Embedded: SDHC SPI write issue - embedded

Question

I am currently working at a logger that uses a MSP430F2618 MCU and SanDisk 4GB SDHC Card.
Card initialization works as expected, I also can read MBR and FAT table.
The problem is that I can't write any data on it. I have checked if it is write protected by notch, but it's not. Windows 7 OS has no problem reading/writing to it.
Though, I have used a tool called "HxD" and I've tried to alter some sectors (under Windows). When I try to save the content to SD card, the tool pop up a windows telling me "Access denied!".
Then I came back to my code for writing to SD card:
uint8_t SdWriteBlock(uchar_t *blockData, const uint32_t address)
{
uint8_t result = OP_ERROR;
uint16_t count;
uchar_t dataResp;
uint8_t idx;
for (idx = RWTIMEOUT; idx > 0; idx--)
{
CS_LOW();
SdCommand(CMD24, address, 0xFF);
dataResp = SdResponse();
if (dataResp == 0x00)
{
break;
}
else
{
CS_HIGH();
SdWrite(0xFF);
}
}
if (0x00 == dataResp)
{
//send command success, now send data starting with DATA TOKEN = 0xFE
SdWrite(0xFE);
//send 512 bytes of data
for (count = 0; count < 512; count++)
{
SdWrite(*blockData++);
}
//now send tow CRC bytes ,through it is not used in the spi mode
//but it is still needed in transfer format
SdWrite(0xFF);
SdWrite(0xFF);
//now read in the DATA RESPONSE TOKEN
do
{
SdWrite(0xFF);
dataResp = SdRead();
}
while (dataResp == 0x00);
//following the DATA RESPONSE TOKEN are a number of BUSY bytes
//a zero byte indicates the SD/MMC is busy programing,
//a non_zero byte indicates SD/MMC is not busy
dataResp = dataResp & 0x0F;
if (0x05 == dataResp)
{
idx = RWTIMEOUT;
do
{
SdWrite(0xFF);
dataResp = SdRead();
if (0x0 == dataResp)
{
result = OP_OK;
break;
}
idx--;
}
while (idx != 0);
CS_HIGH();
SdWrite(0xFF);
}
else
{
CS_HIGH();
SdWrite(0xFF);
}
}
return result;
}
The problem seems to be when I am waiting for card status:
do
{
SdWrite(0xFF);
dataResp = SdRead();
}
while (dataResp == 0x00);
Here I am waiting for a response of type "X5"(hex value) where X is undefined.
But most of the cases the response is 0x00 (hex value) and I don't get out of the loop. Few cases are when the response is 0xFF (hex value).
I can't figure out what is the problem.
Can anyone help me? Thanks!

Answer 1

4GB SDHC
We need to see much more of your code. Many µC SPI codebases only support SD cards <= 2 GB, so using a smaller card might work.
You might check it yourself: SDHC needs a CMD 8 and an ACMD 41 after the CMD 0 (GO_IDLE_STATE) command, otherwise you cannot read or write data to it.

Answer 2

Thank you for your answers, but I solved my problem. It was a problem of timing. I had to put a delay at specific points.