MCB2300: DMA FAILS ON SD/MMC INTERFACE
Information in this article applies to:
I have problems to implement an SD/MMC interface using the MCI protocol. I have used the driver files from the Real-Time Library for the LPC2368 or LPC2378 device. The code initializes the MMC/SD card and calculates the available memory, but any data read/write fails. It looks like a problem with the DMA.
Is there a known issue?
The DMA transfer only works to the USB RAM. Therefore it is required that you explicitly specify the memory region for the MMC buffers so that they are located to this specific memory space.
The following steps explain the configuration in µVision:
This configuration ensures that the DMA transfer buffers are located to USB RAM.
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Last Reviewed: Monday, September 24, 2007
of your data.