J. Peterson / Mbed 2 deprecated CuriLightCtl

Source code for the Curilights Controller. See http://www.saccade.com/writing/projects/CuriController/ for details.

Dependencies:   FatFileSystem mbed

This is the source code for the Curilights controller. This lets you interactively control a string of Curilights. It provides a simple click-wheel user interface for changing colors, brightness and behavior. It responds to movement and lighting.

Finished Controller

/media/uploads/isonno/nxp3872_controllerclose.jpg

System Block Diagram

/media/uploads/isonno/blockdiagram.png

SDFileSystem.cpp@4:cfef06d8bb96, 2013-02-11 (annotated)

Committer:
isonno
Date:
Mon Feb 11 05:04:18 2013 +0000
Revision:
4:cfef06d8bb96
Parent:
0:6da5625a6946 
Minor changes to add backlight routines.  Not hooked up yet, shouldn't affect build operation.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
isonno 0:6da5625a6946 1 /* mbed SDFileSystem Library, for providing file access to SD cards
isonno 0:6da5625a6946 2 * Copyright (c) 2008-2010, sford
isonno 0:6da5625a6946 3 *
isonno 0:6da5625a6946 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
isonno 0:6da5625a6946 5 * of this software and associated documentation files (the "Software"), to deal
isonno 0:6da5625a6946 6 * in the Software without restriction, including without limitation the rights
isonno 0:6da5625a6946 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
isonno 0:6da5625a6946 8 * copies of the Software, and to permit persons to whom the Software is
isonno 0:6da5625a6946 9 * furnished to do so, subject to the following conditions:
isonno 0:6da5625a6946 10 *
isonno 0:6da5625a6946 11 * The above copyright notice and this permission notice shall be included in
isonno 0:6da5625a6946 12 * all copies or substantial portions of the Software.
isonno 0:6da5625a6946 13 *
isonno 0:6da5625a6946 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
isonno 0:6da5625a6946 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
isonno 0:6da5625a6946 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
isonno 0:6da5625a6946 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
isonno 0:6da5625a6946 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
isonno 0:6da5625a6946 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
isonno 0:6da5625a6946 20 * THE SOFTWARE.
isonno 0:6da5625a6946 21 */
isonno 0:6da5625a6946 22
isonno 0:6da5625a6946 23 /* Introduction
isonno 0:6da5625a6946 24 * ------------
isonno 0:6da5625a6946 25 * SD and MMC cards support a number of interfaces, but common to them all
isonno 0:6da5625a6946 26 * is one based on SPI. This is the one I'm implmenting because it means
isonno 0:6da5625a6946 27 * it is much more portable even though not so performant, and we already
isonno 0:6da5625a6946 28 * have the mbed SPI Interface!
isonno 0:6da5625a6946 29 *
isonno 0:6da5625a6946 30 * The main reference I'm using is Chapter 7, "SPI Mode" of:
isonno 0:6da5625a6946 31 * http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
isonno 0:6da5625a6946 32 *
isonno 0:6da5625a6946 33 * SPI Startup
isonno 0:6da5625a6946 34 * -----------
isonno 0:6da5625a6946 35 * The SD card powers up in SD mode. The SPI interface mode is selected by
isonno 0:6da5625a6946 36 * asserting CS low and sending the reset command (CMD0). The card will
isonno 0:6da5625a6946 37 * respond with a (R1) response.
isonno 0:6da5625a6946 38 *
isonno 0:6da5625a6946 39 * CMD8 is optionally sent to determine the voltage range supported, and
isonno 0:6da5625a6946 40 * indirectly determine whether it is a version 1.x SD/non-SD card or
isonno 0:6da5625a6946 41 * version 2.x. I'll just ignore this for now.
isonno 0:6da5625a6946 42 *
isonno 0:6da5625a6946 43 * ACMD41 is repeatedly issued to initialise the card, until "in idle"
isonno 0:6da5625a6946 44 * (bit 0) of the R1 response goes to '0', indicating it is initialised.
