 0:5f7b02d095c2 309 _spi.write(arg >> 8);
emiliamarino 0:5f7b02d095c2 310 _spi.write(arg >> 0);
emiliamarino 0:5f7b02d095c2 311 _spi.write(0x95);
emiliamarino 0:5f7b02d095c2 312
emiliamarino 0:5f7b02d095c2 313 // wait for the repsonse (response[7] == 0)
emiliamarino 0:5f7b02d095c2 314 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
emiliamarino 0:5f7b02d095c2 315 int response = _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 316 if (!(response & 0x80)) {
emiliamarino 0:5f7b02d095c2 317 return response;
emiliamarino 0:5f7b02d095c2 318 }
emiliamarino 0:5f7b02d095c2 319 }
emiliamarino 0:5f7b02d095c2 320 _cs = 1;
emiliamarino 0:5f7b02d095c2 321 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 322 return -1; // timeout
emiliamarino 0:5f7b02d095c2 323 }
emiliamarino 0:5f7b02d095c2 324
emiliamarino 0:5f7b02d095c2 325
emiliamarino 0:5f7b02d095c2 326 int SDFileSystem::_cmd58() {
emiliamarino 0:5f7b02d095c2 327 _cs = 0;
emiliamarino 0:5f7b02d095c2 328 int arg = 0;
emiliamarino 0:5f7b02d095c2 329
emiliamarino 0:5f7b02d095c2 330 // send a command
emiliamarino 0:5f7b02d095c2 331 _spi.write(0x40 | 58);
emiliamarino 0:5f7b02d095c2 332 _spi.write(arg >> 24);
emiliamarino 0:5f7b02d095c2 333 _spi.write(arg >> 16);
emiliamarino 0:5f7b02d095c2 334 _spi.write(arg >> 8);
emiliamarino 0:5f7b02d095c2 335 _spi.write(arg >> 0);
emiliamarino 0:5f7b02d095c2 336 _spi.write(0x95);
emiliamarino 0:5f7b02d095c2 337
emiliamarino 0:5f7b02d095c2 338 // wait for the repsonse (response[7] == 0)
emiliamarino 0:5f7b02d095c2 339 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
emiliamarino 0:5f7b02d095c2 340 int response = _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 341 if (!(response & 0x80)) {
emiliamarino 0:5f7b02d095c2 342 int ocr = _spi.write(0xFF) << 24;
emiliamarino 0:5f7b02d095c2 343 ocr |= _spi.write(0xFF) << 16;
emiliamarino 0:5f7b02d095c2 344 ocr |= _spi.write(0xFF) << 8;
emiliamarino 0:5f7b02d095c2 345 ocr |= _spi.write(0xFF) << 0;
emiliamarino 0:5f7b02d095c2 346 _cs = 1;
emiliamarino 0:5f7b02d095c2 347 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 348 return response;
emiliamarino 0:5f7b02d095c2 349 }
emiliamarino 0:5f7b02d095c2 350 }
emiliamarino 0:5f7b02d095c2 351 _cs = 1;
emiliamarino 0:5f7b02d095c2 352 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 353 return -1; // timeout
emiliamarino 0:5f7b02d095c2 354 }
emiliamarino 0:5f7b02d095c2 355
emiliamarino 0:5f7b02d095c2 356 int SDFileSystem::_cmd8() {
emiliamarino 0:5f7b02d095c2 357 _cs = 0;
emiliamarino 0:5f7b02d095c2 358
emiliamarino 0:5f7b02d095c2 359 // send a command
emiliamarino 0:5f7b02d095c2 360 _spi.write(0x40 | 8); // CMD8
emiliamarino 0:5f7b02d095c2 361 _spi.write(0x00); // reserved
emiliamarino 0:5f7b02d095c2 362 _spi.write(0x00); // reserved
emiliamarino 0:5f7b02d095c2 363 _spi.write(0x01); // 3.3v
emiliamarino 0:5f7b02d095c2 364 _spi.write(0xAA); // check pattern
emiliamarino 0:5f7b02d095c2 365 _spi.write(0x87); // crc
emiliamarino 0:5f7b02d095c2 366
emiliamarino 0:5f7b02d095c2 367 // wait for the repsonse (response[7] == 0)
emiliamarino 0:5f7b02d095c2 368 for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
emiliamarino 0:5f7b02d095c2 369 char response[5];
emiliamarino 0:5f7b02d095c2 370 response[0] = _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 371 if (!(response[0] & 0x80)) {
