enable or disable ata smart

    memset(cdb, 0, 32);
    cdb[0] = 0x0;
    cdb[1] = 0x0;
    cdb[2] = 0x1;
    cdb[3] = 0x0;
    cdb[4] = 0x7;
    cdb[5] = 0x7;
    cdb[6] = 0x1;
    if (enabled)
        cdb[7] = ATA_SMART_ENABLE; // d8
    else
        cdb[7] = ATA_SMART_DISABLE; // d9

    cdb[8] = 0x2;
    cdb[9] = 0x0;
    cdb[10] = 0x3;
    cdb[11] = 0x0;
    cdb[12] = 0x4;
    cdb[13] = 0x4F;
    cdb[14] = 0x5;
    cdb[15] = 0xC2;
    cdb[16] = 0x6;
    cdb[17] = 0x0;
    cdb[18] = 0x7;
    cdb[19] = 0xB0;
    for(i = 1; i <= 7; i++)
        cdb[19 + i] = i;