isonno 0:6da5625a6946 45 *
isonno 0:6da5625a6946 46 * You should also indicate whether the host supports High Capicity cards,
isonno 0:6da5625a6946 47 * and check whether the card is high capacity - i'll also ignore this
isonno 0:6da5625a6946 48 *
isonno 0:6da5625a6946 49 * SPI Protocol
isonno 0:6da5625a6946 50 * ------------
isonno 0:6da5625a6946 51 * The SD SPI protocol is based on transactions made up of 8-bit words, with
isonno 0:6da5625a6946 52 * the host starting every bus transaction by asserting the CS signal low. The
isonno 0:6da5625a6946 53 * card always responds to commands, data blocks and errors.
isonno 0:6da5625a6946 54 *
isonno 0:6da5625a6946 55 * The protocol supports a CRC, but by default it is off (except for the
isonno 0:6da5625a6946 56 * first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
isonno 0:6da5625a6946 57 * I'll leave the CRC off I think!
isonno 0:6da5625a6946 58 *
isonno 0:6da5625a6946 59 * Standard capacity cards have variable data block sizes, whereas High
isonno 0:6da5625a6946 60 * Capacity cards fix the size of data block to 512 bytes. I'll therefore
isonno 0:6da5625a6946 61 * just always use the Standard Capacity cards with a block size of 512 bytes.
isonno 0:6da5625a6946 62 * This is set with CMD16.
isonno 0:6da5625a6946 63 *
isonno 0:6da5625a6946 64 * You can read and write single blocks (CMD17, CMD25) or multiple blocks
isonno 0:6da5625a6946 65 * (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
isonno 0:6da5625a6946 66 * the card gets a read command, it responds with a response token, and then
isonno 0:6da5625a6946 67 * a data token or an error.
isonno 0:6da5625a6946 68 *
isonno 0:6da5625a6946 69 * SPI Command Format
isonno 0:6da5625a6946 70 * ------------------
isonno 0:6da5625a6946 71 * Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
isonno 0:6da5625a6946 72 *
isonno 0:6da5625a6946 73 * +---------------+------------+------------+-----------+----------+--------------+
isonno 0:6da5625a6946 74 * | 01 | cmd[5:0] | arg[31:24] | arg[23:16] | arg[15:8] | arg[7:0] | crc[6:0] | 1 |
isonno 0:6da5625a6946 75 * +---------------+------------+------------+-----------+----------+--------------+
isonno 0:6da5625a6946 76 *
isonno 0:6da5625a6946 77 * As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
isonno 0:6da5625a6946 78 *
isonno 0:6da5625a6946 79 * All Application Specific commands shall be preceded with APP_CMD (CMD55).
isonno 0:6da5625a6946 80 *
isonno 0:6da5625a6946 81 * SPI Response Format
isonno 0:6da5625a6946 82 * -------------------
isonno 0:6da5625a6946 83 * The main response format (R1) is a status byte (normally zero). Key flags:
isonno 0:6da5625a6946 84 * idle - 1 if the card is in an idle state/initialising
isonno 0:6da5625a6946 85 * cmd - 1 if an illegal command code was detected
isonno 0:6da5625a6946 86 *
isonno 0:6da5625a6946 87 * +-------------------------------------------------+
isonno 0:6da5625a6946 88 * R1 | 0 | arg | addr | seq | crc | cmd | erase | idle |
isonno 0:6da5625a6946 89 * +-------------------------------------------------+
isonno 0:6da5625a6946 90 *
isonno 0:6da5625a6946 91 * R1b is the same, except it is followed by a busy signal (zeros) until
isonno 0:6da5625a6946 92 * the first non-zero byte when it is ready again.