emiliamarino 0:5f7b02d095c2 372 for (int j = 1; j < 5; j++) {
emiliamarino 0:5f7b02d095c2 373 response[i] = _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 374 }
emiliamarino 0:5f7b02d095c2 375 _cs = 1;
emiliamarino 0:5f7b02d095c2 376 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 377 return response[0];
emiliamarino 0:5f7b02d095c2 378 }
emiliamarino 0:5f7b02d095c2 379 }
emiliamarino 0:5f7b02d095c2 380 _cs = 1;
emiliamarino 0:5f7b02d095c2 381 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 382 return -1; // timeout
emiliamarino 0:5f7b02d095c2 383 }
emiliamarino 0:5f7b02d095c2 384
emiliamarino 0:5f7b02d095c2 385 int SDFileSystem::_read(uint8_t *buffer, uint32_t length) {
emiliamarino 0:5f7b02d095c2 386 _cs = 0;
emiliamarino 0:5f7b02d095c2 387
emiliamarino 0:5f7b02d095c2 388 // read until start byte (0xFF)
emiliamarino 0:5f7b02d095c2 389 while (_spi.write(0xFF) != 0xFE);
emiliamarino 0:5f7b02d095c2 390
emiliamarino 0:5f7b02d095c2 391 // read data
emiliamarino 0:5f7b02d095c2 392 for (uint32_t i = 0; i < length; i++) {
emiliamarino 0:5f7b02d095c2 393 buffer[i] = _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 394 }
emiliamarino 0:5f7b02d095c2 395 _spi.write(0xFF); // checksum
emiliamarino 0:5f7b02d095c2 396 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 397
emiliamarino 0:5f7b02d095c2 398 _cs = 1;
emiliamarino 0:5f7b02d095c2 399 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 400 return 0;
emiliamarino 0:5f7b02d095c2 401 }
emiliamarino 0:5f7b02d095c2 402
emiliamarino 0:5f7b02d095c2 403 int SDFileSystem::_write(const uint8_t*buffer, uint32_t length) {
emiliamarino 0:5f7b02d095c2 404 _cs = 0;
emiliamarino 0:5f7b02d095c2 405
emiliamarino 0:5f7b02d095c2 406 // indicate start of block
emiliamarino 0:5f7b02d095c2 407 _spi.write(0xFE);
emiliamarino 0:5f7b02d095c2 408
emiliamarino 0:5f7b02d095c2 409 // write the data
emiliamarino 0:5f7b02d095c2 410 for (uint32_t i = 0; i < length; i++) {
emiliamarino 0:5f7b02d095c2 411 _spi.write(buffer[i]);
emiliamarino 0:5f7b02d095c2 412 }
emiliamarino 0:5f7b02d095c2 413
emiliamarino 0:5f7b02d095c2 414 // write the checksum
emiliamarino 0:5f7b02d095c2 415 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 416 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 417
emiliamarino 0:5f7b02d095c2 418 // check the response token
emiliamarino 0:5f7b02d095c2 419 if ((_spi.write(0xFF) & 0x1F) != 0x05) {
emiliamarino 0:5f7b02d095c2 420 _cs = 1;
emiliamarino 0:5f7b02d095c2 421 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 422 return 1;
emiliamarino 0:5f7b02d095c2 423 }
emiliamarino 0:5f7b02d095c2 424
emiliamarino 0:5f7b02d095c2 425 // wait for write to finish
emiliamarino 0:5f7b02d095c2 426 while (_spi.write(0xFF) == 0);
emiliamarino 0:5f7b02d095c2 427
emiliamarino 0:5f7b02d095c2 428 _cs = 1;
emiliamarino 0:5f7b02d095c2 429 _spi.write(0xFF);
emiliamarino 0:5f7b02d095c2 430 return 0;
emiliamarino 0:5f7b02d095c2 431 }
emiliamarino 0:5f7b02d095c2 432
emiliamarino 0:5f7b02d095c2 433 static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
emiliamarino 0:5f7b02d095c2 434 uint32_t bits = 0;
emiliamarino 0:5f7b02d095c2 435 uint32_t size = 1 + msb - lsb;
emiliamarino 0:5f7b02d095c2 436 for (uint32_t i = 0; i < size; i++) {
emiliamarino 0:5f7b02d095c2 437 uint32_t position = lsb + i;
