Pradeep Kotipalli / Mbed 2 deprecated TFOX_CDMS_VR_1_0_WORKING

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Dependencies:   mbed-rtos mbed

Fork of TFOX_CDMS_VR_1_0_WORKING by Team Fox

SDCard.cpp@0:d6e3d1e21484, 2015-06-15 (annotated)

Committer:
cholletisaik777
Date:
Mon Jun 15 12:16:59 2015 +0000
Revision:
0:d6e3d1e21484
Child:
2:4c79b3dfef31
CDMS-RTOSv0.1

Who changed what in which revision?

UserRevisionLine numberNew contents of line
cholletisaik777 0:d6e3d1e21484 1 #include "SDCard.h"
cholletisaik777 0:d6e3d1e21484 2 #include "func_head.h"
cholletisaik777 0:d6e3d1e21484 3
cholletisaik777 0:d6e3d1e21484 4 SPI spi_SD(PTD6, PTD7, PTD5); // mosi, miso, sclk
cholletisaik777 0:d6e3d1e21484 5 DigitalOut cs_SD(PTD2);
cholletisaik777 0:d6e3d1e21484 6
cholletisaik777 0:d6e3d1e21484 7 int count_bro;
cholletisaik777 0:d6e3d1e21484 8 int cdv;
cholletisaik777 0:d6e3d1e21484 9
cholletisaik777 0:d6e3d1e21484 10 uint64_t sectors;
cholletisaik777 0:d6e3d1e21484 11 int initialise_card() {
cholletisaik777 0:d6e3d1e21484 12 // Set to 100kHz for initialisation, and clock card with cs_SD = 1
cholletisaik777 0:d6e3d1e21484 13 spi_SD.frequency(100000);
cholletisaik777 0:d6e3d1e21484 14 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 15 for (int i = 0; i < 16; i++) {
cholletisaik777 0:d6e3d1e21484 16 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 17 }
cholletisaik777 0:d6e3d1e21484 18
cholletisaik777 0:d6e3d1e21484 19 // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
cholletisaik777 0:d6e3d1e21484 20 if (cmd(0, 0) != R1_IDLE_STATE) {
cholletisaik777 0:d6e3d1e21484 21 debug("No disk, or could not put SD card in to SPI idle state\r\n");
cholletisaik777 0:d6e3d1e21484 22 return SDCARD_FAIL;
cholletisaik777 0:d6e3d1e21484 23 }
cholletisaik777 0:d6e3d1e21484 24
cholletisaik777 0:d6e3d1e21484 25 // send CMD8 to determine whther it is ver 2.x
cholletisaik777 0:d6e3d1e21484 26 int r = cmd8();
cholletisaik777 0:d6e3d1e21484 27 if (r == R1_IDLE_STATE) {
cholletisaik777 0:d6e3d1e21484 28 printf("Entering v2 bro\r\n");
cholletisaik777 0:d6e3d1e21484 29 return initialise_card_v2();
cholletisaik777 0:d6e3d1e21484 30
cholletisaik777 0:d6e3d1e21484 31 } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
cholletisaik777 0:d6e3d1e21484 32 printf("Entering v1 bro\r\n");
cholletisaik777 0:d6e3d1e21484 33 return initialise_card_v1();
cholletisaik777 0:d6e3d1e21484 34
cholletisaik777 0:d6e3d1e21484 35 } else {
cholletisaik777 0:d6e3d1e21484 36 debug("Not in idle state after sending CMD8 (not an SD card?)\r\n");
cholletisaik777 0:d6e3d1e21484 37 return SDCARD_FAIL;
cholletisaik777 0:d6e3d1e21484 38 }
cholletisaik777 0:d6e3d1e21484 39 }
cholletisaik777 0:d6e3d1e21484 40
cholletisaik777 0:d6e3d1e21484 41 int initialise_card_v1() {
cholletisaik777 0:d6e3d1e21484 42 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cholletisaik777 0:d6e3d1e21484 43 cmd(55, 0);
cholletisaik777 0:d6e3d1e21484 44 if (cmd(41, 0) == 0) {
cholletisaik777 0:d6e3d1e21484 45 printf("Yuppie v1 successful\r\n");
cholletisaik777 0:d6e3d1e21484 46 cdv = 512;
cholletisaik777 0:d6e3d1e21484 47 debug_if(SD_DBG, "\r\n\rInit: SEDCARD_V1\r\n\r");
cholletisaik777 0:d6e3d1e21484 48
cholletisaik777 0:d6e3d1e21484 49 return SDCARD_V1;
