File content as of revision 16:7428828a5da2:

#include "mbed.h"
#include "mbed_debug.h"
#include "SDCard.h"
#include "all_funcs.h"
#include "Flags.h"
#include "pin_config.h"

SPI spi_SD(PIN2, PIN1, PIN3); // mosi, miso, sclk
DigitalOut cs_SD(PIN20);

void FCTN_INIT_SD()
{
    uint8_t sd_init_fail_count = 0;
    uint8_t sd_disk_init_fail_count = 0;
    all_flags = all_flags|SDCARD_INIT_STATUS;
    int sd_response = initialise_card();
    while(sd_response == 1)
    {
        sd_init_fail_count++;
        sd_response = initialise_card();
        if(sd_init_fail_count>3)
        {
            all_flags = all_flags|SDCARD_INIT_FAIL;
            printf("\rSDCard init failed\r\n");
            break;
        }
    }
    sd_response = disk_initialize();
    while(sd_response == 1)
    {
        sd_disk_init_fail_count++;
        sd_response = disk_initialize();
        if(sd_disk_init_fail_count>3)
        {
            all_flags = all_flags|SDCARD_DISK_FAIL;
            printf("\rSDCard disk init failed\r\n");
            break;
        }
    }
    if(sd_disk_init_fail_count<=3 && sd_init_fail_count<=3 )
    {
        printf("\rSDCard successfully initialized\r\n");
    }
    all_flags = all_flags&(~SDCARD_INIT_STATUS);
}

int  FCTN_RD_SD(uint8_t *buffer, uint64_t block_number) 
{
    all_flags = all_flags|SD_RD_STATUS;
    // set read address for single block (CMD17)
    if (cmd(17, block_number * cdv) != 0) 
    {
        all_flags = all_flags|SD_RD_FAIL;
        printf("\rReading from SDCard failed\r\n");
        return 1;
    }
    // receive the data
    read(buffer, 512);
    all_flags = all_flags&(~SD_RD_STATUS);
    printf("Read Successfully from SDCard\r\n");
    return 0;
}

int FCTN_WR_SD(const uint8_t *buffer, uint64_t block_number)
{
    all_flags = all_flags|SD_WR_STATUS;
    // set write address for single block (CMD24)
    if (cmd(24, block_number * cdv) != 0) 
    {
        all_flags = all_flags|SD_WR_FAIL;
        printf("\rWriting to SDCard Failed\r\n");
        return 1;
    }
    
    // send the data block
    write(buffer, 512);
    all_flags = all_flags&(~SD_WR_STATUS);
    printf("Written Successfully to SDCard\r\n");
    return 0;
}

    
int initialise_card() {
    // Set to 100kHz for initialisation, and clock card with cs_SD = 1
    spi_SD.frequency(100000);
    cs_SD = 1;
    for (int i = 0; i < 16; i++) {
        spi_SD.write(0xFF);
    }
    
    // send CMD0, should return with all zeros except IDLE STATE set (bit 0)
    if (cmd(0, 0) != R1_IDLE_STATE) {
        debug("No disk, or could not put SD card in to SPI idle state\r\n");
        return 1;
    }
 
 // send CMD8 to determine whther it is ver 2.x
    int r = cmd8();
    if (r == R1_IDLE_STATE) 
    {
        printf("Entering version2\r\n");
        return initialise_card_v2();    
    }   
    else 
    {
        debug("Not in idle state after sending CMD8 (not an SD card?)\r\n");
        return 1;
    }
}
 
int initialise_card_v2() {
    for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
        wait_ms(50);
        cmd58();
        cmd(55, 0);
        if (cmd(41, 0x40000000) == 0) {
            printf("Yuppie,v2 successful\r\n");
            cmd58();
            debug_if(SD_DBG, "\r\n\rInit: SDCARD_V2\r\n\r");
            cdv = 1;
        
            return 0;
        }
    }
    
    debug("Timeout waiting for v2.x card\r\n");
    return 1;
}

int disk_initialize() {
    int i = initialise_card();
    debug_if(SD_DBG, "init card = %d\r\n", i);
    sectors = sd_sectors();
    
    // Set block length to 512 (CMD16)
    if (cmd(16, 512) != 0) {
        debug("Set 512-byte block timed out\r\n");
        return 1;
    }
    else
    {
        printf("Hey,block init succesful\r\n");
    }
    
    spi_SD.frequency(1000000); // Set to 1MHz for data transfer
    return 0;
}
 
int cmd(int cmd, int arg) {
    cs_SD = 0;
    
    // send a command
    spi_SD.write(0x40 | cmd);
    spi_SD.write(arg >> 24);
    spi_SD.write(arg >> 16);
    spi_SD.write(arg >> 8);
    spi_SD.write(arg >> 0);
    spi_SD.write(0x95);
    
    // wait for the repsonse (response[7] == 0)
for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
        int response = spi_SD.write(0xFF);
        if (!(response & 0x80)) {
            cs_SD = 1;
            spi_SD.write(0xFF);
            return response;
        }
    }
    cs_SD = 1;
    spi_SD.write(0xFF);
    return -1; // timeout
}
 
 
int cmd58() {
    cs_SD = 0;
    int arg = 0;
    
    // send a command
    spi_SD.write(0x40 | 58);
    spi_SD.write(arg >> 24);
    spi_SD.write(arg >> 16);
    spi_SD.write(arg >> 8);
    spi_SD.write(arg >> 0);
    spi_SD.write(0x95);
    
