STM CircleOS forum / SD Card

repzak · 2009-06-18 19:13:21

Hello,

Anyone else has problem with the read function?

else if (DeviceMode == SD_DMA_MODE)
{
SDIO_ITConfig(SDIO_IT_DCRCFAIL | SDIO_IT_DTIMEOUT | SDIO_IT_DATAEND | SDIO_IT_RXOVERR | SDIO_IT_STBITERR, ENABLE);
SDIO_DMACmd(ENABLE);
DMA_RxConfiguration(readbuff, BlockSize);
while (DMA_GetFlagStatus(DMA2_FLAG_TC4) == RESET)
{}

I have problems where i end in this while loop, seems like DMA wants more data but SD card will not transfer more data?

Any one have seen that too?

Kasper

repzak · 2009-06-21 15:55:34

Hello,

Found this in errata sheet,

Can anyone tell me what this means:?
Limited multibyte support with SDIO cards
Description
The SDIO standard allows multibyte transfers (to transfer from 1 up to 512 bytes of data),
which extends the block transfer of the SD standard.
In a multibyte transfer operation, CMD53 will not allow transfer, whatever the number of
bytes (in the allowed 1-to-512 range).
Workaround
If the SDIO card supports the multiblock mode, it is possible to transfer any number of 1-byte
blocks (in the 1-to-512 block range).

Kasper

# 1 2009-06-18 19:13:21 SD Card - Read...

SD Card - Read...

# 2 2009-06-21 15:55:34 SD Card - Read...

Re: SD Card - Read...

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