Nicholas Herriot / Mbed 2 deprecated ecu_reader

simple ecu reader

Dependencies:   FatFileSystem GPS-ecu TextLCD mbed

Fork of ecu_reader by Sukkin Pang

SDFileSystem.cpp@8:1ff6fb0d1fb6, 2014-02-25 (annotated)

Committer:
nherriot
Date:
Tue Feb 25 14:09:09 2014 +0000
Revision:
8:1ff6fb0d1fb6
Parent:
2:e7b3b8da71ff 
simple ecu reader

Who changed what in which revision?

UserRevisionLine numberNew contents of line
pangsk 2:e7b3b8da71ff 1 /* mbed SDFileSystem Library, for providing file access to SD cards
pangsk 2:e7b3b8da71ff 2 * Copyright (c) 2008-2010, sford
pangsk 2:e7b3b8da71ff 3 *
pangsk 2:e7b3b8da71ff 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
pangsk 2:e7b3b8da71ff 5 * of this software and associated documentation files (the "Software"), to deal
pangsk 2:e7b3b8da71ff 6 * in the Software without restriction, including without limitation the rights
pangsk 2:e7b3b8da71ff 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
pangsk 2:e7b3b8da71ff 8 * copies of the Software, and to permit persons to whom the Software is
pangsk 2:e7b3b8da71ff 9 * furnished to do so, subject to the following conditions:
pangsk 2:e7b3b8da71ff 10 *
pangsk 2:e7b3b8da71ff 11 * The above copyright notice and this permission notice shall be included in
pangsk 2:e7b3b8da71ff 12 * all copies or substantial portions of the Software.
pangsk 2:e7b3b8da71ff 13 *
pangsk 2:e7b3b8da71ff 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
pangsk 2:e7b3b8da71ff 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
pangsk 2:e7b3b8da71ff 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
pangsk 2:e7b3b8da71ff 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
pangsk 2:e7b3b8da71ff 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
pangsk 2:e7b3b8da71ff 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
pangsk 2:e7b3b8da71ff 20 * THE SOFTWARE.
pangsk 2:e7b3b8da71ff 21 */
pangsk 2:e7b3b8da71ff 22
pangsk 2:e7b3b8da71ff 23 /* Introduction
pangsk 2:e7b3b8da71ff 24 * ------------
pangsk 2:e7b3b8da71ff 25 * SD and MMC cards support a number of interfaces, but common to them all
pangsk 2:e7b3b8da71ff 26 * is one based on SPI. This is the one I'm implmenting because it means
pangsk 2:e7b3b8da71ff 27 * it is much more portable even though not so performant, and we already
pangsk 2:e7b3b8da71ff 28 * have the mbed SPI Interface!
pangsk 2:e7b3b8da71ff 29 *
pangsk 2:e7b3b8da71ff 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
pangsk 2:e7b3b8da71ff 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
pangsk 2:e7b3b8da71ff 32 *
pangsk 2:e7b3b8da71ff 33 * SPI Startup
pangsk 2:e7b3b8da71ff 34 * -----------
pangsk 2:e7b3b8da71ff 35 * The SD card powers up in SD mode. The SPI interface mode is selected by
pangsk 2:e7b3b8da71ff 36 * asserting CS low and sending the reset command (CMD0). The card will
pangsk 2:e7b3b8da71ff 37 * respond with a (R1) response.
pangsk 2:e7b3b8da71ff 38 *
pangsk 2:e7b3b8da71ff 39 * CMD8 is optionally sent to determine the voltage range supported, and
pangsk 2:e7b3b8da71ff 40 * indirectly determine whether it is a version 1.x SD/non-SD card or
pangsk 2:e7b3b8da71ff 41 * version 2.x. I'll just ignore this for now.