    // wait for the repsonse (response[7] == 0)
    for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
        int response = spi_SD.write(0xFF);
        if (!(response & 0x80)) {
            int ocr = spi_SD.write(0xFF) << 24;
            ocr |= spi_SD.write(0xFF) << 16;
            ocr |= spi_SD.write(0xFF) << 8;
            ocr |= spi_SD.write(0xFF) << 0;
            cs_SD = 1;
            spi_SD.write(0xFF);
            return response;
        }
    }
    cs_SD = 1;
    spi_SD.write(0xFF);
    return -1; // timeout
}
 
 
int cmd8() {
    cs_SD = 0;
    
    // send a command
    spi_SD.write(0x40 | 8); // CMD8
    spi_SD.write(0x00);     // reserved
    spi_SD.write(0x00);     // reserved
    spi_SD.write(0x01);     // 3.3v
    spi_SD.write(0xAA);     // check pattern
    spi_SD.write(0x87);     // crc
    
    // wait for the repsonse (response[7] == 0)
    for (int i = 0; i < SD_COMMAND_TIMEOUT * 1000; i++) {
        char response[5];
        response[0] = spi_SD.write(0xFF);
        if (!(response[0] & 0x80)) {
            for (int j = 1; j < 5; j++) {
                response[i] = spi_SD.write(0xFF);
            }
            cs_SD = 1;
            spi_SD.write(0xFF);
            return response[0];
        }
    }
    cs_SD = 1;
    spi_SD.write(0xFF);
    return -1; // timeout
}
 
uint64_t sd_sectors() {
    uint32_t c_size, c_size_mult, read_bl_len;
    uint32_t block_len, mult, blocknr, capacity;
    uint32_t hc_c_size;
    uint64_t blocks;
    
    // CMD9, Response R2 (R1 byte + 16-byte block read)
    if (cmdx(9, 0) != 0) {
        debug("Didn't get a response from the disk\r\n");
        return 0;
    }
    
    uint8_t csd[16];
    if (read(csd, 16) != 0) {
        debug("Couldn't read csd response from disk\r\n");
        return 0;
    }
    
    // csd_structure : csd[127:126]
    // c_size        : csd[73:62]
    // c_size_mult   : csd[49:47]
    // read_bl_len   : csd[83:80] - the *maximum* read block length
    
    int csd_structure = ext_bits(csd, 127, 126);
    
    switch (csd_structure) {
        case 0:
            cdv = 512;
            c_size = ext_bits(csd, 73, 62);
            c_size_mult = ext_bits(csd, 49, 47);
            read_bl_len = ext_bits(csd, 83, 80);
            
            block_len = 1 << read_bl_len;
            mult = 1 << (c_size_mult + 2);
            blocknr = (c_size + 1) * mult;
            capacity = blocknr * block_len;
            blocks = capacity / 512;
            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);
            break;
        
        case 1:
            cdv = 1;
            hc_c_size = ext_bits(csd, 63, 48);
            blocks = (hc_c_size+1)*1024;
            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);
            break;
        
        default:
            debug("CSD struct unsupported\r\r\n");
            return 0;
    };
    return blocks;
}
 
int cmdx(int cmd, int arg) {
    cs_SD = 0;
    
    // send a command
    spi_SD.write(0x40 | cmd);
    spi_SD.write(arg >> 24);
    spi_SD.write(arg >> 16);
    spi_SD.write(arg >> 8);
    spi_SD.write(arg >> 0);
    spi_SD.write(0x95);
    
    // wait for the repsonse (response[7] == 0)
    for (int i = 0; i < SD_COMMAND_TIMEOUT; i++) {
        int response = spi_SD.write(0xFF);
        if (!(response & 0x80)) {
            return response;
        }
    }
    cs_SD = 1;
    spi_SD.write(0xFF);
    return -1; // timeout
}
 
 
int read(uint8_t *buffer, uint32_t length) {
    cs_SD = 0;
    
    // read until start byte (0xFF)
    while (spi_SD.write(0xFF) != 0xFE);
    
    // read data
    for (int i = 0; i < length; i++) {
        buffer[i] = spi_SD.write(0xFF);
    }
    spi_SD.write(0xFF); // checksum
    spi_SD.write(0xFF);
    
    cs_SD = 1;
    spi_SD.write(0xFF);
    return 0;
}
 
static uint32_t ext_bits(unsigned char *data, int msb, int lsb) {
    uint32_t bits = 0;
    uint32_t size = 1 + msb - lsb;
    for (int i = 0; i < size; i++) {
        uint32_t position = lsb + i;
        uint32_t byte = 15 - (position >> 3);
        uint32_t bit = position & 0x7;
        uint32_t value = (data[byte] >> bit) & 1;
        bits |= value << i;
    }
    return bits;
}
 
int write(const uint8_t*buffer, uint32_t length) {
    cs_SD = 0;
    
    // indicate start of block
    spi_SD.write(0xFE);
    
    // write the data
    for (int i = 0; i < length; i++) {
        spi_SD.write(buffer[i]);
    }
    
    // write the checksum
    spi_SD.write(0xFF);
    spi_SD.write(0xFF);
    
    // check the response token
    if ((spi_SD.write(0xFF) & 0x1F) != 0x05) {
        cs_SD = 1;
        spi_SD.write(0xFF);
        return 1;
    }
    
    // wait for write to finish
    while (spi_SD.write(0xFF) == 0);
    
    cs_SD = 1;
    spi_SD.write(0xFF);
    return 0;
}