isonno 0:6da5625a6946 93 *
isonno 0:6da5625a6946 94 * Data Response Token
isonno 0:6da5625a6946 95 * -------------------
isonno 0:6da5625a6946 96 * Every data block written to the card is acknowledged by a byte
isonno 0:6da5625a6946 97 * response token
isonno 0:6da5625a6946 98 *
isonno 0:6da5625a6946 99 * +----------------------+
isonno 0:6da5625a6946 100 * | xxx | 0 | status | 1 |
isonno 0:6da5625a6946 101 * +----------------------+
isonno 0:6da5625a6946 102 * 010 - OK!
isonno 0:6da5625a6946 103 * 101 - CRC Error
isonno 0:6da5625a6946 104 * 110 - Write Error
isonno 0:6da5625a6946 105 *
isonno 0:6da5625a6946 106 * Single Block Read and Write
isonno 0:6da5625a6946 107 * ---------------------------
isonno 0:6da5625a6946 108 *
isonno 0:6da5625a6946 109 * Block transfers have a byte header, followed by the data, followed
isonno 0:6da5625a6946 110 * by a 16-bit CRC. In our case, the data will always be 512 bytes.
isonno 0:6da5625a6946 111 *
isonno 0:6da5625a6946 112 * +------+---------+---------+- - - -+---------+-----------+----------+
isonno 0:6da5625a6946 113 * | 0xFE | data[0] | data[1] | | data[n] | crc[15:8] | crc[7:0] |
isonno 0:6da5625a6946 114 * +------+---------+---------+- - - -+---------+-----------+----------+
isonno 0:6da5625a6946 115 */
isonno 0:6da5625a6946 116
isonno 0:6da5625a6946 117 #include "SDFileSystem.h"
isonno 0:6da5625a6946 118
isonno 0:6da5625a6946 119 #define SD_COMMAND_TIMEOUT 5000
isonno 0:6da5625a6946 120
isonno 0:6da5625a6946 121 SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
isonno 0:6da5625a6946 122 FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
isonno 0:6da5625a6946 123 _cs = 1;
isonno 0:6da5625a6946 124 }
isonno 0:6da5625a6946 125
isonno 0:6da5625a6946 126 #define R1_IDLE_STATE (1 << 0)
isonno 0:6da5625a6946 127 #define R1_ERASE_RESET (1 << 1)
isonno 0:6da5625a6946 128 #define R1_ILLEGAL_COMMAND (1 << 2)
isonno 0:6da5625a6946 129 #define R1_COM_CRC_ERROR (1 << 3)
isonno 0:6da5625a6946 130 #define R1_ERASE_SEQUENCE_ERROR (1 << 4)
isonno 0:6da5625a6946 131 #define R1_ADDRESS_ERROR (1 << 5)
isonno 0:6da5625a6946 132 #define R1_PARAMETER_ERROR (1 << 6)
isonno 0:6da5625a6946 133
isonno 0:6da5625a6946 134 // Types
isonno 0:6da5625a6946 135 // - v1.x Standard Capacity
isonno 0:6da5625a6946 136 // - v2.x Standard Capacity
isonno 0:6da5625a6946 137 // - v2.x High Capacity
isonno 0:6da5625a6946 138 // - Not recognised as an SD Card
isonno 0:6da5625a6946 139
isonno 0:6da5625a6946 140 #define SDCARD_FAIL 0
isonno 0:6da5625a6946 141 #define SDCARD_V1 1
isonno 0:6da5625a6946 142 #define SDCARD_V2 2
isonno 0:6da5625a6946 143 #define SDCARD_V2HC 3
isonno 0:6da5625a6946 144
isonno 0:6da5625a6946 145 int SDFileSystem::initialise_card() {
isonno 0:6da5625a6946 146 // Set to 100kHz for initialisation, and clock card with cs = 1
isonno 0:6da5625a6946 147 _spi.frequency(100000);
