virtualmech / Mbed 2 deprecated vmConfort_v6

Esta versión v6 pasa a ser el nuevo master. Funciona correctamente

Dependencies:   ADXL345 Display1602 MSCFileSystem SDFileSystem mbed FATFileSystem

SDFileSystem/SDFileSystem.cpp@2:cc4a43d806e2, 2014-06-06 (annotated)

Committer:
JuanManuelAmador
Date:
Fri Jun 06 08:52:28 2014 +0000
Revision:
2:cc4a43d806e2
Parent:
0:a5367bd4e404 
Correci?n del baudrate de 112500 a 115200

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jjmedina 0:a5367bd4e404 1 /* mbed SDFileSystem Library, for providing file access to SD cards
jjmedina 0:a5367bd4e404 2 * Copyright (c) 2008-2010, sford
jjmedina 0:a5367bd4e404 3 *
jjmedina 0:a5367bd4e404 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
jjmedina 0:a5367bd4e404 5 * of this software and associated documentation files (the "Software"), to deal
jjmedina 0:a5367bd4e404 6 * in the Software without restriction, including without limitation the rights
jjmedina 0:a5367bd4e404 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
jjmedina 0:a5367bd4e404 8 * copies of the Software, and to permit persons to whom the Software is
jjmedina 0:a5367bd4e404 9 * furnished to do so, subject to the following conditions:
jjmedina 0:a5367bd4e404 10 *
jjmedina 0:a5367bd4e404 11 * The above copyright notice and this permission notice shall be included in
jjmedina 0:a5367bd4e404 12 * all copies or substantial portions of the Software.
jjmedina 0:a5367bd4e404 13 *
jjmedina 0:a5367bd4e404 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
jjmedina 0:a5367bd4e404 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
jjmedina 0:a5367bd4e404 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
jjmedina 0:a5367bd4e404 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
jjmedina 0:a5367bd4e404 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
jjmedina 0:a5367bd4e404 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
jjmedina 0:a5367bd4e404 20 * THE SOFTWARE.
jjmedina 0:a5367bd4e404 21 */
jjmedina 0:a5367bd4e404 22
jjmedina 0:a5367bd4e404 23 /* Introduction
jjmedina 0:a5367bd4e404 24 * ------------
jjmedina 0:a5367bd4e404 25 * SD and MMC cards support a number of interfaces, but common to them all
jjmedina 0:a5367bd4e404 26 * is one based on SPI. This is the one I'm implmenting because it means
jjmedina 0:a5367bd4e404 27 * it is much more portable even though not so performant, and we already
jjmedina 0:a5367bd4e404 28 * have the mbed SPI Interface!
jjmedina 0:a5367bd4e404 29 *
jjmedina 0:a5367bd4e404 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
jjmedina 0:a5367bd4e404 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
jjmedina 0:a5367bd4e404 32 *
jjmedina 0:a5367bd4e404 33 * SPI Startup
jjmedina 0:a5367bd4e404 34 * -----------
jjmedina 0:a5367bd4e404 35 * The SD card powers up in SD mode. The SPI interface mode is selected by
jjmedina 0:a5367bd4e404 36 * asserting CS low and sending the reset command (CMD0). The card will
jjmedina 0:a5367bd4e404 37 * respond with a (R1) response.
jjmedina 0:a5367bd4e404 38 *
jjmedina 0:a5367bd4e404 39 * CMD8 is optionally sent to determine the voltage range supported, and
jjmedina 0:a5367bd4e404 40 * indirectly determine whether it is a version 1.x SD/non-SD card or
jjmedina 0:a5367bd4e404 41 * version 2.x. I'll just ignore this for now.