pangsk 2:e7b3b8da71ff 42 *
pangsk 2:e7b3b8da71ff 43 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
pangsk 2:e7b3b8da71ff 44 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
pangsk 2:e7b3b8da71ff 45 *
pangsk 2:e7b3b8da71ff 46 * You should also indicate whether the host supports High Capicity cards,
pangsk 2:e7b3b8da71ff 47 * and check whether the card is high capacity - i'll also ignore this
pangsk 2:e7b3b8da71ff 48 *
pangsk 2:e7b3b8da71ff 49 * SPI Protocol
pangsk 2:e7b3b8da71ff 50 * ------------
pangsk 2:e7b3b8da71ff 51 * The SD SPI protocol is based on transactions made up of 8-bit words, with
pangsk 2:e7b3b8da71ff 52 * the host starting every bus transaction by asserting the CS signal low. The
pangsk 2:e7b3b8da71ff 53 * card always responds to commands, data blocks and errors.
pangsk 2:e7b3b8da71ff 54 *
pangsk 2:e7b3b8da71ff 55 * The protocol supports a CRC, but by default it is off (except for the
pangsk 2:e7b3b8da71ff 56 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
pangsk 2:e7b3b8da71ff 57 * I'll leave the CRC off I think!
pangsk 2:e7b3b8da71ff 58 *
pangsk 2:e7b3b8da71ff 59 * Standard capacity cards have variable data block sizes, whereas High
pangsk 2:e7b3b8da71ff 60 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
pangsk 2:e7b3b8da71ff 61 * just always use the Standard Capacity cards with a block size of 512 bytes.
pangsk 2:e7b3b8da71ff 62 * This is set with CMD16.
pangsk 2:e7b3b8da71ff 63 *
pangsk 2:e7b3b8da71ff 64 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
pangsk 2:e7b3b8da71ff 65 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
pangsk 2:e7b3b8da71ff 66 * the card gets a read command, it responds with a response token, and then
pangsk 2:e7b3b8da71ff 67 * a data token or an error.
pangsk 2:e7b3b8da71ff 68 *
pangsk 2:e7b3b8da71ff 69 * SPI Command Format
pangsk 2:e7b3b8da71ff 70 * ------------------
pangsk 2:e7b3b8da71ff 71 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
pangsk 2:e7b3b8da71ff 72 *
pangsk 2:e7b3b8da71ff 73 * +---------------+------------+------------+-----------+----------+--------------+
pangsk 2:e7b3b8da71ff 74 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
pangsk 2:e7b3b8da71ff 75 * +---------------+------------+------------+-----------+----------+--------------+
pangsk 2:e7b3b8da71ff 76 *
pangsk 2:e7b3b8da71ff 77 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
pangsk 2:e7b3b8da71ff 78 *
pangsk 2:e7b3b8da71ff 79 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
pangsk 2:e7b3b8da71ff 80 *
pangsk 2:e7b3b8da71ff 81 * SPI Response Format
pangsk 2:e7b3b8da71ff 82 * -------------------
pangsk 2:e7b3b8da71ff 83 * The main response format (R1) is a status byte (normally zero). Key flags:
pangsk 2:e7b3b8da71ff 84 * idle - 1 if the card is in an idle state/initialising
pangsk 2:e7b3b8da71ff 85 * cmd - 1 if an illegal command code was detected
pangsk 2:e7b3b8da71ff 86 *
pangsk 2:e7b3b8da71ff 87 * +-------------------------------------------------+
pangsk 2:e7b3b8da71ff 88 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
pangsk 2:e7b3b8da71ff 89 * +-------------------------------------------------+
pangsk 2:e7b3b8da71ff 90 *
pangsk 2:e7b3b8da71ff 91 * R1b is the same, except it is followed by a busy signal (zeros) until
pangsk 2:e7b3b8da71ff 92 * the first non-zero byte when it is ready again.
pangsk 2:e7b3b8da71ff 93 *
pangsk 2:e7b3b8da71ff 94 * Data Response Token
pangsk 2:e7b3b8da71ff 95 * -------------------
pangsk 2:e7b3b8da71ff 96 * Every data block written to the card is acknowledged by a byte
pangsk 2:e7b3b8da71ff 97 * response token
pangsk 2:e7b3b8da71ff 98 *
pangsk 2:e7b3b8da71ff 99 * +----------------------+
pangsk 2:e7b3b8da71ff 100 * | xxx | 0 | status | 1 |
pangsk 2:e7b3b8da71ff 101 * +----------------------+
pangsk 2:e7b3b8da71ff 102 * 010 - OK!
