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SD card boot delay?

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Peabody:
I'm working on a microSD card bootloader for MSP430 processors, and need to know if I need to add a delay to allow the SD to boot up and become responsive - in addition to the time the processor needs to boot up.  The data I've seen on SD cards specs "Power Up Time" as 250ms.  But it defines that as "0V to Vdd min".  So that appears to be talking about the slope of the Vdd voltage.  Besides, I can't imagine an SD card requiring 1/4 second to boot up.

Does anyone know what the best practice is for adding such a delay?  The cards will be small SD cards, not SDHC.

I assume the same issue would apply to hot insertion.  The CD(Dat3) pin will go high immediately, but is additional delay required?

Jeroen3:
SD cards have a quite a powerful processor inside. I'd guess the card simple doesn't respond when it's not ready yet.

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