isonno 0:6da5625a6946 148 _cs = 1;
isonno 0:6da5625a6946 149 for(int i=0; i<16; i++) {
isonno 0:6da5625a6946 150 _spi.write(0xFF);
isonno 0:6da5625a6946 151 }
isonno 0:6da5625a6946 152
isonno 0:6da5625a6946 153 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
isonno 0:6da5625a6946 154 if(_cmd(0, 0) != R1_IDLE_STATE) {
isonno 0:6da5625a6946 155 fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
isonno 0:6da5625a6946 156 return SDCARD_FAIL;
isonno 0:6da5625a6946 157 }
isonno 0:6da5625a6946 158
isonno 0:6da5625a6946 159 // send CMD8 to determine whther it is ver 2.x
isonno 0:6da5625a6946 160 int r = _cmd8();
isonno 0:6da5625a6946 161 if(r == R1_IDLE_STATE) {
isonno 0:6da5625a6946 162 return initialise_card_v2();
isonno 0:6da5625a6946 163 } else if(r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
isonno 0:6da5625a6946 164 return initialise_card_v1();
isonno 0:6da5625a6946 165 } else {
isonno 0:6da5625a6946 166 fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
isonno 0:6da5625a6946 167 return SDCARD_FAIL;
isonno 0:6da5625a6946 168 }
isonno 0:6da5625a6946 169 }
isonno 0:6da5625a6946 170
isonno 0:6da5625a6946 171 int SDFileSystem::initialise_card_v1() {
isonno 0:6da5625a6946 172 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
isonno 0:6da5625a6946 173 _cmd(55, 0);
isonno 0:6da5625a6946 174 if(_cmd(41, 0) == 0) {
isonno 0:6da5625a6946 175 return SDCARD_V1;
isonno 0:6da5625a6946 176 }
isonno 0:6da5625a6946 177 }
isonno 0:6da5625a6946 178
isonno 0:6da5625a6946 179 fprintf(stderr, "Timeout waiting for v1.x card\n");
isonno 0:6da5625a6946 180 return SDCARD_FAIL;
isonno 0:6da5625a6946 181 }
isonno 0:6da5625a6946 182
isonno 0:6da5625a6946 183 int SDFileSystem::initialise_card_v2() {
isonno 0:6da5625a6946 184
isonno 0:6da5625a6946 185 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
isonno 0:6da5625a6946 186 _cmd(55, 0);
isonno 0:6da5625a6946 187 if(_cmd(41, 0) == 0) {
isonno 0:6da5625a6946 188 _cmd58();
isonno 0:6da5625a6946 189 return SDCARD_V2;
isonno 0:6da5625a6946 190 }
isonno 0:6da5625a6946 191 }
isonno 0:6da5625a6946 192
isonno 0:6da5625a6946 193 fprintf(stderr, "Timeout waiting for v2.x card\n");
isonno 0:6da5625a6946 194 return SDCARD_FAIL;
isonno 0:6da5625a6946 195 }
isonno 0:6da5625a6946 196
isonno 0:6da5625a6946 197 int SDFileSystem::disk_initialize() {
isonno 0:6da5625a6946 198
isonno 0:6da5625a6946 199 int i = initialise_card();
isonno 0:6da5625a6946 200 // printf("init card = %d\n", i);
isonno 0:6da5625a6946 201 // printf("OK\n");
isonno 0:6da5625a6946 202
isonno 0:6da5625a6946 203 _sectors = _sd_sectors();
isonno 0:6da5625a6946 204
isonno 0:6da5625a6946 205 // Set block length to 512 (CMD16)
isonno 0:6da5625a6946 206 if(_cmd(16, 512) != 0) {
isonno 0:6da5625a6946 207 fprintf(stderr, "Set 512-byte block timed out\n");
isonno 0:6da5625a6946 208 return 1;