pangsk 2:e7b3b8da71ff 103 * 101 - CRC Error
pangsk 2:e7b3b8da71ff 104 * 110 - Write Error
pangsk 2:e7b3b8da71ff 105 *
pangsk 2:e7b3b8da71ff 106 * Single Block Read and Write
pangsk 2:e7b3b8da71ff 107 * ---------------------------
pangsk 2:e7b3b8da71ff 108 *
pangsk 2:e7b3b8da71ff 109 * Block transfers have a byte header, followed by the data, followed
pangsk 2:e7b3b8da71ff 110 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
pangsk 2:e7b3b8da71ff 111 *
pangsk 2:e7b3b8da71ff 112 * +------+---------+---------+- - - -+---------+-----------+----------+
pangsk 2:e7b3b8da71ff 113 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
pangsk 2:e7b3b8da71ff 114 * +------+---------+---------+- - - -+---------+-----------+----------+
pangsk 2:e7b3b8da71ff 115 */
pangsk 2:e7b3b8da71ff 116
pangsk 2:e7b3b8da71ff 117 #include "SDFileSystem.h"
pangsk 2:e7b3b8da71ff 118
pangsk 2:e7b3b8da71ff 119 #define SD_COMMAND_TIMEOUT 5000
pangsk 2:e7b3b8da71ff 120
pangsk 2:e7b3b8da71ff 121 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
pangsk 2:e7b3b8da71ff 122 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
pangsk 2:e7b3b8da71ff 123 _cs = 1;
pangsk 2:e7b3b8da71ff 124 }
pangsk 2:e7b3b8da71ff 125
pangsk 2:e7b3b8da71ff 126 #define R1_IDLE_STATE (1 << 0)
pangsk 2:e7b3b8da71ff 127 #define R1_ERASE_RESET (1 << 1)
pangsk 2:e7b3b8da71ff 128 #define R1_ILLEGAL_COMMAND (1 << 2)
pangsk 2:e7b3b8da71ff 129 #define R1_COM_CRC_ERROR (1 << 3)
pangsk 2:e7b3b8da71ff 130 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
pangsk 2:e7b3b8da71ff 131 #define R1_ADDRESS_ERROR (1 << 5)
pangsk 2:e7b3b8da71ff 132 #define R1_PARAMETER_ERROR (1 << 6)
pangsk 2:e7b3b8da71ff 133
pangsk 2:e7b3b8da71ff 134 // Types
pangsk 2:e7b3b8da71ff 135 // - v1.x Standard Capacity
pangsk 2:e7b3b8da71ff 136 // - v2.x Standard Capacity
pangsk 2:e7b3b8da71ff 137 // - v2.x High Capacity
pangsk 2:e7b3b8da71ff 138 // - Not recognised as an SD Card
pangsk 2:e7b3b8da71ff 139
pangsk 2:e7b3b8da71ff 140 #define SDCARD_FAIL 0
pangsk 2:e7b3b8da71ff 141 #define SDCARD_V1 1
pangsk 2:e7b3b8da71ff 142 #define SDCARD_V2 2
pangsk 2:e7b3b8da71ff 143 #define SDCARD_V2HC 3
pangsk 2:e7b3b8da71ff 144
pangsk 2:e7b3b8da71ff 145 int SDFileSystem::initialise_card() {
pangsk 2:e7b3b8da71ff 146 // Set to 100kHz for initialisation, and clock card with cs = 1
pangsk 2:e7b3b8da71ff 147 _spi.frequency(100000);
pangsk 2:e7b3b8da71ff 148 _cs = 1;
pangsk 2:e7b3b8da71ff 149 for(int i=0; i<16; i++) {
pangsk 2:e7b3b8da71ff 150 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 151 }
pangsk 2:e7b3b8da71ff 152
pangsk 2:e7b3b8da71ff 153 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
pangsk 2:e7b3b8da71ff 154 if(_cmd(0, 0) != R1_IDLE_STATE) {
pangsk 2:e7b3b8da71ff 155 fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