cholletisaik777 0:d6e3d1e21484 50 }
cholletisaik777 0:d6e3d1e21484 51 }
cholletisaik777 0:d6e3d1e21484 52
cholletisaik777 0:d6e3d1e21484 53 debug("Timeout waiting for v1.x card\r\n");
cholletisaik777 0:d6e3d1e21484 54 return SDCARD_FAIL;
cholletisaik777 0:d6e3d1e21484 55 }
cholletisaik777 0:d6e3d1e21484 56
cholletisaik777 0:d6e3d1e21484 57
cholletisaik777 0:d6e3d1e21484 58 int initialise_card_v2() {
cholletisaik777 0:d6e3d1e21484 59 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cholletisaik777 0:d6e3d1e21484 60 wait_ms(50);
cholletisaik777 0:d6e3d1e21484 61 cmd58();
cholletisaik777 0:d6e3d1e21484 62 cmd(55, 0);
cholletisaik777 0:d6e3d1e21484 63 if (cmd(41, 0x40000000) == 0) {
cholletisaik777 0:d6e3d1e21484 64 printf("Yuppie,v2 successful\r\n");
cholletisaik777 0:d6e3d1e21484 65 cmd58();
cholletisaik777 0:d6e3d1e21484 66 debug_if(SD_DBG, "\r\n\rInit: SDCARD_V2\r\n\r");
cholletisaik777 0:d6e3d1e21484 67 cdv = 1;
cholletisaik777 0:d6e3d1e21484 68
cholletisaik777 0:d6e3d1e21484 69 return SDCARD_V2;
cholletisaik777 0:d6e3d1e21484 70 }
cholletisaik777 0:d6e3d1e21484 71 }
cholletisaik777 0:d6e3d1e21484 72
cholletisaik777 0:d6e3d1e21484 73 debug("Timeout waiting for v2.x card\r\n");
cholletisaik777 0:d6e3d1e21484 74 return SDCARD_FAIL;
cholletisaik777 0:d6e3d1e21484 75 }
cholletisaik777 0:d6e3d1e21484 76
cholletisaik777 0:d6e3d1e21484 77 int cmd(int cmd, int arg) {
cholletisaik777 0:d6e3d1e21484 78 cs_SD = 0;
cholletisaik777 0:d6e3d1e21484 79
cholletisaik777 0:d6e3d1e21484 80 // send a command
cholletisaik777 0:d6e3d1e21484 81 spi_SD.write(0x40 | cmd);
cholletisaik777 0:d6e3d1e21484 82 spi_SD.write(arg >> 24);
cholletisaik777 0:d6e3d1e21484 83 spi_SD.write(arg >> 16);
cholletisaik777 0:d6e3d1e21484 84 spi_SD.write(arg >> 8);
cholletisaik777 0:d6e3d1e21484 85 spi_SD.write(arg >> 0);
cholletisaik777 0:d6e3d1e21484 86 spi_SD.write(0x95);
cholletisaik777 0:d6e3d1e21484 87
cholletisaik777 0:d6e3d1e21484 88 // wait for the repsonse (response[7] == 0)
cholletisaik777 0:d6e3d1e21484 89 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cholletisaik777 0:d6e3d1e21484 90 int response = spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 91 if (!(response & 0x80)) {
cholletisaik777 0:d6e3d1e21484 92 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 93 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 94 return response;
cholletisaik777 0:d6e3d1e21484 95 }
cholletisaik777 0:d6e3d1e21484 96 }
cholletisaik777 0:d6e3d1e21484 97 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 98 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 99 return -1; // timeout
cholletisaik777 0:d6e3d1e21484 100 }
cholletisaik777 0:d6e3d1e21484 101
cholletisaik777 0:d6e3d1e21484 102
cholletisaik777 0:d6e3d1e21484 103 int cmd58() {
cholletisaik777 0:d6e3d1e21484 104 cs_SD = 0;
cholletisaik777 0:d6e3d1e21484 105 int arg = 0;
cholletisaik777 0:d6e3d1e21484 106
cholletisaik777 0:d6e3d1e21484 107 // send a command
cholletisaik777 0:d6e3d1e21484 108 spi_SD.write(0x40 | 58);
cholletisaik777 0:d6e3d1e21484 109 spi_SD.write(arg >> 24);
cholletisaik777 0:d6e3d1e21484 110 spi_SD.write(arg >> 16);
cholletisaik777 0:d6e3d1e21484 111 spi_SD.write(arg >> 8);
cholletisaik777 0:d6e3d1e21484 112 spi_SD.write(arg >> 0);