isonno 0:6da5625a6946 209 }
isonno 0:6da5625a6946 210
isonno 0:6da5625a6946 211 _spi.frequency(1000000); // Set to 1MHz for data transfer
isonno 0:6da5625a6946 212 return 0;
isonno 0:6da5625a6946 213 }
isonno 0:6da5625a6946 214
isonno 0:6da5625a6946 215 int SDFileSystem::disk_write(const char *buffer, int block_number) {
isonno 0:6da5625a6946 216 // set write address for single block (CMD24)
isonno 0:6da5625a6946 217 if(_cmd(24, block_number * 512) != 0) {
isonno 0:6da5625a6946 218 return 1;
isonno 0:6da5625a6946 219 }
isonno 0:6da5625a6946 220
isonno 0:6da5625a6946 221 // send the data block
isonno 0:6da5625a6946 222 _write(buffer, 512);
isonno 0:6da5625a6946 223 return 0;
isonno 0:6da5625a6946 224 }
isonno 0:6da5625a6946 225
isonno 0:6da5625a6946 226 int SDFileSystem::disk_read(char *buffer, int block_number) {
isonno 0:6da5625a6946 227 // set read address for single block (CMD17)
isonno 0:6da5625a6946 228 if(_cmd(17, block_number * 512) != 0) {
isonno 0:6da5625a6946 229 return 1;
isonno 0:6da5625a6946 230 }
isonno 0:6da5625a6946 231
isonno 0:6da5625a6946 232 // receive the data
isonno 0:6da5625a6946 233 _read(buffer, 512);
isonno 0:6da5625a6946 234 return 0;
isonno 0:6da5625a6946 235 }
isonno 0:6da5625a6946 236
isonno 0:6da5625a6946 237 int SDFileSystem::disk_status() { return 0; }
isonno 0:6da5625a6946 238 int SDFileSystem::disk_sync() { return 0; }
isonno 0:6da5625a6946 239 int SDFileSystem::disk_sectors() { return _sectors; }
isonno 0:6da5625a6946 240
isonno 0:6da5625a6946 241 // PRIVATE FUNCTIONS
isonno 0:6da5625a6946 242
isonno 0:6da5625a6946 243 int SDFileSystem::_cmd(int cmd, int arg) {
isonno 0:6da5625a6946 244 _cs = 0;
isonno 0:6da5625a6946 245
isonno 0:6da5625a6946 246 // send a command
isonno 0:6da5625a6946 247 _spi.write(0x40 | cmd);
isonno 0:6da5625a6946 248 _spi.write(arg >> 24);
isonno 0:6da5625a6946 249 _spi.write(arg >> 16);
isonno 0:6da5625a6946 250 _spi.write(arg >> 8);
isonno 0:6da5625a6946 251 _spi.write(arg >> 0);
isonno 0:6da5625a6946 252 _spi.write(0x95);
isonno 0:6da5625a6946 253
isonno 0:6da5625a6946 254 // wait for the repsonse (response[7] == 0)
isonno 0:6da5625a6946 255 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
isonno 0:6da5625a6946 256 int response = _spi.write(0xFF);
isonno 0:6da5625a6946 257 if(!(response & 0x80)) {
isonno 0:6da5625a6946 258 _cs = 1;
isonno 0:6da5625a6946 259 _spi.write(0xFF);
isonno 0:6da5625a6946 260 return response;
isonno 0:6da5625a6946 261 }
isonno 0:6da5625a6946 262 }
isonno 0:6da5625a6946 263 _cs = 1;
isonno 0:6da5625a6946 264 _spi.write(0xFF);
isonno 0:6da5625a6946 265 return -1; // timeout
isonno 0:6da5625a6946 266 }
isonno 0:6da5625a6946 267 int SDFileSystem::_cmdx(int cmd, int arg) {
isonno 0:6da5625a6946 268 _cs = 0;
isonno 0:6da5625a6946 269
isonno 0:6da5625a6946 270 // send a command
