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Can't read Card Specific Data from SD Card (rtems-4.9.0)
- Date: Thu, 09 Oct 2008 08:45:52 -0400
- From: rsg at alum.mit.edu (Robert S. Grimes)
- Subject: Can't read Card Specific Data from SD Card (rtems-4.9.0)
Thomas Doerfler wrote:
> Can you monitor the SPI signals at the SDCard with an oscilloscope, I
> think the proper relationship between SEL, CLK and Data lines is crucial.
>
Yes, of course they are - that's why I love my four channel 'scope!
> - - Did you verify the baudrate is correct (not too high)?
>
Yes. I had started with 6.25 MHz, but switched now to 391 kHz because
of the MMC startup requirement - same results. (While I'm at it, I will
only be using SD cards, so can I run only at the higher 6.25 MHz clock?