pangsk 2:e7b3b8da71ff 156 return SDCARD_FAIL;
pangsk 2:e7b3b8da71ff 157 }
pangsk 2:e7b3b8da71ff 158
pangsk 2:e7b3b8da71ff 159 // send CMD8 to determine whther it is ver 2.x
pangsk 2:e7b3b8da71ff 160 int r = _cmd8();
pangsk 2:e7b3b8da71ff 161 if(r == R1_IDLE_STATE) {
pangsk 2:e7b3b8da71ff 162 return initialise_card_v2();
pangsk 2:e7b3b8da71ff 163 } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
pangsk 2:e7b3b8da71ff 164 return initialise_card_v1();
pangsk 2:e7b3b8da71ff 165 } else {
pangsk 2:e7b3b8da71ff 166 fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
pangsk 2:e7b3b8da71ff 167 return SDCARD_FAIL;
pangsk 2:e7b3b8da71ff 168 }
pangsk 2:e7b3b8da71ff 169 }
pangsk 2:e7b3b8da71ff 170
pangsk 2:e7b3b8da71ff 171 int SDFileSystem::initialise_card_v1() {
pangsk 2:e7b3b8da71ff 172 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
pangsk 2:e7b3b8da71ff 173 _cmd(55, 0);
pangsk 2:e7b3b8da71ff 174 if(_cmd(41, 0) == 0) {
pangsk 2:e7b3b8da71ff 175 return SDCARD_V1;
pangsk 2:e7b3b8da71ff 176 }
pangsk 2:e7b3b8da71ff 177 }
pangsk 2:e7b3b8da71ff 178
pangsk 2:e7b3b8da71ff 179 fprintf(stderr, "Timeout waiting for v1.x card\n");
pangsk 2:e7b3b8da71ff 180 return SDCARD_FAIL;
pangsk 2:e7b3b8da71ff 181 }
pangsk 2:e7b3b8da71ff 182
pangsk 2:e7b3b8da71ff 183 int SDFileSystem::initialise_card_v2() {
pangsk 2:e7b3b8da71ff 184
pangsk 2:e7b3b8da71ff 185 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
pangsk 2:e7b3b8da71ff 186 _cmd(55, 0);
pangsk 2:e7b3b8da71ff 187 if(_cmd(41, 0) == 0) {
pangsk 2:e7b3b8da71ff 188 _cmd58();
pangsk 2:e7b3b8da71ff 189 return SDCARD_V2;
pangsk 2:e7b3b8da71ff 190 }
pangsk 2:e7b3b8da71ff 191 }
pangsk 2:e7b3b8da71ff 192
pangsk 2:e7b3b8da71ff 193 fprintf(stderr, "Timeout waiting for v2.x card\n");
pangsk 2:e7b3b8da71ff 194 return SDCARD_FAIL;
pangsk 2:e7b3b8da71ff 195 }
pangsk 2:e7b3b8da71ff 196
pangsk 2:e7b3b8da71ff 197 int SDFileSystem::disk_initialize() {
pangsk 2:e7b3b8da71ff 198
pangsk 2:e7b3b8da71ff 199 int i = initialise_card();
pangsk 2:e7b3b8da71ff 200 // printf("init card = %d\n", i);
pangsk 2:e7b3b8da71ff 201 // printf("OK\n");
pangsk 2:e7b3b8da71ff 202
pangsk 2:e7b3b8da71ff 203 _sectors = _sd_sectors();
pangsk 2:e7b3b8da71ff 204
pangsk 2:e7b3b8da71ff 205 // Set block length to 512 (CMD16)
pangsk 2:e7b3b8da71ff 206 if(_cmd(16, 512) != 0) {
pangsk 2:e7b3b8da71ff 207 fprintf(stderr, "Set 512-byte block timed out\n");
pangsk 2:e7b3b8da71ff 208 return 1;
pangsk 2:e7b3b8da71ff 209 }
pangsk 2:e7b3b8da71ff 210
pangsk 2:e7b3b8da71ff 211 _spi.frequency(1000000); // Set to 1MHz for data transfer
pangsk 2:e7b3b8da71ff 212 return 0;
pangsk 2:e7b3b8da71ff 213 }
pangsk 2:e7b3b8da71ff 214
pangsk 2:e7b3b8da71ff 215 int SDFileSystem::disk_write(const char *buffer, int block_number) {
pangsk 2:e7b3b8da71ff 216 // set write address for single block (CMD24)
