sd card not working properly

[sonuprajapat]

hi i am working on sd card using spi in lpc2468 it is working fine . but when i do the power off  the card then card init correct but not read write . i can not understand the problem please help me . my code is...

Original Attachment has been moved to: SPI.C.zip

Original Attachment has been moved to: Spi_mmc.h.zip

Original Attachment has been moved to: MMC.C.zip

[sonuprajapat]

hi some help me on above question i am not understanding this problem please....

[sonuprajapat]

please give me replay....

[CarlosCasillas]

Hi Sonu,

If the code is working without the power cycle, it seems that it is a timing or power issue. You could try checking your power supply in order to discard some peaks that cause abnormal SD card operation, or trying adding a delay before the SD card initialization, in order to ensure that the card is already self-initialized for a correct communication.

Hope this will be useful for you.
Best regards!
/Carlos
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[sonuprajapat]

Hi Carlos

Thank you for your replay .

As you say  it may be . problem is that normally card is working fine but when i do the power off and then on of the system respectively then card initialization is fine but read write operation is not working . But when i do reset of whole system then it is working fine again.

thank you .