SDCard.cpp

00001 #include "SDCard.h"
00002 #include "func_head.h"
00003 
00004 SPI spi_SD(PTD6, PTD7, PTD5); // mosi, miso, sclk
00005 DigitalOut cs_SD(D2);
00006 
00007 int count_bro;
00008 int cdv;
00009 uint64_t sectors;
00010 
00011 int *FUNC_INIT_SD()
00012 {
00013     int sd_response[2] = {initialise_card(),disk_initialize()};
00014     return sd_response;    
00015 }
00016 
00017     
00018 int initialise_card() {
00019     // Set to 100kHz for initialisation, and clock card with cs_SD = 1
00020     spi_SD.frequency(100000);
00021     cs_SD = 1;
00022     for (int i = 0; i < 16; i++) {
00023         spi_SD.write(0xFF);
00024     }
00025     
00026     // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
00027     if (cmd(0, 0) != R1_IDLE_STATE) {
00028         debug("No disk, or could not put SD card in to SPI idle state\r\n");
00029         return SDCARD_FAIL;
00030     }
00031  
00032  // send CMD8 to determine whther it is ver 2.x
00033     int r = cmd8();
00034     if (r == R1_IDLE_STATE) {
00035         printf("Entering v2 bro\r\n");
00036         return initialise_card_v2();
00037         
00038     } else if (r == (R1_IDLE_STATE | R1_ILLEGAL_COMMAND)) {
00039         printf("Entering v1 bro\r\n");
00040         return initialise_card_v1();
00041         
00042     } else {
00043         debug("Not in idle state after sending CMD8 (not an SD card?)\r\n");
00044         return SDCARD_FAIL;
00045     }
00046 }
00047  
00048 int initialise_card_v1() {
00049     for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
00050         cmd(55, 0);
00051         if (cmd(41, 0) == 0) {
00052             printf("Yuppie v1 successful\r\n");
00053             cdv = 512;
00054             debug_if(SD_DBG, "\r\n\rInit: SEDCARD_V1\r\n\r");
00055             
00056             return SDCARD_V1;
00057         }
00058     }
00059     
00060     debug("Timeout waiting for v1.x card\r\n");
00061     return SDCARD_FAIL;
00062 }
00063  
00064  
00065 int initialise_card_v2() {
00066     for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
00067         wait_ms(50);
00068         cmd58();
00069         cmd(55, 0);
00070         if (cmd(41, 0x40000000) == 0) {
00071             printf("Yuppie,v2 successful\r\n");
00072             cmd58();
00073             debug_if(SD_DBG, "\r\n\rInit: SDCARD_V2\r\n\r");
00074             cdv = 1;
00075         
00076             return SDCARD_V2;
00077         }
00078     }
00079     
00080     debug("Timeout waiting for v2.x card\r\n");
00081     return SDCARD_FAIL;
00082 }
00083  
00084 int cmd(int cmd, int arg) {
00085     cs_SD = 0;
00086     
00087     // send a command
00088     spi_SD.write(0x40 | cmd);
00089     spi_SD.write(arg >> 24);
00090     spi_SD.write(arg >> 16);
00091     spi_SD.write(arg >> 8);
00092     spi_SD.write(arg >> 0);
00093     spi_SD.write(0x95);
00094     
00095     // wait for the repsonse (response[7] == 0)
00096 for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
00097         int response = spi_SD.write(0xFF);
00098         if (!(response & 0x80)) {
00099             cs_SD = 1;
00100             spi_SD.write(0xFF);
00101             return response;
00102         }
00103     }
00104     cs_SD = 1;
00105     spi_SD.write(0xFF);
00106     return -1; // timeout
00107 }
00108  
00109  
00110 int cmd58() {
00111     cs_SD = 0;
00112     int arg = 0;
00113     
00114     // send a command
00115     spi_SD.write(0x40 | 58);
00116     spi_SD.write(arg >> 24);
00117     spi_SD.write(arg >> 16);
00118     spi_SD.write(arg >> 8);
00119     spi_SD.write(arg >> 0);