cholletisaik777 0:d6e3d1e21484 113 spi_SD.write(0x95);
cholletisaik777 0:d6e3d1e21484 114
cholletisaik777 0:d6e3d1e21484 115 // wait for the repsonse (response[7] == 0)
cholletisaik777 0:d6e3d1e21484 116 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cholletisaik777 0:d6e3d1e21484 117 int response = spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 118 if (!(response & 0x80)) {
cholletisaik777 0:d6e3d1e21484 119 int ocr = spi_SD.write(0xFF) << 24;
cholletisaik777 0:d6e3d1e21484 120 ocr |= spi_SD.write(0xFF) << 16;
cholletisaik777 0:d6e3d1e21484 121 ocr |= spi_SD.write(0xFF) << 8;
cholletisaik777 0:d6e3d1e21484 122 ocr |= spi_SD.write(0xFF) << 0;
cholletisaik777 0:d6e3d1e21484 123 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 124 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 125 return response;
cholletisaik777 0:d6e3d1e21484 126 }
cholletisaik777 0:d6e3d1e21484 127 }
cholletisaik777 0:d6e3d1e21484 128 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 129 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 130 return -1; // timeout
cholletisaik777 0:d6e3d1e21484 131 }
cholletisaik777 0:d6e3d1e21484 132
cholletisaik777 0:d6e3d1e21484 133
cholletisaik777 0:d6e3d1e21484 134 int cmd8() {
cholletisaik777 0:d6e3d1e21484 135 cs_SD = 0;
cholletisaik777 0:d6e3d1e21484 136
cholletisaik777 0:d6e3d1e21484 137 // send a command
cholletisaik777 0:d6e3d1e21484 138 spi_SD.write(0x40 | 8); // CMD8
cholletisaik777 0:d6e3d1e21484 139 spi_SD.write(0x00); // reserved
cholletisaik777 0:d6e3d1e21484 140 spi_SD.write(0x00); // reserved
cholletisaik777 0:d6e3d1e21484 141 spi_SD.write(0x01); // 3.3v
cholletisaik777 0:d6e3d1e21484 142 spi_SD.write(0xAA); // check pattern
cholletisaik777 0:d6e3d1e21484 143 spi_SD.write(0x87); // crc
cholletisaik777 0:d6e3d1e21484 144
cholletisaik777 0:d6e3d1e21484 145 // wait for the repsonse (response[7] == 0)
cholletisaik777 0:d6e3d1e21484 146 for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
cholletisaik777 0:d6e3d1e21484 147 char response[5];
cholletisaik777 0:d6e3d1e21484 148 response[0] = spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 149 if (!(response[0] & 0x80)) {
cholletisaik777 0:d6e3d1e21484 150 for (int j = 1; j < 5; j++) {
cholletisaik777 0:d6e3d1e21484 151 response[i] = spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 152 }
cholletisaik777 0:d6e3d1e21484 153 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 154 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 155 return response[0];
cholletisaik777 0:d6e3d1e21484 156 }
cholletisaik777 0:d6e3d1e21484 157 }
cholletisaik777 0:d6e3d1e21484 158 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 159 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 160 return -1; // timeout
cholletisaik777 0:d6e3d1e21484 161 }
cholletisaik777 0:d6e3d1e21484 162
cholletisaik777 0:d6e3d1e21484 163 uint64_t sd_sectors() {
cholletisaik777 0:d6e3d1e21484 164 uint32_t c_size, c_size_mult, read_bl_len;
cholletisaik777 0:d6e3d1e21484 165 uint32_t block_len, mult, blocknr, capacity;
cholletisaik777 0:d6e3d1e21484 166 uint32_t hc_c_size;
cholletisaik777 0:d6e3d1e21484 167 uint64_t blocks;
cholletisaik777 0:d6e3d1e21484 168
