Thanks John and Dennis, At least now I have something to look at. I will look into the CF problem next.
The database itself gets generated on a PC and then transferred to the CF Card. During testing and development, this could have been 20-30 times a day, constantly erasing and recreating the existing DB. We have also sent large numbers of JPGs along with the database in the past (there are none now, but have been before). So these cards have been written over a lot, perhaps that is the problem. I think to test this, I will send the device back to the field with a brand new card and see if the problem persists. If the user can go several days of normal use without the problem, then I'll be convinced that it is the card. Out of curiosity I just checked the CF cards we've been using: on the development machine (which has NEVER shown the error) I have a SanDisk CF Card. On the Testing machine that is having the problem, there is a PNY Technologies CF Card. I wouldn't be surprised if the SanDisk card isn't simply better than the PNY card, so there is something else to consider. Once actual field use begins, the database will be replaced every week or so, along with a fair number of images (like 100-300 a week). The purpose of the application would have every record in the database being updated and some new ones created. And it would be that way week in and week out, essentially forever. We may eventually port it over to very small Tablet PCs, but right now it is all Windows Mobile 5. This is one of the reasons I went with SQLite, so that down the road I wouldn;t have to reinvent the database piece of the software for a different platform. Given all this, I will definitely look into the link Dennis sent. The company is not going to be happy replacing CF cards all the time, so if that can extend the wear then it will be welcome. Thanks a lot, Joel On 4/13/07, Dennis Cote <[EMAIL PROTECTED]> wrote:
Joel Cochran wrote: > > Or do you mean over the course of the lifetime of a CF card it can > only be > used so much? That might apply to this scenario, these cards have been > written over continuously for the last 6 months. > Joel, Yes, that is exactly the problem. You should look at using a flash file system such as http://sourceware.org/jffs2/ that uses "wear leveling" algorithms to spread the writes over all the flash devices blocks if you are writing often. HTH Dennis Cote ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
-- Joel Cochran