jjmedina 0:a5367bd4e404 42 *
jjmedina 0:a5367bd4e404 43 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
jjmedina 0:a5367bd4e404 44 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
jjmedina 0:a5367bd4e404 45 *
jjmedina 0:a5367bd4e404 46 * You should also indicate whether the host supports High Capicity cards,
jjmedina 0:a5367bd4e404 47 * and check whether the card is high capacity - i'll also ignore this
jjmedina 0:a5367bd4e404 48 *
jjmedina 0:a5367bd4e404 49 * SPI Protocol
jjmedina 0:a5367bd4e404 50 * ------------
jjmedina 0:a5367bd4e404 51 * The SD SPI protocol is based on transactions made up of 8-bit words, with
jjmedina 0:a5367bd4e404 52 * the host starting every bus transaction by asserting the CS signal low. The
jjmedina 0:a5367bd4e404 53 * card always responds to commands, data blocks and errors.
jjmedina 0:a5367bd4e404 54 *
jjmedina 0:a5367bd4e404 55 * The protocol supports a CRC, but by default it is off (except for the
jjmedina 0:a5367bd4e404 56 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
jjmedina 0:a5367bd4e404 57 * I'll leave the CRC off I think!
jjmedina 0:a5367bd4e404 58 *
jjmedina 0:a5367bd4e404 59 * Standard capacity cards have variable data block sizes, whereas High
jjmedina 0:a5367bd4e404 60 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
jjmedina 0:a5367bd4e404 61 * just always use the Standard Capacity cards with a block size of 512 bytes.
jjmedina 0:a5367bd4e404 62 * This is set with CMD16.
jjmedina 0:a5367bd4e404 63 *
jjmedina 0:a5367bd4e404 64 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
jjmedina 0:a5367bd4e404 65 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
jjmedina 0:a5367bd4e404 66 * the card gets a read command, it responds with a response token, and then
jjmedina 0:a5367bd4e404 67 * a data token or an error.
jjmedina 0:a5367bd4e404 68 *
jjmedina 0:a5367bd4e404 69 * SPI Command Format
jjmedina 0:a5367bd4e404 70 * ------------------
jjmedina 0:a5367bd4e404 71 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
jjmedina 0:a5367bd4e404 72 *
jjmedina 0:a5367bd4e404 73 * +---------------+------------+------------+-----------+----------+--------------+
jjmedina 0:a5367bd4e404 74 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
jjmedina 0:a5367bd4e404 75 * +---------------+------------+------------+-----------+----------+--------------+
jjmedina 0:a5367bd4e404 76 *
jjmedina 0:a5367bd4e404 77 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
jjmedina 0:a5367bd4e404 78 *
jjmedina 0:a5367bd4e404 79 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
jjmedina 0:a5367bd4e404 80 *
jjmedina 0:a5367bd4e404 81 * SPI Response Format
jjmedina 0:a5367bd4e404 82 * -------------------
jjmedina 0:a5367bd4e404 83 * The main response format (R1) is a status byte (normally zero). Key flags:
jjmedina 0:a5367bd4e404 84 * idle - 1 if the card is in an idle state/initialising
jjmedina 0:a5367bd4e404 85 * cmd - 1 if an illegal command code was detected
jjmedina 0:a5367bd4e404 86 *
jjmedina 0:a5367bd4e404 87 * +-------------------------------------------------+
jjmedina 0:a5367bd4e404 88 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
jjmedina 0:a5367bd4e404 89 * +-------------------------------------------------+
jjmedina 0:a5367bd4e404 90 *
jjmedina 0:a5367bd4e404 91 * R1b is the same, except it is followed by a busy signal (zeros) until
jjmedina 0:a5367bd4e404 92 * the first non-zero byte when it is ready again.
jjmedina 0:a5367bd4e404 93 *
jjmedina 0:a5367bd4e404 94 * Data Response Token
jjmedina 0:a5367bd4e404 95 * -------------------
jjmedina 0:a5367bd4e404 96 * Every data block written to the card is acknowledged by a byte
jjmedina 0:a5367bd4e404 97 * response token
jjmedina 0:a5367bd4e404 98 *
jjmedina 0:a5367bd4e404 99 * +----------------------+
jjmedina 0:a5367bd4e404 100 * | xxx | 0 | status | 1 |
jjmedina 0:a5367bd4e404 101 * +----------------------+
jjmedina 0:a5367bd4e404 102 * 010 - OK!
