byte MMC_ReadSector(byte *buffer, uint32_t sector)
{
if (!(_mmcState & MMC_INITED))
return MMC_NOT_INITED;
if (!(_mmcState & MMC_HIGH_DENSITY))
sector <<= 9;
MMC_SS_LOW();
if (MMC_Command(17,sector) != 0 || MMC_Token() != 0xFE)
return MMC_Release(READ_FAILED);
SPI_Receive(buffer,512); // WARNING! Will strip 2 CRC bytes as well
return MMC_Release(0);
}
byte MMC_WriteSector(byte *buffer, uint32_t sector)
{
if (!(_mmcState & MMC_INITED))
return MMC_NOT_INITED;
if (!(_mmcState & MMC_HIGH_DENSITY))
sector <<= 9;
u8 r = WRITE_FAILED;
SPI_Enable();
MMC_SS_LOW();
if (MMC_Command2(24,sector) != 0)
{
u8 d = 16;
while (d--)
SPI_ReceiveByte(0xFF); // pad
SPI_ReceiveByte(0xFE); // Send token
SPI_Send(buffer,512);
SPI_ReceiveByte(0xFF); // CRC
SPI_ReceiveByte(0xFF); // CRC
u8 status;
while ((status = SPI_ReceiveByte(0xFF)) == 0xFF)
;
if (status == 0xE5)
r = 0;
else
r = status;
while (SPI_ReceiveByte(0xFF) == 0)
;
r = MMC_Release(r);
} else {
r = MMC_Release(WRITE_FAILED);
}
return r;
}
byte MMC_Init()
{
return MMC_Release(MMC_Init2());
}