emiliamarino 0:5f7b02d095c2 438 uint32_t byte = 15 - (position >> 3);
emiliamarino 0:5f7b02d095c2 439 uint32_t bit = position & 0x7;
emiliamarino 0:5f7b02d095c2 440 uint32_t value = (data[byte] >> bit) & 1;
emiliamarino 0:5f7b02d095c2 441 bits |= value << i;
emiliamarino 0:5f7b02d095c2 442 }
emiliamarino 0:5f7b02d095c2 443 return bits;
emiliamarino 0:5f7b02d095c2 444 }
emiliamarino 0:5f7b02d095c2 445
emiliamarino 0:5f7b02d095c2 446 uint32_t SDFileSystem::_sd_sectors() {
emiliamarino 0:5f7b02d095c2 447 uint32_t c_size, c_size_mult, read_bl_len;
emiliamarino 0:5f7b02d095c2 448 uint32_t block_len, mult, blocknr, capacity;
emiliamarino 0:5f7b02d095c2 449 uint32_t hc_c_size;
emiliamarino 0:5f7b02d095c2 450 uint32_t blocks;
emiliamarino 0:5f7b02d095c2 451
emiliamarino 0:5f7b02d095c2 452 // CMD9, Response R2 (R1 byte + 16-byte block read)
emiliamarino 0:5f7b02d095c2 453 if (_cmdx(9, 0) != 0) {
emiliamarino 0:5f7b02d095c2 454 debug("Didn't get a response from the disk\n");
emiliamarino 0:5f7b02d095c2 455 return 0;
emiliamarino 0:5f7b02d095c2 456 }
emiliamarino 0:5f7b02d095c2 457
emiliamarino 0:5f7b02d095c2 458 uint8_t csd[16];
emiliamarino 0:5f7b02d095c2 459 if (_read(csd, 16) != 0) {
emiliamarino 0:5f7b02d095c2 460 debug("Couldn't read csd response from disk\n");
emiliamarino 0:5f7b02d095c2 461 return 0;
emiliamarino 0:5f7b02d095c2 462 }
emiliamarino 0:5f7b02d095c2 463
emiliamarino 0:5f7b02d095c2 464 // csd_structure : csd[127:126]
emiliamarino 0:5f7b02d095c2 465 // c_size : csd[73:62]
emiliamarino 0:5f7b02d095c2 466 // c_size_mult : csd[49:47]
emiliamarino 0:5f7b02d095c2 467 // read_bl_len : csd[83:80] - the *maximum* read block length
emiliamarino 0:5f7b02d095c2 468
emiliamarino 0:5f7b02d095c2 469 int csd_structure = ext_bits(csd, 127, 126);
emiliamarino 0:5f7b02d095c2 470
emiliamarino 0:5f7b02d095c2 471 switch (csd_structure) {
emiliamarino 0:5f7b02d095c2 472 case 0:
emiliamarino 0:5f7b02d095c2 473 cdv = 512;
emiliamarino 0:5f7b02d095c2 474 c_size = ext_bits(csd, 73, 62);
emiliamarino 0:5f7b02d095c2 475 c_size_mult = ext_bits(csd, 49, 47);
emiliamarino 0:5f7b02d095c2 476 read_bl_len = ext_bits(csd, 83, 80);
emiliamarino 0:5f7b02d095c2 477
emiliamarino 0:5f7b02d095c2 478 block_len = 1 << read_bl_len;
emiliamarino 0:5f7b02d095c2 479 mult = 1 << (c_size_mult + 2);
emiliamarino 0:5f7b02d095c2 480 blocknr = (c_size + 1) * mult;
emiliamarino 0:5f7b02d095c2 481 capacity = blocknr * block_len;
emiliamarino 0:5f7b02d095c2 482 blocks = capacity / 512;
emiliamarino 0:5f7b02d095c2 483 debug_if(SD_DBG, "\n\rSDCard\n\rc_size: %d \n\rcapacity: %ld \n\rsectors: %lld\n\r", c_size, capacity, blocks);
emiliamarino 0:5f7b02d095c2 484 break;
emiliamarino 0:5f7b02d095c2 485
emiliamarino 0:5f7b02d095c2 486 case 1:
emiliamarino 0:5f7b02d095c2 487 cdv = 1;
emiliamarino 0:5f7b02d095c2 488 hc_c_size = ext_bits(csd, 63, 48);
emiliamarino 0:5f7b02d095c2 489 blocks = (hc_c_size+1)*1024;
emiliamarino 0:5f7b02d095c2 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);
emiliamarino 0:5f7b02d095c2 491 break;
emiliamarino 0:5f7b02d095c2 492
emiliamarino 0:5f7b02d095c2 493 default:
emiliamarino 0:5f7b02d095c2 494 debug("CSD struct unsupported\r\n");
emiliamarino 0:5f7b02d095c2 495 return 0;
emiliamarino 0:5f7b02d095c2 496 };
emiliamarino 0:5f7b02d095c2 497 return blocks;
emiliamarino 0:5f7b02d095c2 498 }