jjmedina 0:a5367bd4e404 103 * 101 - CRC Error
jjmedina 0:a5367bd4e404 104 * 110 - Write Error
jjmedina 0:a5367bd4e404 105 *
jjmedina 0:a5367bd4e404 106 * Single Block Read and Write
jjmedina 0:a5367bd4e404 107 * ---------------------------
jjmedina 0:a5367bd4e404 108 *
jjmedina 0:a5367bd4e404 109 * Block transfers have a byte header, followed by the data, followed
jjmedina 0:a5367bd4e404 110 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
jjmedina 0:a5367bd4e404 111 *
jjmedina 0:a5367bd4e404 112 * +------+---------+---------+- - - -+---------+-----------+----------+
jjmedina 0:a5367bd4e404 113 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
jjmedina 0:a5367bd4e404 114 * +------+---------+---------+- - - -+---------+-----------+----------+
jjmedina 0:a5367bd4e404 115 */
jjmedina 0:a5367bd4e404 116
jjmedina 0:a5367bd4e404 117 #include "SDFileSystem.h"
jjmedina 0:a5367bd4e404 118
jjmedina 0:a5367bd4e404 119 #define SD_COMMAND_TIMEOUT 5000
jjmedina 0:a5367bd4e404 120
jjmedina 0:a5367bd4e404 121 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
jjmedina 0:a5367bd4e404 122 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
jjmedina 0:a5367bd4e404 123 _cs = 1;
jjmedina 0:a5367bd4e404 124 }
jjmedina 0:a5367bd4e404 125
jjmedina 0:a5367bd4e404 126 #define R1_IDLE_STATE (1 << 0)
jjmedina 0:a5367bd4e404 127 #define R1_ERASE_RESET (1 << 1)
jjmedina 0:a5367bd4e404 128 #define R1_ILLEGAL_COMMAND (1 << 2)
jjmedina 0:a5367bd4e404 129 #define R1_COM_CRC_ERROR (1 << 3)
jjmedina 0:a5367bd4e404 130 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
jjmedina 0:a5367bd4e404 131 #define R1_ADDRESS_ERROR (1 << 5)
jjmedina 0:a5367bd4e404 132 #define R1_PARAMETER_ERROR (1 << 6)
jjmedina 0:a5367bd4e404 133
jjmedina 0:a5367bd4e404 134 // Types
jjmedina 0:a5367bd4e404 135 // - v1.x Standard Capacity
jjmedina 0:a5367bd4e404 136 // - v2.x Standard Capacity
jjmedina 0:a5367bd4e404 137 // - v2.x High Capacity
jjmedina 0:a5367bd4e404 138 // - Not recognised as an SD Card
jjmedina 0:a5367bd4e404 139
jjmedina 0:a5367bd4e404 140 #define SDCARD_FAIL 0
jjmedina 0:a5367bd4e404 141 #define SDCARD_V1 1
jjmedina 0:a5367bd4e404 142 #define SDCARD_V2 2
jjmedina 0:a5367bd4e404 143 #define SDCARD_V2HC 3
jjmedina 0:a5367bd4e404 144
jjmedina 0:a5367bd4e404 145 int SDFileSystem::initialise_card() {
jjmedina 0:a5367bd4e404 146 // Set to 100kHz for initialisation, and clock card with cs = 1
jjmedina 0:a5367bd4e404 147 _spi.frequency(100000);
jjmedina 0:a5367bd4e404 148 _cs = 1;
jjmedina 0:a5367bd4e404 149 for(int i=0; i<16; i++) {
jjmedina 0:a5367bd4e404 150 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 151 }
jjmedina 0:a5367bd4e404 152
jjmedina 0:a5367bd4e404 153 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
jjmedina 0:a5367bd4e404 154 if(_cmd(0, 0) != R1_IDLE_STATE) {
jjmedina 0:a5367bd4e404 155 fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
