Problems using MicroSD slot on sb700EX

[BillC]

Hi, I am having trouble getting the microSD slot to work on a SB700EX.

I have now resorted to importing an existing project that runs on a MOD5270 with a normal size SD card (not micro), this program is running on the SB700EX and all is OK exept the microSD.

The card is a Sandisk 8GB microSDHC card formatted to FAT32 and it can read/write under windows 7.

Does anyone know if there is any changes I need to make to my existing program to use the MicroSD slot on an SB700EX.

Thanks, Bill

[rnixon]

You have to check and make sure the flash card works in plain spi mode. I think some are sdio only, which need more signals than just spi. Not sure how you can confirm, hopefully it would be on the datasheet.

[rnixon]

A quick google search of sd vs sdhc provided:
Secure Digital Cards have been around for nearly 10 years, SDHC Cards are a newer version developed for use with digital cameras and other such devices that not only a require a higher capacity card, but also one that comes with a performance to match. SDHC cards are designed for devices that are compatible with the SD 2.00 specification. Products designed exclusively to support previous SD specifications 1.0 and 1.1 will not be able to utilise SDHC cards.

[BillC]

thanks for the info, the card didnt come with any hardware datasheet, it just labeled as a standard microSD card.

Does anyone know if the SB700EX hardware/software is compatable with the SD2.00 spec ? It seems that most of the cards available now are SDHC.

Thanks, Bill

[rnixon]

Bill, looking at the sandisk site it appears you can buy sd or sdhc. Why not get a sd card and try it? Although data sheets may not come in a store bought package, it doesn't mean they don't exist. Have you looked at the sandisk site? From your first post is seems you have an sd card that works, and a sdhc that does not. So it would seem you need sd.

[BillC]

Hi again, I also have a mod5270 dev board that has an SD slot (not microSD) and it is the code from that project that I am now using as the basis to test out the microSD slot on my new SB700EX.

I have today purchased a a 2gb microSD (not MicroSDHC) from BestBuy, this also does not work on the SB700EX, so the SB700EX is either faulty or there are some programming changes that I need to make for the SB700EX.

I am using the file "FileSystemUtils.cpp" that was in one of the EFFS example directorys on release 2.5.3 CD.

Has anyone used these routines on a SB700EX and should they work on this device ?

Thanks, Bill

[rnixon]

Hi Bill,

I would have expected that to work. A couple of things to check:
1. Just verifying that you are rebuilding for the sb700ex from source (sounds that way)
2. For each for the file system function calls, like mounting, card detect, etc, is the code checking the return values, and can you tell us what the return value is for each of the effs function calls? If the example does not not have them, you need to add them yourself. That might help narrow things down.

[rnixon]

Also, how about building and running a effs example with no changes at all, just as a test?

[BillC]

Hi again, in desperation I took the cover off the SB700EX and played around with the SD slot and blasted it with the spay from a can of compressed air, and believe it or not its now working with both microSD and microSDHC cards.

So all is well, I can confirm that the FileSystemUtils.cpp works on this device.

thanks for all your help.

Bill