00120     spi_SD.write(0x95);
00121     
00122     // wait for the repsonse (response[7] == 0)
00123     for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
00124         int response = spi_SD.write(0xFF);
00125         if (!(response & 0x80)) {
00126             int ocr = spi_SD.write(0xFF) << 24;
00127             ocr |= spi_SD.write(0xFF) << 16;
00128             ocr |= spi_SD.write(0xFF) << 8;
00129             ocr |= spi_SD.write(0xFF) << 0;
00130             cs_SD = 1;
00131             spi_SD.write(0xFF);
00132             return response;
00133         }
00134     }
00135     cs_SD = 1;
00136     spi_SD.write(0xFF);
00137     return -1; // timeout
00138 }
00139  
00140  
00141 int cmd8() {
00142     cs_SD = 0;
00143     
00144     // send a command
00145     spi_SD.write(0x40 | 8); // CMD8
00146     spi_SD.write(0x00);     // reserved
00147     spi_SD.write(0x00);     // reserved
00148     spi_SD.write(0x01);     // 3.3v
00149     spi_SD.write(0xAA);     // check pattern
00150     spi_SD.write(0x87);     // crc
00151     
00152     // wait for the repsonse (response[7] == 0)
00153     for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
00154         char response[5];
00155         response[0] = spi_SD.write(0xFF);
00156         if (!(response[0] & 0x80)) {
00157             for (int j = 1; j < 5; j++) {
00158                 response[i] = spi_SD.write(0xFF);
00159             }
00160             cs_SD = 1;
00161             spi_SD.write(0xFF);
00162             return response[0];
00163         }
00164     }
00165     cs_SD = 1;
00166     spi_SD.write(0xFF);
00167     return -1; // timeout
00168 }
00169  
00170 uint64_t sd_sectors() {
00171     uint32_t c_size, c_size_mult, read_bl_len;
00172     uint32_t block_len, mult, blocknr, capacity;
00173     uint32_t hc_c_size;
00174     uint64_t blocks;
00175     
00176     // CMD9, Response R2 (R1 byte + 16-byte block read)
00177     if (cmdx(9, 0) != 0) {
00178         debug("Didn't get a response from the disk\r\n");
00179         return 0;
00180     }
00181     
00182     uint8_t csd[16];
00183     if (read(csd, 16) != 0) {
00184         debug("Couldn't read csd response from disk\r\n");
00185         return 0;
00186     }
00187     
00188     // csd_structure : csd[127:126]
00189     // c_size        : csd[73:62]
00190     // c_size_mult   : csd[49:47]
00191     // read_bl_len   : csd[83:80] - the *maximum* read block length
00192     
00193     int csd_structure = ext_bits(csd, 127, 126);
00194     
00195     switch (csd_structure) {
00196         case 0:
00197             cdv = 512;
00198             c_size = ext_bits(csd, 73, 62);
00199             c_size_mult = ext_bits(csd, 49, 47);
00200             read_bl_len = ext_bits(csd, 83, 80);
00201             
00202             block_len = 1 << read_bl_len;
00203             mult = 1 << (c_size_mult + 2);
00204             blocknr = (c_size + 1) * mult;
00205             capacity = blocknr * block_len;
00206             blocks = capacity / 512;
00207             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);
00208             break;
00209         
00210         case 1:
00211             cdv = 1;
00212             hc_c_size = ext_bits(csd, 63, 48);
00213             blocks = (hc_c_size+1)*1024;
00214             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);
00215             break;
00216         
00217         default:
00218             debug("CSD struct unsupported\r\r\n");
00219             return 0;
00220     };
00221     return blocks;
00222 }
00223  
00224 int cmdx(int cmd, int arg) {
00225     cs_SD = 0;