isonno 0:6da5625a6946 271 _spi.write(0x40 | cmd);
isonno 0:6da5625a6946 272 _spi.write(arg >> 24);
isonno 0:6da5625a6946 273 _spi.write(arg >> 16);
isonno 0:6da5625a6946 274 _spi.write(arg >> 8);
isonno 0:6da5625a6946 275 _spi.write(arg >> 0);
isonno 0:6da5625a6946 276 _spi.write(0x95);
isonno 0:6da5625a6946 277
isonno 0:6da5625a6946 278 // wait for the repsonse (response[7] == 0)
isonno 0:6da5625a6946 279 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
isonno 0:6da5625a6946 280 int response = _spi.write(0xFF);
isonno 0:6da5625a6946 281 if(!(response & 0x80)) {
isonno 0:6da5625a6946 282 return response;
isonno 0:6da5625a6946 283 }
isonno 0:6da5625a6946 284 }
isonno 0:6da5625a6946 285 _cs = 1;
isonno 0:6da5625a6946 286 _spi.write(0xFF);
isonno 0:6da5625a6946 287 return -1; // timeout
isonno 0:6da5625a6946 288 }
isonno 0:6da5625a6946 289
isonno 0:6da5625a6946 290
isonno 0:6da5625a6946 291 int SDFileSystem::_cmd58() {
isonno 0:6da5625a6946 292 _cs = 0;
isonno 0:6da5625a6946 293 int arg = 0;
isonno 0:6da5625a6946 294
isonno 0:6da5625a6946 295 // send a command
isonno 0:6da5625a6946 296 _spi.write(0x40 | 58);
isonno 0:6da5625a6946 297 _spi.write(arg >> 24);
isonno 0:6da5625a6946 298 _spi.write(arg >> 16);
isonno 0:6da5625a6946 299 _spi.write(arg >> 8);
isonno 0:6da5625a6946 300 _spi.write(arg >> 0);
isonno 0:6da5625a6946 301 _spi.write(0x95);
isonno 0:6da5625a6946 302
isonno 0:6da5625a6946 303 // wait for the repsonse (response[7] == 0)
isonno 0:6da5625a6946 304 for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
isonno 0:6da5625a6946 305 int response = _spi.write(0xFF);
isonno 0:6da5625a6946 306 if(!(response & 0x80)) {
isonno 0:6da5625a6946 307 int ocr = _spi.write(0xFF) << 24;
isonno 0:6da5625a6946 308 ocr |= _spi.write(0xFF) << 16;
isonno 0:6da5625a6946 309 ocr |= _spi.write(0xFF) << 8;
isonno 0:6da5625a6946 310 ocr |= _spi.write(0xFF) << 0;
isonno 0:6da5625a6946 311 // printf("OCR = 0x%08X\n", ocr);
isonno 0:6da5625a6946 312 _cs = 1;
isonno 0:6da5625a6946 313 _spi.write(0xFF);
isonno 0:6da5625a6946 314 return response;
isonno 0:6da5625a6946 315 }
isonno 0:6da5625a6946 316 }
isonno 0:6da5625a6946 317 _cs = 1;
isonno 0:6da5625a6946 318 _spi.write(0xFF);
isonno 0:6da5625a6946 319 return -1; // timeout
isonno 0:6da5625a6946 320 }
isonno 0:6da5625a6946 321
isonno 0:6da5625a6946 322 int SDFileSystem::_cmd8() {
isonno 0:6da5625a6946 323 _cs = 0;
isonno 0:6da5625a6946 324
isonno 0:6da5625a6946 325 // send a command
isonno 0:6da5625a6946 326 _spi.write(0x40 | 8); // CMD8
isonno 0:6da5625a6946 327 _spi.write(0x00); // reserved
isonno 0:6da5625a6946 328 _spi.write(0x00); // reserved
isonno 0:6da5625a6946 329 _spi.write(0x01); // 3.3v
isonno 0:6da5625a6946 330 _spi.write(0xAA); // check pattern
isonno 0:6da5625a6946 331 _spi.write(0x87); // crc
isonno 0:6da5625a6946 332
isonno 0:6da5625a6946 333 // wait for the repsonse (response[7] == 0)