jjmedina 0:a5367bd4e404 156 return SDCARD_FAIL;
jjmedina 0:a5367bd4e404 157 }
jjmedina 0:a5367bd4e404 158
jjmedina 0:a5367bd4e404 159 // send CMD8 to determine whther it is ver 2.x
jjmedina 0:a5367bd4e404 160 int r = _cmd8();
jjmedina 0:a5367bd4e404 161 if(r == R1_IDLE_STATE) {
jjmedina 0:a5367bd4e404 162 return initialise_card_v2();
jjmedina 0:a5367bd4e404 163 } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
jjmedina 0:a5367bd4e404 164 return initialise_card_v1();
jjmedina 0:a5367bd4e404 165 } else {
jjmedina 0:a5367bd4e404 166 fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
jjmedina 0:a5367bd4e404 167 return SDCARD_FAIL;
jjmedina 0:a5367bd4e404 168 }
jjmedina 0:a5367bd4e404 169 }
jjmedina 0:a5367bd4e404 170
jjmedina 0:a5367bd4e404 171 int SDFileSystem::initialise_card_v1() {
jjmedina 0:a5367bd4e404 172 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
jjmedina 0:a5367bd4e404 173 _cmd(55, 0);
jjmedina 0:a5367bd4e404 174 if(_cmd(41, 0) == 0) {
jjmedina 0:a5367bd4e404 175 return SDCARD_V1;
jjmedina 0:a5367bd4e404 176 }
jjmedina 0:a5367bd4e404 177 }
jjmedina 0:a5367bd4e404 178
jjmedina 0:a5367bd4e404 179 fprintf(stderr, "Timeout waiting for v1.x card\n");
jjmedina 0:a5367bd4e404 180 return SDCARD_FAIL;
jjmedina 0:a5367bd4e404 181 }
jjmedina 0:a5367bd4e404 182
jjmedina 0:a5367bd4e404 183 int SDFileSystem::initialise_card_v2() {
jjmedina 0:a5367bd4e404 184
jjmedina 0:a5367bd4e404 185 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
jjmedina 0:a5367bd4e404 186 _cmd(55, 0);
jjmedina 0:a5367bd4e404 187 if(_cmd(41, 0) == 0) {
jjmedina 0:a5367bd4e404 188 _cmd58();
jjmedina 0:a5367bd4e404 189 return SDCARD_V2;
jjmedina 0:a5367bd4e404 190 }
jjmedina 0:a5367bd4e404 191 }
jjmedina 0:a5367bd4e404 192
jjmedina 0:a5367bd4e404 193 fprintf(stderr, "Timeout waiting for v2.x card\n");
jjmedina 0:a5367bd4e404 194 return SDCARD_FAIL;
jjmedina 0:a5367bd4e404 195 }
jjmedina 0:a5367bd4e404 196
jjmedina 0:a5367bd4e404 197 int SDFileSystem::disk_initialize() {
jjmedina 0:a5367bd4e404 198
jjmedina 0:a5367bd4e404 199 int i = initialise_card();
jjmedina 0:a5367bd4e404 200 // printf("init card = %d\n", i);
jjmedina 0:a5367bd4e404 201 // printf("OK\n");
jjmedina 0:a5367bd4e404 202
jjmedina 0:a5367bd4e404 203 _sectors = _sd_sectors();
jjmedina 0:a5367bd4e404 204
jjmedina 0:a5367bd4e404 205 // Set block length to 512 (CMD16)
jjmedina 0:a5367bd4e404 206 if(_cmd(16, 512) != 0) {
jjmedina 0:a5367bd4e404 207 fprintf(stderr, "Set 512-byte block timed out\n");
jjmedina 0:a5367bd4e404 208 return 1;
jjmedina 0:a5367bd4e404 209 }
jjmedina 0:a5367bd4e404 210
jjmedina 0:a5367bd4e404 211 _spi.frequency(1000000); // Set to 1MHz for data transfer
jjmedina 0:a5367bd4e404 212 return 0;
jjmedina 0:a5367bd4e404 213 }
jjmedina 0:a5367bd4e404 214
jjmedina 0:a5367bd4e404 215 int SDFileSystem::disk_write(const char *buffer, int block_number) {
jjmedina 0:a5367bd4e404 216 // set write address for single block (CMD24)