pangsk 2:e7b3b8da71ff 217 if(_cmd(24, block_number * 512) != 0) {
pangsk 2:e7b3b8da71ff 218 return 1;
pangsk 2:e7b3b8da71ff 219 }
pangsk 2:e7b3b8da71ff 220
pangsk 2:e7b3b8da71ff 221 // send the data block
pangsk 2:e7b3b8da71ff 222 _write(buffer, 512);
pangsk 2:e7b3b8da71ff 223 return 0;
pangsk 2:e7b3b8da71ff 224 }
pangsk 2:e7b3b8da71ff 225
pangsk 2:e7b3b8da71ff 226 int SDFileSystem::disk_read(char *buffer, int block_number) {
pangsk 2:e7b3b8da71ff 227 // set read address for single block (CMD17)
pangsk 2:e7b3b8da71ff 228 if(_cmd(17, block_number * 512) != 0) {
pangsk 2:e7b3b8da71ff 229 return 1;
pangsk 2:e7b3b8da71ff 230 }
pangsk 2:e7b3b8da71ff 231
pangsk 2:e7b3b8da71ff 232 // receive the data
pangsk 2:e7b3b8da71ff 233 _read(buffer, 512);
pangsk 2:e7b3b8da71ff 234 return 0;
pangsk 2:e7b3b8da71ff 235 }
pangsk 2:e7b3b8da71ff 236
pangsk 2:e7b3b8da71ff 237 int SDFileSystem::disk_status() { return 0; }
pangsk 2:e7b3b8da71ff 238 int SDFileSystem::disk_sync() { return 0; }
pangsk 2:e7b3b8da71ff 239 int SDFileSystem::disk_sectors() { return _sectors; }
pangsk 2:e7b3b8da71ff 240
pangsk 2:e7b3b8da71ff 241 // PRIVATE FUNCTIONS
pangsk 2:e7b3b8da71ff 242
pangsk 2:e7b3b8da71ff 243 int SDFileSystem::_cmd(int cmd, int arg) {
pangsk 2:e7b3b8da71ff 244 _cs = 0;
pangsk 2:e7b3b8da71ff 245
pangsk 2:e7b3b8da71ff 246 // send a command
pangsk 2:e7b3b8da71ff 247 _spi.write(0x40 | cmd);
pangsk 2:e7b3b8da71ff 248 _spi.write(arg >> 24);
pangsk 2:e7b3b8da71ff 249 _spi.write(arg >> 16);
pangsk 2:e7b3b8da71ff 250 _spi.write(arg >> 8);
pangsk 2:e7b3b8da71ff 251 _spi.write(arg >> 0);
pangsk 2:e7b3b8da71ff 252 _spi.write(0x95);
pangsk 2:e7b3b8da71ff 253
pangsk 2:e7b3b8da71ff 254 // wait for the repsonse (response[7] == 0)
pangsk 2:e7b3b8da71ff 255 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
pangsk 2:e7b3b8da71ff 256 int response = _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 257 if(!(response & 0x80)) {
pangsk 2:e7b3b8da71ff 258 _cs = 1;
pangsk 2:e7b3b8da71ff 259 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 260 return response;
pangsk 2:e7b3b8da71ff 261 }
pangsk 2:e7b3b8da71ff 262 }
pangsk 2:e7b3b8da71ff 263 _cs = 1;
pangsk 2:e7b3b8da71ff 264 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 265 return -1; // timeout
pangsk 2:e7b3b8da71ff 266 }
pangsk 2:e7b3b8da71ff 267 int SDFileSystem::_cmdx(int cmd, int arg) {
pangsk 2:e7b3b8da71ff 268 _cs = 0;
pangsk 2:e7b3b8da71ff 269
pangsk 2:e7b3b8da71ff 270 // send a command
pangsk 2:e7b3b8da71ff 271 _spi.write(0x40 | cmd);
pangsk 2:e7b3b8da71ff 272 _spi.write(arg >> 24);
pangsk 2:e7b3b8da71ff 273 _spi.write(arg >> 16);
pangsk 2:e7b3b8da71ff 274 _spi.write(arg >> 8);
pangsk 2:e7b3b8da71ff 275 _spi.write(arg >> 0);
pangsk 2:e7b3b8da71ff 276 _spi.write(0x95);
pangsk 2:e7b3b8da71ff 277
pangsk 2:e7b3b8da71ff 278 // wait for the repsonse (response[7] == 0)