isonno 0:6da5625a6946 334 for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
isonno 0:6da5625a6946 335 char response[5];
isonno 0:6da5625a6946 336 response[0] = _spi.write(0xFF);
isonno 0:6da5625a6946 337 if(!(response[0] & 0x80)) {
isonno 0:6da5625a6946 338 for(int j=1; j<5; j++) {
isonno 0:6da5625a6946 339 response[i] = _spi.write(0xFF);
isonno 0:6da5625a6946 340 }
isonno 0:6da5625a6946 341 _cs = 1;
isonno 0:6da5625a6946 342 _spi.write(0xFF);
isonno 0:6da5625a6946 343 return response[0];
isonno 0:6da5625a6946 344 }
isonno 0:6da5625a6946 345 }
isonno 0:6da5625a6946 346 _cs = 1;
isonno 0:6da5625a6946 347 _spi.write(0xFF);
isonno 0:6da5625a6946 348 return -1; // timeout
isonno 0:6da5625a6946 349 }
isonno 0:6da5625a6946 350
isonno 0:6da5625a6946 351 int SDFileSystem::_read(char *buffer, int length) {
isonno 0:6da5625a6946 352 _cs = 0;
isonno 0:6da5625a6946 353
isonno 0:6da5625a6946 354 // read until start byte (0xFF)
isonno 0:6da5625a6946 355 while(_spi.write(0xFF) != 0xFE);
isonno 0:6da5625a6946 356
isonno 0:6da5625a6946 357 // read data
isonno 0:6da5625a6946 358 for(int i=0; i<length; i++) {
isonno 0:6da5625a6946 359 buffer[i] = _spi.write(0xFF);
isonno 0:6da5625a6946 360 }
isonno 0:6da5625a6946 361 _spi.write(0xFF); // checksum
isonno 0:6da5625a6946 362 _spi.write(0xFF);
isonno 0:6da5625a6946 363
isonno 0:6da5625a6946 364 _cs = 1;
isonno 0:6da5625a6946 365 _spi.write(0xFF);
isonno 0:6da5625a6946 366 return 0;
isonno 0:6da5625a6946 367 }
isonno 0:6da5625a6946 368
isonno 0:6da5625a6946 369 int SDFileSystem::_write(const char *buffer, int length) {
isonno 0:6da5625a6946 370 _cs = 0;
isonno 0:6da5625a6946 371
isonno 0:6da5625a6946 372 // indicate start of block
isonno 0:6da5625a6946 373 _spi.write(0xFE);
isonno 0:6da5625a6946 374
isonno 0:6da5625a6946 375 // write the data
isonno 0:6da5625a6946 376 for(int i=0; i<length; i++) {
isonno 0:6da5625a6946 377 _spi.write(buffer[i]);
isonno 0:6da5625a6946 378 }
isonno 0:6da5625a6946 379
isonno 0:6da5625a6946 380 // write the checksum
isonno 0:6da5625a6946 381 _spi.write(0xFF);
isonno 0:6da5625a6946 382 _spi.write(0xFF);
isonno 0:6da5625a6946 383
isonno 0:6da5625a6946 384 // check the repsonse token
isonno 0:6da5625a6946 385 if((_spi.write(0xFF) & 0x1F) != 0x05) {
isonno 0:6da5625a6946 386 _cs = 1;
isonno 0:6da5625a6946 387 _spi.write(0xFF);
isonno 0:6da5625a6946 388 return 1;
isonno 0:6da5625a6946 389 }
isonno 0:6da5625a6946 390
isonno 0:6da5625a6946 391 // wait for write to finish
isonno 0:6da5625a6946 392 while(_spi.write(0xFF) == 0);
isonno 0:6da5625a6946 393
isonno 0:6da5625a6946 394 _cs = 1;
isonno 0:6da5625a6946 395 _spi.write(0xFF);
isonno 0:6da5625a6946 396 return 0;
isonno 0:6da5625a6946 397 }
isonno 0:6da5625a6946 398
isonno 0:6da5625a6946 399 static int ext_bits(char *data, int msb, int lsb) {
