> From: James Newton
> Sent: 2007 Mar 30, Fri 09:43
>
> I'm quite a few hours into attempting to connect a microSD 
> (aka TransFLASH) card to an MSP430F1611 and I'll be damned if 
> I can get any response back from the card.
> 
> I've read the datasheets, I've read the many available web 
> pages on the subject, I've checked, re-checked, double 
> checked and had others check the connections, and I'm looking 
> at the signals I'm putting out on a logic analyzer and they 
> are dead on exactly what is called for. And there is NO 
> response from x4 cards.


I'm going to do what is good for the soul here and admit what the actual
problem turned out to be. The spec calls for 4 bytes of argument to be sent
between the command and the CRC. I was sending 3 bytes. 

I'm not sure how many times I checked the analyzer display against the spec,
but it must have been 50 or more times. Didn't see that (obvious) difference
every single time. Another guy looked at it and said "hey, doesn't that say
4 bytes? This looks like 3 to me..."

Whereupon I said "No fxxking WAY!", changed the code, ran it and completely
freaked out when the card responded.

I'm not charging the client for about 2 days of otherwise billable time.
Some times I think it's a good thing I have a day job. Sigh. If it wasn't
for the fact that in the past I've pulled many a project out of the toilet
and saved more than a few other peoples bacon from the fire, I would quit
doing this sort of work.

Another point is that I have got to get a new unit that can export images of
the signals so that I can post them for other people to look at.

---
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