pangsk 2:e7b3b8da71ff 279 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
pangsk 2:e7b3b8da71ff 280 int response = _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 281 if(!(response & 0x80)) {
pangsk 2:e7b3b8da71ff 282 return response;
pangsk 2:e7b3b8da71ff 283 }
pangsk 2:e7b3b8da71ff 284 }
pangsk 2:e7b3b8da71ff 285 _cs = 1;
pangsk 2:e7b3b8da71ff 286 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 287 return -1; // timeout
pangsk 2:e7b3b8da71ff 288 }
pangsk 2:e7b3b8da71ff 289
pangsk 2:e7b3b8da71ff 290
pangsk 2:e7b3b8da71ff 291 int SDFileSystem::_cmd58() {
pangsk 2:e7b3b8da71ff 292 _cs = 0;
pangsk 2:e7b3b8da71ff 293 int arg = 0;
pangsk 2:e7b3b8da71ff 294
pangsk 2:e7b3b8da71ff 295 // send a command
pangsk 2:e7b3b8da71ff 296 _spi.write(0x40 | 58);
pangsk 2:e7b3b8da71ff 297 _spi.write(arg >> 24);
pangsk 2:e7b3b8da71ff 298 _spi.write(arg >> 16);
pangsk 2:e7b3b8da71ff 299 _spi.write(arg >> 8);
pangsk 2:e7b3b8da71ff 300 _spi.write(arg >> 0);
pangsk 2:e7b3b8da71ff 301 _spi.write(0x95);
pangsk 2:e7b3b8da71ff 302
pangsk 2:e7b3b8da71ff 303 // wait for the repsonse (response[7] == 0)
pangsk 2:e7b3b8da71ff 304 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
pangsk 2:e7b3b8da71ff 305 int response = _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 306 if(!(response & 0x80)) {
pangsk 2:e7b3b8da71ff 307 int ocr = _spi.write(0xFF) << 24;
pangsk 2:e7b3b8da71ff 308 ocr |= _spi.write(0xFF) << 16;
pangsk 2:e7b3b8da71ff 309 ocr |= _spi.write(0xFF) << 8;
pangsk 2:e7b3b8da71ff 310 ocr |= _spi.write(0xFF) << 0;
pangsk 2:e7b3b8da71ff 311 // printf("OCR = 0x%08X\n", ocr);
pangsk 2:e7b3b8da71ff 312 _cs = 1;
pangsk 2:e7b3b8da71ff 313 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 314 return response;
pangsk 2:e7b3b8da71ff 315 }
pangsk 2:e7b3b8da71ff 316 }
pangsk 2:e7b3b8da71ff 317 _cs = 1;
pangsk 2:e7b3b8da71ff 318 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 319 return -1; // timeout
pangsk 2:e7b3b8da71ff 320 }
pangsk 2:e7b3b8da71ff 321
pangsk 2:e7b3b8da71ff 322 int SDFileSystem::_cmd8() {
pangsk 2:e7b3b8da71ff 323 _cs = 0;
pangsk 2:e7b3b8da71ff 324
pangsk 2:e7b3b8da71ff 325 // send a command
pangsk 2:e7b3b8da71ff 326 _spi.write(0x40 | 8); // CMD8
pangsk 2:e7b3b8da71ff 327 _spi.write(0x00); // reserved
pangsk 2:e7b3b8da71ff 328 _spi.write(0x00); // reserved
pangsk 2:e7b3b8da71ff 329 _spi.write(0x01); // 3.3v
pangsk 2:e7b3b8da71ff 330 _spi.write(0xAA); // check pattern
pangsk 2:e7b3b8da71ff 331 _spi.write(0x87); // crc
pangsk 2:e7b3b8da71ff 332
pangsk 2:e7b3b8da71ff 333 // wait for the repsonse (response[7] == 0)
pangsk 2:e7b3b8da71ff 334 for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
pangsk 2:e7b3b8da71ff 335 char response[5];
pangsk 2:e7b3b8da71ff 336 response[0] = _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 337 if(!(response[0] & 0x80)) {