jjmedina 0:a5367bd4e404 217 if(_cmd(24, block_number * 512) != 0) {
jjmedina 0:a5367bd4e404 218 return 1;
jjmedina 0:a5367bd4e404 219 }
jjmedina 0:a5367bd4e404 220
jjmedina 0:a5367bd4e404 221 // send the data block
jjmedina 0:a5367bd4e404 222 _write(buffer, 512);
jjmedina 0:a5367bd4e404 223 return 0;
jjmedina 0:a5367bd4e404 224 }
jjmedina 0:a5367bd4e404 225
jjmedina 0:a5367bd4e404 226 int SDFileSystem::disk_read(char *buffer, int block_number) {
jjmedina 0:a5367bd4e404 227 // set read address for single block (CMD17)
jjmedina 0:a5367bd4e404 228 if(_cmd(17, block_number * 512) != 0) {
jjmedina 0:a5367bd4e404 229 return 1;
jjmedina 0:a5367bd4e404 230 }
jjmedina 0:a5367bd4e404 231
jjmedina 0:a5367bd4e404 232 // receive the data
jjmedina 0:a5367bd4e404 233 _read(buffer, 512);
jjmedina 0:a5367bd4e404 234 return 0;
jjmedina 0:a5367bd4e404 235 }
jjmedina 0:a5367bd4e404 236
jjmedina 0:a5367bd4e404 237 int SDFileSystem::disk_status() { return 0; }
jjmedina 0:a5367bd4e404 238 int SDFileSystem::disk_sync() { return 0; }
jjmedina 0:a5367bd4e404 239 int SDFileSystem::disk_sectors() { return _sectors; }
jjmedina 0:a5367bd4e404 240
jjmedina 0:a5367bd4e404 241 // PRIVATE FUNCTIONS
jjmedina 0:a5367bd4e404 242
jjmedina 0:a5367bd4e404 243 int SDFileSystem::_cmd(int cmd, int arg) {
jjmedina 0:a5367bd4e404 244 _cs = 0;
jjmedina 0:a5367bd4e404 245
jjmedina 0:a5367bd4e404 246 // send a command
jjmedina 0:a5367bd4e404 247 _spi.write(0x40 | cmd);
jjmedina 0:a5367bd4e404 248 _spi.write(arg >> 24);
jjmedina 0:a5367bd4e404 249 _spi.write(arg >> 16);
jjmedina 0:a5367bd4e404 250 _spi.write(arg >> 8);
jjmedina 0:a5367bd4e404 251 _spi.write(arg >> 0);
jjmedina 0:a5367bd4e404 252 _spi.write(0x95);
jjmedina 0:a5367bd4e404 253
jjmedina 0:a5367bd4e404 254 // wait for the repsonse (response[7] == 0)
jjmedina 0:a5367bd4e404 255 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
jjmedina 0:a5367bd4e404 256 int response = _spi.write(0xFF);
jjmedina 0:a5367bd4e404 257 if(!(response & 0x80)) {
jjmedina 0:a5367bd4e404 258 _cs = 1;
jjmedina 0:a5367bd4e404 259 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 260 return response;
jjmedina 0:a5367bd4e404 261 }
jjmedina 0:a5367bd4e404 262 }
jjmedina 0:a5367bd4e404 263 _cs = 1;
jjmedina 0:a5367bd4e404 264 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 265 return -1; // timeout
jjmedina 0:a5367bd4e404 266 }
jjmedina 0:a5367bd4e404 267 int SDFileSystem::_cmdx(int cmd, int arg) {
jjmedina 0:a5367bd4e404 268 _cs = 0;
jjmedina 0:a5367bd4e404 269
jjmedina 0:a5367bd4e404 270 // send a command
jjmedina 0:a5367bd4e404 271 _spi.write(0x40 | cmd);
jjmedina 0:a5367bd4e404 272 _spi.write(arg >> 24);
jjmedina 0:a5367bd4e404 273 _spi.write(arg >> 16);
jjmedina 0:a5367bd4e404 274 _spi.write(arg >> 8);
jjmedina 0:a5367bd4e404 275 _spi.write(arg >> 0);
jjmedina 0:a5367bd4e404 276 _spi.write(0x95);
jjmedina 0:a5367bd4e404 277
