running microSD card SPI clock at 30MHz

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#1
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hi,

I did some test on this overclocking (the clock should be just upto 25MHz) of SPI clock on microSD card, all of my microSD cards still work fine, so i want to know if anybody have got the problem at running 30MHz SPI clock on microSD cards?

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You have to read the data sheet for your specific microSD card.

I would guess that most will run at 30MHz quite happily.

However no regular AVR can run that fast. You can use the xmega at this speed. Or most ARM chips.

David.

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hi, all the microSD card datasheets i can found online said it's max 25MHz for SPI.

I use UC3B at 60MHz to get 30MHz SPI.

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Well if the data sheet says maximum 25MHz, do not be surprised if it fails sometimes.

For hobbyist use, you will probably be ok most of the time.

David.

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ok, thanks.