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STM32F103ZG SDIO and DMA

Question asked by van_winkoop.henk.001 on Feb 4, 2012
Latest reply on Mar 3, 2012 by mueller.moritz
Hi,

I managed to read an SD-Card on the MCBSTM32EXL board in SD-Mode (not SPI-Mode) by developing my own driver. But writing does not succeed. If I exchange the FIFO address by a variable then afterwards this variable contains the last buffer value to be send. Checking the SDIO->DCOUNT register shows 0x200 before and 0x000 after the write operation. So this seems okay but on my oscilloscoop I do not see any data on the D0 signal. If I disable the DMA and execute a manual write to the FIFO then data is transmitted.
With reading I discovered that SDIO->DCTRL DTDIR  must be defined prior to DBLOCKSIZE otherwise no data is read.
I use SDIO blocksize of 512 and DMA DMA2_Channel4->CNDT set to 128. I read the errata sheet as there are some issues with the SDIO but not the one I encountered.
Who can help me out,
Thanks
Henk

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