pangsk 2:e7b3b8da71ff 338 for(int j=1; j<5; j++) {
pangsk 2:e7b3b8da71ff 339 response[i] = _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 340 }
pangsk 2:e7b3b8da71ff 341 _cs = 1;
pangsk 2:e7b3b8da71ff 342 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 343 return response[0];
pangsk 2:e7b3b8da71ff 344 }
pangsk 2:e7b3b8da71ff 345 }
pangsk 2:e7b3b8da71ff 346 _cs = 1;
pangsk 2:e7b3b8da71ff 347 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 348 return -1; // timeout
pangsk 2:e7b3b8da71ff 349 }
pangsk 2:e7b3b8da71ff 350
pangsk 2:e7b3b8da71ff 351 int SDFileSystem::_read(char *buffer, int length) {
pangsk 2:e7b3b8da71ff 352 _cs = 0;
pangsk 2:e7b3b8da71ff 353
pangsk 2:e7b3b8da71ff 354 // read until start byte (0xFF)
pangsk 2:e7b3b8da71ff 355 while(_spi.write(0xFF) != 0xFE);
pangsk 2:e7b3b8da71ff 356
pangsk 2:e7b3b8da71ff 357 // read data
pangsk 2:e7b3b8da71ff 358 for(int i=0; i<length; i++) {
pangsk 2:e7b3b8da71ff 359 buffer[i] = _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 360 }
pangsk 2:e7b3b8da71ff 361 _spi.write(0xFF); // checksum
pangsk 2:e7b3b8da71ff 362 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 363
pangsk 2:e7b3b8da71ff 364 _cs = 1;
pangsk 2:e7b3b8da71ff 365 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 366 return 0;
pangsk 2:e7b3b8da71ff 367 }
pangsk 2:e7b3b8da71ff 368
pangsk 2:e7b3b8da71ff 369 int SDFileSystem::_write(const char *buffer, int length) {
pangsk 2:e7b3b8da71ff 370 _cs = 0;
pangsk 2:e7b3b8da71ff 371
pangsk 2:e7b3b8da71ff 372 // indicate start of block
pangsk 2:e7b3b8da71ff 373 _spi.write(0xFE);
pangsk 2:e7b3b8da71ff 374
pangsk 2:e7b3b8da71ff 375 // write the data
pangsk 2:e7b3b8da71ff 376 for(int i=0; i<length; i++) {
pangsk 2:e7b3b8da71ff 377 _spi.write(buffer[i]);
pangsk 2:e7b3b8da71ff 378 }
pangsk 2:e7b3b8da71ff 379
pangsk 2:e7b3b8da71ff 380 // write the checksum
pangsk 2:e7b3b8da71ff 381 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 382 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 383
pangsk 2:e7b3b8da71ff 384 // check the repsonse token
pangsk 2:e7b3b8da71ff 385 if((_spi.write(0xFF) & 0x1F) != 0x05) {
pangsk 2:e7b3b8da71ff 386 _cs = 1;
pangsk 2:e7b3b8da71ff 387 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 388 return 1;
pangsk 2:e7b3b8da71ff 389 }
pangsk 2:e7b3b8da71ff 390
pangsk 2:e7b3b8da71ff 391 // wait for write to finish
pangsk 2:e7b3b8da71ff 392 while(_spi.write(0xFF) == 0);
pangsk 2:e7b3b8da71ff 393
pangsk 2:e7b3b8da71ff 394 _cs = 1;
pangsk 2:e7b3b8da71ff 395 _spi.write(0xFF);
pangsk 2:e7b3b8da71ff 396 return 0;
pangsk 2:e7b3b8da71ff 397 }
pangsk 2:e7b3b8da71ff 398
pangsk 2:e7b3b8da71ff 399 static int ext_bits(char *data, int msb, int lsb) {
pangsk 2:e7b3b8da71ff 400 int bits = 0;
