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[on:]

Can someone recommend source for cheap small capacity (32 Mb or more) SD cards?  Need it for Arduino project...

[Reply #1 on:]

Can someone recommend source for cheap small capacity (32 Mb or more) SD cards?  Need it for Arduino project...

Sure, go to walmart.

[Reply #2 on:]

For cheap, E-bay is where to look, but variable quality and shipping time may not be worth the savings.

http://www.ebay.com/sch/i.html?LH_BIN=1&_sacat=0&_from=R40&_nkw=SD+card&_sop=15

Lefty

[Reply #3 on:]

but variable quality and shipping time may not be worth the savings.

Couldn't agree more - some of the real cheap cards are more than shocking...

[Reply #4 on:]

Well when I said cheap I meant under $1   I need crap-load of them. Cheapest one I see on e-bay are $3-5 but that's for 2 GB. I'd be happy even with 8 MB, but doesn't look like there's price = capacity correlation
I'll try Craigslist and free-cycle   I had a bunch of 32 and 64 MB cards that I threw out... and now I need it, oh well

[Reply #5 on:]

I also looked for these a while back and didn't find any. As time goes on, the size of commonly available cards keeps increasing, but the smaller ones they replace seem to just disappear. 2GB is just way more than needed for a lot of data logging applications. I'd think someone would have a truckload of "obsolete" small-capacity cards they'd be selling at bargain prices.

[Reply #6 on:]

The small cards keep going up in price. If you ever have any, DO NOT THROW THEM OUT!

I am always looking for cards <512MB.

[Reply #7 on:]

The small cards keep going up in price. If you ever have any, DO NOT THROW THEM OUT!

I am always looking for cards <512MB.

Why? If you want a particular size then just get the cheapest card you can find and create a smaller partition on it...

As a bonus, newer cards will usually be much faster than the older ones. It's all good.

[Reply #8 on:]

I too am always looking for 'cheap'...and small capacity micro SD cards..

I can never find anything cheap/or under 2GB now a days..  (shame)

I'd like to find some

128MB
256MB
512MB
1GB cards...

and not pay out of the nose.. or pay for shipping & handling fees on 'each' card..

[Reply #9 on:]

The protocol used on SDHC is different not backwards compatible.

[Reply #10 on:]

The protocol used on SDHC is different not backwards compatible.

I'm having nightmares that soon they'll only stop making non-SDHC cards 
Anyway after digging online, I found decent deal on eBay for lot of used 256Mb microSD cards ($.99 plus shipping), and $.99 adapters. Totally comes up around $2.25 per unit (card+adapter+shipping), not too bad I guess...

[Reply #11 on:]

The protocol used on SDHC is different not backwards compatible.

Ehh... in all our cases, we're using the SPI fallback protocol anyway.  That is a non-optional part of the SD spec.  The only thing that differs is the initialization sequence and how blocks are addressed.  It would be foolish to implement a design that didn't interrogate the card to ensure the right method was used, so I don't see backwards compatibility suffering any time soon.

If I'm wrong, I'd love to hear the opposing viewpoint.

[Reply #12 on:]

The protocol used on SDHC is different not backwards compatible.

Ehh... in all our cases, we're using the SPI fallback protocol anyway.  That is a non-optional part of the SD spec.  The only thing that differs is the initialization sequence and how blocks are addressed.  It would be foolish to implement a design that didn't interrogate the card to ensure the right method was used, so I don't see backwards compatibility suffering any time soon.

If I'm wrong, I'd love to hear the opposing viewpoint.

It looks like you are right, I had no idea it's backwards compatible. Indeed latest WaveHC library for example does support SDHC cards!

[Reply #13 on:]

Then why do SDHC cards behave erratically in very old devices?

[Reply #14 on:]

Maybe it doesn't comply with the recommended interrogation sequence?  There's a flowchart in the SD specs showing you how to properly differentiate.  It's backward compatible.  If you (as a designer) just initialize and go, instead of probing and verifying behavior, you may end up using the wrong command set.  Just a guess.