jjmedina 0:a5367bd4e404 278 // wait for the repsonse (response[7] == 0)
jjmedina 0:a5367bd4e404 279 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
jjmedina 0:a5367bd4e404 280 int response = _spi.write(0xFF);
jjmedina 0:a5367bd4e404 281 if(!(response & 0x80)) {
jjmedina 0:a5367bd4e404 282 return response;
jjmedina 0:a5367bd4e404 283 }
jjmedina 0:a5367bd4e404 284 }
jjmedina 0:a5367bd4e404 285 _cs = 1;
jjmedina 0:a5367bd4e404 286 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 287 return -1; // timeout
jjmedina 0:a5367bd4e404 288 }
jjmedina 0:a5367bd4e404 289
jjmedina 0:a5367bd4e404 290
jjmedina 0:a5367bd4e404 291 int SDFileSystem::_cmd58() {
jjmedina 0:a5367bd4e404 292 _cs = 0;
jjmedina 0:a5367bd4e404 293 int arg = 0;
jjmedina 0:a5367bd4e404 294
jjmedina 0:a5367bd4e404 295 // send a command
jjmedina 0:a5367bd4e404 296 _spi.write(0x40 | 58);
jjmedina 0:a5367bd4e404 297 _spi.write(arg >> 24);
jjmedina 0:a5367bd4e404 298 _spi.write(arg >> 16);
jjmedina 0:a5367bd4e404 299 _spi.write(arg >> 8);
jjmedina 0:a5367bd4e404 300 _spi.write(arg >> 0);
jjmedina 0:a5367bd4e404 301 _spi.write(0x95);
jjmedina 0:a5367bd4e404 302
jjmedina 0:a5367bd4e404 303 // wait for the repsonse (response[7] == 0)
jjmedina 0:a5367bd4e404 304 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
jjmedina 0:a5367bd4e404 305 int response = _spi.write(0xFF);
jjmedina 0:a5367bd4e404 306 if(!(response & 0x80)) {
jjmedina 0:a5367bd4e404 307 int ocr = _spi.write(0xFF) << 24;
jjmedina 0:a5367bd4e404 308 ocr |= _spi.write(0xFF) << 16;
jjmedina 0:a5367bd4e404 309 ocr |= _spi.write(0xFF) << 8;
jjmedina 0:a5367bd4e404 310 ocr |= _spi.write(0xFF) << 0;
jjmedina 0:a5367bd4e404 311 // printf("OCR = 0x%08X\n", ocr);
jjmedina 0:a5367bd4e404 312 _cs = 1;
jjmedina 0:a5367bd4e404 313 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 314 return response;
jjmedina 0:a5367bd4e404 315 }
jjmedina 0:a5367bd4e404 316 }
jjmedina 0:a5367bd4e404 317 _cs = 1;
jjmedina 0:a5367bd4e404 318 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 319 return -1; // timeout
jjmedina 0:a5367bd4e404 320 }
jjmedina 0:a5367bd4e404 321
jjmedina 0:a5367bd4e404 322 int SDFileSystem::_cmd8() {
jjmedina 0:a5367bd4e404 323 _cs = 0;
jjmedina 0:a5367bd4e404 324
jjmedina 0:a5367bd4e404 325 // send a command
jjmedina 0:a5367bd4e404 326 _spi.write(0x40 | 8); // CMD8
jjmedina 0:a5367bd4e404 327 _spi.write(0x00); // reserved
jjmedina 0:a5367bd4e404 328 _spi.write(0x00); // reserved
jjmedina 0:a5367bd4e404 329 _spi.write(0x01); // 3.3v
jjmedina 0:a5367bd4e404 330 _spi.write(0xAA); // check pattern
jjmedina 0:a5367bd4e404 331 _spi.write(0x87); // crc
jjmedina 0:a5367bd4e404 332
jjmedina 0:a5367bd4e404 333 // wait for the repsonse (response[7] == 0)
jjmedina 0:a5367bd4e404 334 for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
jjmedina 0:a5367bd4e404 335 char response[5];
jjmedina 0:a5367bd4e404 336 response[0] = _spi.write(0xFF);