cholletisaik777 0:d6e3d1e21484 169 // CMD9, Response R2 (R1 byte + 16-byte block read)
cholletisaik777 0:d6e3d1e21484 170 if (cmdx(9, 0) != 0) {
cholletisaik777 0:d6e3d1e21484 171 debug("Didn't get a response from the disk\r\n");
cholletisaik777 0:d6e3d1e21484 172 return 0;
cholletisaik777 0:d6e3d1e21484 173 }
cholletisaik777 0:d6e3d1e21484 174
cholletisaik777 0:d6e3d1e21484 175 uint8_t csd[16];
cholletisaik777 0:d6e3d1e21484 176 if (read(csd, 16) != 0) {
cholletisaik777 0:d6e3d1e21484 177 debug("Couldn't read csd response from disk\r\n");
cholletisaik777 0:d6e3d1e21484 178 return 0;
cholletisaik777 0:d6e3d1e21484 179 }
cholletisaik777 0:d6e3d1e21484 180
cholletisaik777 0:d6e3d1e21484 181 // csd_structure : csd[127:126]
cholletisaik777 0:d6e3d1e21484 182 // c_size : csd[73:62]
cholletisaik777 0:d6e3d1e21484 183 // c_size_mult : csd[49:47]
cholletisaik777 0:d6e3d1e21484 184 // read_bl_len : csd[83:80] - the *maximum* read block length
cholletisaik777 0:d6e3d1e21484 185
cholletisaik777 0:d6e3d1e21484 186 int csd_structure = ext_bits(csd, 127, 126);
cholletisaik777 0:d6e3d1e21484 187
cholletisaik777 0:d6e3d1e21484 188 switch (csd_structure) {
cholletisaik777 0:d6e3d1e21484 189 case 0:
cholletisaik777 0:d6e3d1e21484 190 cdv = 512;
cholletisaik777 0:d6e3d1e21484 191 c_size = ext_bits(csd, 73, 62);
cholletisaik777 0:d6e3d1e21484 192 c_size_mult = ext_bits(csd, 49, 47);
cholletisaik777 0:d6e3d1e21484 193 read_bl_len = ext_bits(csd, 83, 80);
cholletisaik777 0:d6e3d1e21484 194
cholletisaik777 0:d6e3d1e21484 195 block_len = 1 << read_bl_len;
cholletisaik777 0:d6e3d1e21484 196 mult = 1 << (c_size_mult + 2);
cholletisaik777 0:d6e3d1e21484 197 blocknr = (c_size + 1) * mult;
cholletisaik777 0:d6e3d1e21484 198 capacity = blocknr * block_len;
cholletisaik777 0:d6e3d1e21484 199 blocks = capacity / 512;
cholletisaik777 0:d6e3d1e21484 200 debug_if(SD_DBG, "\r\n\rSDCard\r\n\rc_size: %d \r\n\rcapacity: %ld \r\n\rsectors: %lld\r\n\r", c_size, capacity, blocks);
cholletisaik777 0:d6e3d1e21484 201 break;
cholletisaik777 0:d6e3d1e21484 202
cholletisaik777 0:d6e3d1e21484 203 case 1:
cholletisaik777 0:d6e3d1e21484 204 cdv = 1;
cholletisaik777 0:d6e3d1e21484 205 hc_c_size = ext_bits(csd, 63, 48);
cholletisaik777 0:d6e3d1e21484 206 blocks = (hc_c_size+1)*1024;
cholletisaik777 0:d6e3d1e21484 207 debug_if(SD_DBG, "\r\n\rSDHC Card \r\n\rhc_c_size: %d\r\n\rcapacity: %lld \r\n\rsectors: %lld\r\n\r", hc_c_size, blocks*512, blocks);
cholletisaik777 0:d6e3d1e21484 208 break;
cholletisaik777 0:d6e3d1e21484 209
cholletisaik777 0:d6e3d1e21484 210 default:
cholletisaik777 0:d6e3d1e21484 211 debug("CSD struct unsupported\r\r\n");
cholletisaik777 0:d6e3d1e21484 212 return 0;
cholletisaik777 0:d6e3d1e21484 213 };
cholletisaik777 0:d6e3d1e21484 214 return blocks;
cholletisaik777 0:d6e3d1e21484 215 }
cholletisaik777 0:d6e3d1e21484 216
cholletisaik777 0:d6e3d1e21484 217 int cmdx(int cmd, int arg) {
cholletisaik777 0:d6e3d1e21484 218 cs_SD = 0;
cholletisaik777 0:d6e3d1e21484 219
cholletisaik777 0:d6e3d1e21484 220 // send a command
cholletisaik777 0:d6e3d1e21484 221 spi_SD.write(0x40 | cmd);
cholletisaik777 0:d6e3d1e21484 222 spi_SD.write(arg >> 24);
cholletisaik777 0:d6e3d1e21484 223 spi_SD.write(arg >> 16);
cholletisaik777 0:d6e3d1e21484 224 spi_SD.write(arg >> 8);