00226     
00227     // send a command
00228     spi_SD.write(0x40 | cmd);
00229     spi_SD.write(arg >> 24);
00230     spi_SD.write(arg >> 16);
00231     spi_SD.write(arg >> 8);
00232     spi_SD.write(arg >> 0);
00233     spi_SD.write(0x95);
00234     
00235     // wait for the repsonse (response[7] == 0)
00236     for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
00237         int response = spi_SD.write(0xFF);
00238         if (!(response & 0x80)) {
00239             return response;
00240         }
00241     }
00242     cs_SD = 1;
00243     spi_SD.write(0xFF);
00244     return -1; // timeout
00245 }
00246  
00247  
00248 int read(uint8_t *buffer, uint32_t length) {
00249     cs_SD = 0;
00250     
00251     // read until start byte (0xFF)
00252     while (spi_SD.write(0xFF) != 0xFE);
00253     
00254     // read data
00255     for (int i = 0; i < length; i++) {
00256         buffer[i] = spi_SD.write(0xFF);
00257     }
00258     spi_SD.write(0xFF); // checksum
00259     spi_SD.write(0xFF);
00260     
00261     cs_SD = 1;
00262     spi_SD.write(0xFF);
00263     return 0;
00264 }
00265  
00266 static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
00267     uint32_t bits = 0;
00268     uint32_t size = 1 + msb - lsb;
00269     for (int i = 0; i < size; i++) {
00270         uint32_t position = lsb + i;
00271         uint32_t byte = 15 - (position >> 3);
00272         uint32_t bit = position & 0x7;
00273         uint32_t value = (data[byte] >> bit) & 1;
00274         bits |= value << i;
00275     }
00276     return bits;
00277 }
00278  
00279 int disk_initialize() {
00280     int i = initialise_card();
00281     debug_if(SD_DBG, "init card = %d\r\n", i);
00282     sectors = sd_sectors();
00283     
00284     // Set block length to 512 (CMD16)
00285     if (cmd(16, 512) != 0) {
00286         debug("Set 512-byte block timed out\r\n");
00287         return 1;
00288     }
00289     else
00290     {
00291         printf("Hey,block init succesful\r\n");
00292     }
00293     
00294     spi_SD.frequency(1000000); // Set to 1MHz for data transfer
00295     return 0;
00296 }
00297  
00298 int FUNC_WR_SD(const uint8_t *buffer, uint64_t block_number)
00299  
00300 {
00301     // set write address for single block (CMD24)
00302     if (cmd(24, block_number * cdv) != 0) {
00303         return 1;
00304     }
00305     
00306     // send the data block
00307     write(buffer, 512);
00308     printf("Written Successfully bro \r\n");
00309     return 0;
00310 }
00311  
00312 int write(const uint8_t*buffer, uint32_t length) {
00313     cs_SD = 0;
00314     
00315     // indicate start of block
00316     spi_SD.write(0xFE);
00317     
00318     // write the data
00319     for (int i = 0; i < length; i++) {
00320         spi_SD.write(buffer[i]);
00321     }
00322     
00323     // write the checksum
00324     spi_SD.write(0xFF);
00325     spi_SD.write(0xFF);
00326     
00327     // check the response token
00328     if ((spi_SD.write(0xFF) & 0x1F) != 0x05) {
00329         cs_SD = 1;
00330         spi_SD.write(0xFF);
00331         return 1;
00332     }
00333     
00334     // wait for write to finish
00335     while (spi_SD.write(0xFF) == 0);
00336     
00337     cs_SD = 1;
00338     spi_SD.write(0xFF);
00339     return 0;
00340 }
00341  
00342 int  FUNC_RD_SD(uint8_t *buffer, uint64_t block_number) {
00343     // set read address for single block (CMD17)
00344     if (cmd(17, block_number * cdv) != 0) {
00345         return 1;
00346     }
00347     
00348     // receive the data
00349     read(buffer, 512);
00350     return 0;
00351 }