jjmedina 0:a5367bd4e404 337 if(!(response[0] & 0x80)) {
jjmedina 0:a5367bd4e404 338 for(int j=1; j<5; j++) {
jjmedina 0:a5367bd4e404 339 response[i] = _spi.write(0xFF);
jjmedina 0:a5367bd4e404 340 }
jjmedina 0:a5367bd4e404 341 _cs = 1;
jjmedina 0:a5367bd4e404 342 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 343 return response[0];
jjmedina 0:a5367bd4e404 344 }
jjmedina 0:a5367bd4e404 345 }
jjmedina 0:a5367bd4e404 346 _cs = 1;
jjmedina 0:a5367bd4e404 347 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 348 return -1; // timeout
jjmedina 0:a5367bd4e404 349 }
jjmedina 0:a5367bd4e404 350
jjmedina 0:a5367bd4e404 351 int SDFileSystem::_read(char *buffer, int length) {
jjmedina 0:a5367bd4e404 352 _cs = 0;
jjmedina 0:a5367bd4e404 353
jjmedina 0:a5367bd4e404 354 // read until start byte (0xFF)
jjmedina 0:a5367bd4e404 355 while(_spi.write(0xFF) != 0xFE);
jjmedina 0:a5367bd4e404 356
jjmedina 0:a5367bd4e404 357 // read data
jjmedina 0:a5367bd4e404 358 for(int i=0; i<length; i++) {
jjmedina 0:a5367bd4e404 359 buffer[i] = _spi.write(0xFF);
jjmedina 0:a5367bd4e404 360 }
jjmedina 0:a5367bd4e404 361 _spi.write(0xFF); // checksum
jjmedina 0:a5367bd4e404 362 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 363
jjmedina 0:a5367bd4e404 364 _cs = 1;
jjmedina 0:a5367bd4e404 365 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 366 return 0;
jjmedina 0:a5367bd4e404 367 }
jjmedina 0:a5367bd4e404 368
jjmedina 0:a5367bd4e404 369 int SDFileSystem::_write(const char *buffer, int length) {
jjmedina 0:a5367bd4e404 370 _cs = 0;
jjmedina 0:a5367bd4e404 371
jjmedina 0:a5367bd4e404 372 // indicate start of block
jjmedina 0:a5367bd4e404 373 _spi.write(0xFE);
jjmedina 0:a5367bd4e404 374
jjmedina 0:a5367bd4e404 375 // write the data
jjmedina 0:a5367bd4e404 376 for(int i=0; i<length; i++) {
jjmedina 0:a5367bd4e404 377 _spi.write(buffer[i]);
jjmedina 0:a5367bd4e404 378 }
jjmedina 0:a5367bd4e404 379
jjmedina 0:a5367bd4e404 380 // write the checksum
jjmedina 0:a5367bd4e404 381 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 382 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 383
jjmedina 0:a5367bd4e404 384 // check the repsonse token
jjmedina 0:a5367bd4e404 385 if((_spi.write(0xFF) & 0x1F) != 0x05) {
jjmedina 0:a5367bd4e404 386 _cs = 1;
jjmedina 0:a5367bd4e404 387 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 388 return 1;
jjmedina 0:a5367bd4e404 389 }
jjmedina 0:a5367bd4e404 390
jjmedina 0:a5367bd4e404 391 // wait for write to finish
jjmedina 0:a5367bd4e404 392 while(_spi.write(0xFF) == 0);
jjmedina 0:a5367bd4e404 393
jjmedina 0:a5367bd4e404 394 _cs = 1;
jjmedina 0:a5367bd4e404 395 _spi.write(0xFF);
jjmedina 0:a5367bd4e404 396 return 0;
jjmedina 0:a5367bd4e404 397 }
jjmedina 0:a5367bd4e404 398
jjmedina 0:a5367bd4e404 399 static int ext_bits(char *data, int msb, int lsb) {
jjmedina 0:a5367bd4e404 400 int bits = 0;
jjmedina 0:a5367bd4e404 401 int size = 1 + msb - lsb;