cholletisaik777 0:d6e3d1e21484 225 spi_SD.write(arg >> 0);
cholletisaik777 0:d6e3d1e21484 226 spi_SD.write(0x95);
cholletisaik777 0:d6e3d1e21484 227
cholletisaik777 0:d6e3d1e21484 228 // wait for the repsonse (response[7] == 0)
cholletisaik777 0:d6e3d1e21484 229 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
cholletisaik777 0:d6e3d1e21484 230 int response = spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 231 if (!(response & 0x80)) {
cholletisaik777 0:d6e3d1e21484 232 return response;
cholletisaik777 0:d6e3d1e21484 233 }
cholletisaik777 0:d6e3d1e21484 234 }
cholletisaik777 0:d6e3d1e21484 235 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 236 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 237 return -1; // timeout
cholletisaik777 0:d6e3d1e21484 238 }
cholletisaik777 0:d6e3d1e21484 239
cholletisaik777 0:d6e3d1e21484 240
cholletisaik777 0:d6e3d1e21484 241 int read(uint8_t *buffer, uint32_t length) {
cholletisaik777 0:d6e3d1e21484 242 cs_SD = 0;
cholletisaik777 0:d6e3d1e21484 243
cholletisaik777 0:d6e3d1e21484 244 // read until start byte (0xFF)
cholletisaik777 0:d6e3d1e21484 245 while (spi_SD.write(0xFF) != 0xFE);
cholletisaik777 0:d6e3d1e21484 246
cholletisaik777 0:d6e3d1e21484 247 // read data
cholletisaik777 0:d6e3d1e21484 248 for (int i = 0; i < length; i++) {
cholletisaik777 0:d6e3d1e21484 249 buffer[i] = spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 250 }
cholletisaik777 0:d6e3d1e21484 251 spi_SD.write(0xFF); // checksum
cholletisaik777 0:d6e3d1e21484 252 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 253
cholletisaik777 0:d6e3d1e21484 254 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 255 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 256 return 0;
cholletisaik777 0:d6e3d1e21484 257 }
cholletisaik777 0:d6e3d1e21484 258
cholletisaik777 0:d6e3d1e21484 259 static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
cholletisaik777 0:d6e3d1e21484 260 uint32_t bits = 0;
cholletisaik777 0:d6e3d1e21484 261 uint32_t size = 1 + msb - lsb;
cholletisaik777 0:d6e3d1e21484 262 for (int i = 0; i < size; i++) {
cholletisaik777 0:d6e3d1e21484 263 uint32_t position = lsb + i;
cholletisaik777 0:d6e3d1e21484 264 uint32_t byte = 15 - (position >> 3);
cholletisaik777 0:d6e3d1e21484 265 uint32_t bit = position & 0x7;
cholletisaik777 0:d6e3d1e21484 266 uint32_t value = (data[byte] >> bit) & 1;
cholletisaik777 0:d6e3d1e21484 267 bits |= value << i;
cholletisaik777 0:d6e3d1e21484 268 }
cholletisaik777 0:d6e3d1e21484 269 return bits;
cholletisaik777 0:d6e3d1e21484 270 }
cholletisaik777 0:d6e3d1e21484 271
cholletisaik777 0:d6e3d1e21484 272 int disk_initialize() {
cholletisaik777 0:d6e3d1e21484 273 int i = initialise_card();
cholletisaik777 0:d6e3d1e21484 274 debug_if(SD_DBG, "init card = %d\r\n", i);
cholletisaik777 0:d6e3d1e21484 275 sectors = sd_sectors();
cholletisaik777 0:d6e3d1e21484 276
cholletisaik777 0:d6e3d1e21484 277 // Set block length to 512 (CMD16)
cholletisaik777 0:d6e3d1e21484 278 if (cmd(16, 512) != 0) {
cholletisaik777 0:d6e3d1e21484 279 debug("Set 512-byte block timed out\r\n");
cholletisaik777 0:d6e3d1e21484 280 return 1;
cholletisaik777 0:d6e3d1e21484 281 }
cholletisaik777 0:d6e3d1e21484 282 else
