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nabeards
Joined: 27 Jun 2014 Posts: 2
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| Re: THANK YOU! |
Posted: Fri Jun 27, 2014 6:40 pm |
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| neochrome32 wrote: | ok getting some strange resulsts mainly all zero's...
its a problem with my code, and not yet got stuck..
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I, too, am in a situation where I'm getting all 0s. What was it that finally made your code start working?
Thanks!
nabeards |
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asmallri
Joined: 12 Aug 2004 Posts: 1663 Location: Perth, Australia
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| Re: THANK YOU! |
Posted: Fri Jun 27, 2014 7:26 pm |
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| nabeards wrote: | | neochrome32 wrote: | ok getting some strange resulsts mainly all zero's...
its a problem with my code, and not yet got stuck..
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I, too, am in a situation where I'm getting all 0s. What was it that finally made your code start working?
Thanks!
nabeards |
A common mistake in hardware implementations is a missing pull-up resistor on DO of the card. This often prevents the card being put into SPI mode and, as a result, the PIC will see a floating SPI bus and not data output from the card.
Another common error is insufficient current to the card, especially during writes (high impedance power source and/or insufficient filtering and bypass capacitance on the cards power supply). This can result in a card's embedded processor resetting and, as a result, being in native mode instead of SPI mode. When the happens the PIC again sees a floating SPI bus and not the expected output from the card. _________________ Regards, Andrew
http://www.brushelectronics.com/software
Home of Ethernet, SD card and Encrypted Serial Bootloaders for PICs!! |
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nabeards
Joined: 27 Jun 2014 Posts: 2
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| Re: THANK YOU! |
Posted: Fri Jun 27, 2014 8:08 pm |
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| Quote: |
A common mistake in hardware implementations is a missing pull-up resistor on DO of the card. This often prevents the card being put into SPI mode and, as a result, the PIC will see a floating SPI bus and not data output from the card.
Another common error is insufficient current to the card, especially during writes (high impedance power source and/or insufficient filtering and bypass capacitance on the cards power supply). This can result in a card's embedded processor resetting and, as a result, being in native mode instead of SPI mode. When the happens the PIC again sees a floating SPI bus and not the expected output from the card. |
Thanks Andrew! I'm actually able to send and receive data just fine to the card, it's just the CID and CSD that seem to be just giving me 0s. I thought it might be something particular with the stack or with the command I'm sending; I am getting the data bit but then just 0s. I tried two different-branded cards, both SDHC.
nabeards |
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