Tim:
Thank you for taking the time to share your experience.
It's interesting you went with AN10406, I have been trying to get AN10916
to
work, since it targets Cortex M3 devices.
I am not sure I am using CMD2 or CMD41, I will have to check the code when I
get home. I know that I have been using the same SD card code with the
LPC2148 for over 3 years now, it works great but I can't get it going
with
the LPC1756 board I have. I'm even reusing the same SD cards I used with
the
LPC2148.
I'm more and more thinking it might be a hardware issue. I don't
have
another board to test with, and having code that works for sure on a Cortex
M3 would definitely help.
Jean
On Wed, Dec 15, 2010 at 7:54 AM, Tim Mitchell
wrote:
> ----Original Message----
> From: l...
> [mailto:l... ] On Behalf Of
> Jean-Sebastien Stoezel Sent: 15 December 2010 12:52 To:
> l... Subject: [lpc2000]
> Crossworks
> sample project for sdcard support
>
> > Hello,
> >
> > I've been battling with this for a while now, I cant seem
> > to get any communication going between an lpc1756 and an
> > sdcard.
> > I've used code from cmsis, demo code from NXP and my own
> > code (that works on an lpc2148). I've used different
> > sdcards, I just can't get it to work.
> >
> > Does anybody have ready to run project for crossworks,
> > that exercises an sdcard on ssp/spi0 with a cortex m3?
> > This would help me narrow down the issue, possibly to a
> > hardware failure.
>
> I have just got mine working on LPC1758 but unfortunately I cannot share
> the code.
>
> However it is almost entirely based on the code in the NXP app note
> AN10406, which is not a great bit of coding but OK to start with. I changed
> the card initialisation to send ACMD41 instead of CMD1, as high capacity
> cards (which they all seem to be now) don't work with CMD1, and also
to
> check for block-level addressing instead of byte-level addressing. Init
> described on Chan's page http://elm-chan.org/docs/mmc/mmc_e.html
>
> One thing I did find is that some cards are really really slow to
> initialise.
>
> --
> Tim Mitchell
>
>
>