isonno 0:6da5625a6946 400 int bits = 0;
isonno 0:6da5625a6946 401 int size = 1 + msb - lsb;
isonno 0:6da5625a6946 402 for(int i=0; i<size; i++) {
isonno 0:6da5625a6946 403 int position = lsb + i;
isonno 0:6da5625a6946 404 int byte = 15 - (position >> 3);
isonno 0:6da5625a6946 405 int bit = position & 0x7;
isonno 0:6da5625a6946 406 int value = (data[byte] >> bit) & 1;
isonno 0:6da5625a6946 407 bits |= value << i;
isonno 0:6da5625a6946 408 }
isonno 0:6da5625a6946 409 return bits;
isonno 0:6da5625a6946 410 }
isonno 0:6da5625a6946 411
isonno 0:6da5625a6946 412 int SDFileSystem::_sd_sectors() {
isonno 0:6da5625a6946 413
isonno 0:6da5625a6946 414 // CMD9, Response R2 (R1 byte + 16-byte block read)
isonno 0:6da5625a6946 415 if(_cmdx(9, 0) != 0) {
isonno 0:6da5625a6946 416 fprintf(stderr, "Didn't get a response from the disk\n");
isonno 0:6da5625a6946 417 return 0;
isonno 0:6da5625a6946 418 }
isonno 0:6da5625a6946 419
isonno 0:6da5625a6946 420 char csd[16];
isonno 0:6da5625a6946 421 if(_read(csd, 16) != 0) {
isonno 0:6da5625a6946 422 fprintf(stderr, "Couldn't read csd response from disk\n");
isonno 0:6da5625a6946 423 return 0;
isonno 0:6da5625a6946 424 }
isonno 0:6da5625a6946 425
isonno 0:6da5625a6946 426 // csd_structure : csd[127:126]
isonno 0:6da5625a6946 427 // c_size : csd[73:62]
isonno 0:6da5625a6946 428 // c_size_mult : csd[49:47]
isonno 0:6da5625a6946 429 // read_bl_len : csd[83:80] - the *maximum* read block length
isonno 0:6da5625a6946 430
isonno 0:6da5625a6946 431 int csd_structure = ext_bits(csd, 127, 126);
isonno 0:6da5625a6946 432 int c_size = ext_bits(csd, 73, 62);
isonno 0:6da5625a6946 433 int c_size_mult = ext_bits(csd, 49, 47);
isonno 0:6da5625a6946 434 int read_bl_len = ext_bits(csd, 83, 80);
isonno 0:6da5625a6946 435
isonno 0:6da5625a6946 436 // printf("CSD_STRUCT = %d\n", csd_structure);
isonno 0:6da5625a6946 437
isonno 0:6da5625a6946 438 if(csd_structure != 0) {
isonno 0:6da5625a6946 439 fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
isonno 0:6da5625a6946 440 return 0;
isonno 0:6da5625a6946 441 }
isonno 0:6da5625a6946 442
isonno 0:6da5625a6946 443 // memory capacity = BLOCKNR * BLOCK_LEN
isonno 0:6da5625a6946 444 // where
isonno 0:6da5625a6946 445 // BLOCKNR = (C_SIZE+1) * MULT
isonno 0:6da5625a6946 446 // MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8)
isonno 0:6da5625a6946 447 // BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12)
isonno 0:6da5625a6946 448
isonno 0:6da5625a6946 449 int block_len = 1 << read_bl_len;
isonno 0:6da5625a6946 450 int mult = 1 << (c_size_mult + 2);
isonno 0:6da5625a6946 451 int blocknr = (c_size + 1) * mult;
isonno 0:6da5625a6946 452 int capacity = blocknr * block_len;
isonno 0:6da5625a6946 453
isonno 0:6da5625a6946 454 int blocks = capacity / 512;
isonno 0:6da5625a6946 455
isonno 0:6da5625a6946 456 return blocks;
isonno 0:6da5625a6946 457 }