pangsk 2:e7b3b8da71ff 401 int size = 1 + msb - lsb;
pangsk 2:e7b3b8da71ff 402 for(int i=0; i<size; i++) {
pangsk 2:e7b3b8da71ff 403 int position = lsb + i;
pangsk 2:e7b3b8da71ff 404 int byte = 15 - (position >> 3);
pangsk 2:e7b3b8da71ff 405 int bit = position & 0x7;
pangsk 2:e7b3b8da71ff 406 int value = (data[byte] >> bit) & 1;
pangsk 2:e7b3b8da71ff 407 bits |= value << i;
pangsk 2:e7b3b8da71ff 408 }
pangsk 2:e7b3b8da71ff 409 return bits;
pangsk 2:e7b3b8da71ff 410 }
pangsk 2:e7b3b8da71ff 411
pangsk 2:e7b3b8da71ff 412 int SDFileSystem::_sd_sectors() {
pangsk 2:e7b3b8da71ff 413
pangsk 2:e7b3b8da71ff 414 // CMD9, Response R2 (R1 byte + 16-byte block read)
pangsk 2:e7b3b8da71ff 415 if(_cmdx(9, 0) != 0) {
pangsk 2:e7b3b8da71ff 416 fprintf(stderr, "Didn't get a response from the disk\n");
pangsk 2:e7b3b8da71ff 417 return 0;
pangsk 2:e7b3b8da71ff 418 }
pangsk 2:e7b3b8da71ff 419
pangsk 2:e7b3b8da71ff 420 char csd[16];
pangsk 2:e7b3b8da71ff 421 if(_read(csd, 16) != 0) {
pangsk 2:e7b3b8da71ff 422 fprintf(stderr, "Couldn't read csd response from disk\n");
pangsk 2:e7b3b8da71ff 423 return 0;
pangsk 2:e7b3b8da71ff 424 }
pangsk 2:e7b3b8da71ff 425
pangsk 2:e7b3b8da71ff 426 // csd_structure : csd[127:126]
pangsk 2:e7b3b8da71ff 427 // c_size : csd[73:62]
pangsk 2:e7b3b8da71ff 428 // c_size_mult : csd[49:47]
pangsk 2:e7b3b8da71ff 429 // read_bl_len : csd[83:80] - the *maximum* read block length
pangsk 2:e7b3b8da71ff 430
pangsk 2:e7b3b8da71ff 431 int csd_structure = ext_bits(csd, 127, 126);
pangsk 2:e7b3b8da71ff 432 int c_size = ext_bits(csd, 73, 62);
pangsk 2:e7b3b8da71ff 433 int c_size_mult = ext_bits(csd, 49, 47);
pangsk 2:e7b3b8da71ff 434 int read_bl_len = ext_bits(csd, 83, 80);
pangsk 2:e7b3b8da71ff 435
pangsk 2:e7b3b8da71ff 436 // printf("CSD_STRUCT = %d\n", csd_structure);
pangsk 2:e7b3b8da71ff 437
pangsk 2:e7b3b8da71ff 438 if(csd_structure != 0) {
pangsk 2:e7b3b8da71ff 439 fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
pangsk 2:e7b3b8da71ff 440 return 0;
pangsk 2:e7b3b8da71ff 441 }
pangsk 2:e7b3b8da71ff 442
pangsk 2:e7b3b8da71ff 443 // memory capacity = BLOCKNR * BLOCK_LEN
pangsk 2:e7b3b8da71ff 444 // where
pangsk 2:e7b3b8da71ff 445 // BLOCKNR = (C_SIZE+1) * MULT
pangsk 2:e7b3b8da71ff 446 // MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8)
pangsk 2:e7b3b8da71ff 447 // BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12)
pangsk 2:e7b3b8da71ff 448
pangsk 2:e7b3b8da71ff 449 int block_len = 1 << read_bl_len;
pangsk 2:e7b3b8da71ff 450 int mult = 1 << (c_size_mult + 2);
pangsk 2:e7b3b8da71ff 451 int blocknr = (c_size + 1) * mult;
pangsk 2:e7b3b8da71ff 452 int capacity = blocknr * block_len;
pangsk 2:e7b3b8da71ff 453
pangsk 2:e7b3b8da71ff 454 int blocks = capacity / 512;
pangsk 2:e7b3b8da71ff 455
pangsk 2:e7b3b8da71ff 456 return blocks;
pangsk 2:e7b3b8da71ff 457 }