cholletisaik777 0:d6e3d1e21484 283 {
cholletisaik777 0:d6e3d1e21484 284 printf("Hey,block init succesful\r\n");
cholletisaik777 0:d6e3d1e21484 285 }
cholletisaik777 0:d6e3d1e21484 286
cholletisaik777 0:d6e3d1e21484 287 spi_SD.frequency(1000000); // Set to 1MHz for data transfer
cholletisaik777 0:d6e3d1e21484 288 return 0;
cholletisaik777 0:d6e3d1e21484 289 }
cholletisaik777 0:d6e3d1e21484 290
cholletisaik777 0:d6e3d1e21484 291 int disk_write(const uint8_t *buffer, uint64_t block_number)
cholletisaik777 0:d6e3d1e21484 292
cholletisaik777 0:d6e3d1e21484 293 {
cholletisaik777 0:d6e3d1e21484 294 // set write address for single block (CMD24)
cholletisaik777 0:d6e3d1e21484 295 if (cmd(24, block_number * cdv) != 0) {
cholletisaik777 0:d6e3d1e21484 296 return 1;
cholletisaik777 0:d6e3d1e21484 297 }
cholletisaik777 0:d6e3d1e21484 298
cholletisaik777 0:d6e3d1e21484 299 // send the data block
cholletisaik777 0:d6e3d1e21484 300 write(buffer, 512);
cholletisaik777 0:d6e3d1e21484 301 printf("Written Successfully bro \r\n");
cholletisaik777 0:d6e3d1e21484 302 return 0;
cholletisaik777 0:d6e3d1e21484 303 }
cholletisaik777 0:d6e3d1e21484 304
cholletisaik777 0:d6e3d1e21484 305 int write(const uint8_t*buffer, uint32_t length) {
cholletisaik777 0:d6e3d1e21484 306 cs_SD = 0;
cholletisaik777 0:d6e3d1e21484 307
cholletisaik777 0:d6e3d1e21484 308 // indicate start of block
cholletisaik777 0:d6e3d1e21484 309 spi_SD.write(0xFE);
cholletisaik777 0:d6e3d1e21484 310
cholletisaik777 0:d6e3d1e21484 311 // write the data
cholletisaik777 0:d6e3d1e21484 312 for (int i = 0; i < length; i++) {
cholletisaik777 0:d6e3d1e21484 313 spi_SD.write(buffer[i]);
cholletisaik777 0:d6e3d1e21484 314 }
cholletisaik777 0:d6e3d1e21484 315
cholletisaik777 0:d6e3d1e21484 316 // write the checksum
cholletisaik777 0:d6e3d1e21484 317 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 318 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 319
cholletisaik777 0:d6e3d1e21484 320 // check the response token
cholletisaik777 0:d6e3d1e21484 321 if ((spi_SD.write(0xFF) & 0x1F) != 0x05) {
cholletisaik777 0:d6e3d1e21484 322 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 323 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 324 return 1;
cholletisaik777 0:d6e3d1e21484 325 }
cholletisaik777 0:d6e3d1e21484 326
cholletisaik777 0:d6e3d1e21484 327 // wait for write to finish
cholletisaik777 0:d6e3d1e21484 328 while (spi_SD.write(0xFF) == 0);
cholletisaik777 0:d6e3d1e21484 329
cholletisaik777 0:d6e3d1e21484 330 cs_SD = 1;
cholletisaik777 0:d6e3d1e21484 331 spi_SD.write(0xFF);
cholletisaik777 0:d6e3d1e21484 332 return 0;
cholletisaik777 0:d6e3d1e21484 333 }
cholletisaik777 0:d6e3d1e21484 334
cholletisaik777 0:d6e3d1e21484 335 int disk_read(uint8_t *buffer, uint64_t block_number) {
cholletisaik777 0:d6e3d1e21484 336 // set read address for single block (CMD17)
cholletisaik777 0:d6e3d1e21484 337 if (cmd(17, block_number * cdv) != 0) {
cholletisaik777 0:d6e3d1e21484 338 return 1;
cholletisaik777 0:d6e3d1e21484 339 }
cholletisaik777 0:d6e3d1e21484 340
cholletisaik777 0:d6e3d1e21484 341 // receive the data
cholletisaik777 0:d6e3d1e21484 342 read(buffer, 512);
cholletisaik777 0:d6e3d1e21484 343 return 0;
cholletisaik777 0:d6e3d1e21484 344 }