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From: Peter Dickerson on 7 Dec 2008 06:19
"Peter Jakacki" <peterjakacki(a)gmail.com> wrote in message
news:d8D_k.310$cu.56(a)news-server.bigpond.net.au...
>I have had problems with 2G cards which I suspect might not be SPI
>compatible, only SD compatible. However we could all be playing a never
>ending guessing game unless we have the same details you have such as the
>schematic and code and details of the exact card.
>
> Of course you should be trying other cards which I assume you have done,
> it's one of the very first rules of troubleshooting to eliminate various
> factors and home in on the cause. Try a 1G card or smaller.
>
> *Peter*
>
> Murray R. Van Luyn wrote:
>> Hi Tom,
>>
>> Well the electrical interface is now 100% correct, thanks to your advice.
>> I'm still getting no further than CMD8. There's still no reply from the
>> SD card no matter how many times it's polled. As far as I'm concerned the
>> signals being issued to the SD card are okay. I'm stumped!

All SD cards are supposed to work in SPI mode, even SDHC cards. What
problems I have had with entering SPI mode have been due to not sticking to
the letter of the spec - seventy odd init clocks, <=400kHz until ready and
all that.

A 2G SD card could be minus a bit and be SD, or plus a bit and be SDHC
(though I doubt anyone does such a thing).

(another) Peter.


From: Murray R. Van Luyn on 7 Dec 2008 21:10
Thanks Peter, Peter and Tom.

I seem to have solved my problem finally. The second bit of a six byte
command sequence transmission needs to be high. That makes CMD55 equal to
0x77 and not 0x37 (55) as I had it.

Thanks for all the advice on SD initialisation and debugging guy's.

Regards,
Murray R. Van Luyn.


"Peter Dickerson" <first.last(a)REMOVEtiscali.co.uk> wrote in message
news:493bb142_2(a)mk-nntp-2.news.uk.tiscali.com...
> "Peter Jakacki" <peterjakacki(a)gmail.com> wrote in message
> news:d8D_k.310$cu.56(a)news-server.bigpond.net.au...
>>I have had problems with 2G cards which I suspect might not be SPI
>>compatible, only SD compatible. However we could all be playing a never
>>ending guessing game unless we have the same details you have such as the
>>schematic and code and details of the exact card.
>>
>> Of course you should be trying other cards which I assume you have done,
>> it's one of the very first rules of troubleshooting to eliminate various
>> factors and home in on the cause. Try a 1G card or smaller.
>>
>> *Peter*
>>
>> Murray R. Van Luyn wrote:
>>> Hi Tom,
>>>
>>> Well the electrical interface is now 100% correct, thanks to your
>>> advice. I'm still getting no further than CMD8. There's still no reply
>>> from the SD card no matter how many times it's polled. As far as I'm
>>> concerned the signals being issued to the SD card are okay. I'm stumped!
>
> All SD cards are supposed to work in SPI mode, even SDHC cards. What
> problems I have had with entering SPI mode have been due to not sticking
> to the letter of the spec - seventy odd init clocks, <=400kHz until ready
> and all that.
>
> A 2G SD card could be minus a bit and be SD, or plus a bit and be SDHC
> (though I doubt anyone does such a thing).
>
> (another) Peter.
>


From: tporter on 9 Dec 2008 03:17
On Mon, 8 Dec 2008 11:10:18 +0900, "Murray R. Van Luyn"
<vanluynm(a)NOSPAM.iinet.net.au> wrote:

>Thanks Peter, Peter and Tom.
>
>I seem to have solved my problem finally. The second bit of a six byte
>command sequence transmission needs to be high. That makes CMD55 equal to
>0x77 and not 0x37 (55) as I had it.
>
>Thanks for all the advice on SD initialisation and debugging guy's.
>
>Regards,
>Murray R. Van Luyn.
>
<snip.
>
I'm not sure I understand your fix... CMD55 *is* 0x37 in the first 6
bits of the cmdindex -- that is, when you ae setting up the
cmdresponse, MCI_COMMAND & 0x003F should be 0x37 for CMD55.
No?

Be sure that your RCA used for CMD55 in *idle_state* (send a CMD7
first to check this) will be the card�s default RCA = 0x00000000
(Don't use some of the "fixes" out there - ie RCA=0x00010000) just use
0x0 (for SD cards). In other words, Set_Address should not normally
have been run at this point(unless you're up & running & are sending
an SDStatus inquiry(ACMD13) so RCA *should be 0x0 - if it's not,
certain very bad things will happen -- don't know what they are, but
they are likely to be bad.

I've only been wrong ~ 10^6 times this week, & it's still only Monday
night.

Best, Tom
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