jjmedina 0:a5367bd4e404 402 for(int i=0; i<size; i++) {
jjmedina 0:a5367bd4e404 403 int position = lsb + i;
jjmedina 0:a5367bd4e404 404 int byte = 15 - (position >> 3);
jjmedina 0:a5367bd4e404 405 int bit = position & 0x7;
jjmedina 0:a5367bd4e404 406 int value = (data[byte] >> bit) & 1;
jjmedina 0:a5367bd4e404 407 bits |= value << i;
jjmedina 0:a5367bd4e404 408 }
jjmedina 0:a5367bd4e404 409 return bits;
jjmedina 0:a5367bd4e404 410 }
jjmedina 0:a5367bd4e404 411
jjmedina 0:a5367bd4e404 412 int SDFileSystem::_sd_sectors() {
jjmedina 0:a5367bd4e404 413
jjmedina 0:a5367bd4e404 414 // CMD9, Response R2 (R1 byte + 16-byte block read)
jjmedina 0:a5367bd4e404 415 if(_cmdx(9, 0) != 0) {
jjmedina 0:a5367bd4e404 416 fprintf(stderr, "Didn't get a response from the disk\n");
jjmedina 0:a5367bd4e404 417 return 0;
jjmedina 0:a5367bd4e404 418 }
jjmedina 0:a5367bd4e404 419
jjmedina 0:a5367bd4e404 420 char csd[16];
jjmedina 0:a5367bd4e404 421 if(_read(csd, 16) != 0) {
jjmedina 0:a5367bd4e404 422 fprintf(stderr, "Couldn't read csd response from disk\n");
jjmedina 0:a5367bd4e404 423 return 0;
jjmedina 0:a5367bd4e404 424 }
jjmedina 0:a5367bd4e404 425
jjmedina 0:a5367bd4e404 426 // csd_structure : csd[127:126]
jjmedina 0:a5367bd4e404 427 // c_size : csd[73:62]
jjmedina 0:a5367bd4e404 428 // c_size_mult : csd[49:47]
jjmedina 0:a5367bd4e404 429 // read_bl_len : csd[83:80] - the *maximum* read block length
jjmedina 0:a5367bd4e404 430
jjmedina 0:a5367bd4e404 431 int csd_structure = ext_bits(csd, 127, 126);
jjmedina 0:a5367bd4e404 432 int c_size = ext_bits(csd, 73, 62);
jjmedina 0:a5367bd4e404 433 int c_size_mult = ext_bits(csd, 49, 47);
jjmedina 0:a5367bd4e404 434 int read_bl_len = ext_bits(csd, 83, 80);
jjmedina 0:a5367bd4e404 435
jjmedina 0:a5367bd4e404 436 // printf("CSD_STRUCT = %d\n", csd_structure);
jjmedina 0:a5367bd4e404 437
jjmedina 0:a5367bd4e404 438 if(csd_structure != 0) {
jjmedina 0:a5367bd4e404 439 fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
jjmedina 0:a5367bd4e404 440 return 0;
jjmedina 0:a5367bd4e404 441 }
jjmedina 0:a5367bd4e404 442
jjmedina 0:a5367bd4e404 443 // memory capacity = BLOCKNR * BLOCK_LEN
jjmedina 0:a5367bd4e404 444 // where
jjmedina 0:a5367bd4e404 445 // BLOCKNR = (C_SIZE+1) * MULT
jjmedina 0:a5367bd4e404 446 // MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8)
jjmedina 0:a5367bd4e404 447 // BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12)
jjmedina 0:a5367bd4e404 448
jjmedina 0:a5367bd4e404 449 int block_len = 1 << read_bl_len;
jjmedina 0:a5367bd4e404 450 int mult = 1 << (c_size_mult + 2);
jjmedina 0:a5367bd4e404 451 int blocknr = (c_size + 1) * mult;
jjmedina 0:a5367bd4e404 452 int capacity = blocknr * block_len;
jjmedina 0:a5367bd4e404 453
jjmedina 0:a5367bd4e404 454 int blocks = capacity / 512;
jjmedina 0:a5367bd4e404 455
jjmedina 0:a5367bd4e404 456 return blocks;
jjmedina 0:a5367bd4e404 457 }