SD card interfacing with LPC2364

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SD card interfacing with LPC2364

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by pratik_pimparkar on Wed May 27 23:24:58 MST 2015
Hi,
I am trying to interface an SDHC Sandisk 4GB card with my LPC 2364 processor.

I have detected the card and it goes into IDLE_STATE but I cannot get it out of it. The card does not take any instruction after CMD0. According to page 11 flowchart of "SDIO simplified specifications" from sdcard.org, I am writing CMD8 after CMD0. But this gives me a response of 0x05. i.e. it is in IDLE_STATE and the next instruction gives an ILLEGAL_COMMAND. I am sure the SD card is working properly in other devices. But according to this flowchart my SD card is unusable.

Could you please help me with this?

I have read all different forums and have read elm-chan's blog post but there does not seem to be good documentation for SDHC cards.

Please help me with this initialization.

Note: I am using SPI mode at 400khz and my hardware does not have any issues, I am getting all the signals on a Digital Oscilloscope.

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lpcware
NXP Employee
NXP Employee
Content originally posted in LPCWare by pratik_pimparkar on Sun May 31 02:33:25 MST 2015
According to the steps that I was following, it was correct sequence. My version of the card is 2.0 as it gives 0x05 as a response. For earlier versions the response is 0x01.
So, that part of the sequence is figured out.

The next problem I am facing is ACMD41 should respond with a 0x00 but I am still getting a response of 0x01. This shows that the card is still in the IDLE state and it does not come out of it to get further instructions. So I cannot read and write to my card as of now. Will keep the progress posted.

Inputs would be very helpful.. 

Please help !!

Thank you..
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