micro SD question

manzana

I have a simple task; take samples at 200/second for 24 hours. Seems like a job custom made for the microSD adapter. It doesn't come close to the capacity of the SD memory card. Trouble is, I can only do 8193 long writes successfully. Anything more and it goes south. Any ideas? I am using the PropBOE MicroSD code. Many thanks. Prop really rocks.

Mike Green

It's impossible to tell without more information. "goes south" is not very informative. Some thoughts ... 8193 long writes is just over 32K and that's a common cluster size. The various SD card objects are perfectly happy transitioning from one cluster to another, but that takes more time since several blocks have to be allocated to start the new cluster. You might try formatting the card with a larger cluster size. You might also try pre-allocating the file using your PC, filling it with zeroes or spaces or some other value. You might post the exact code you're using. Often this sort of problem has nothing to do with OBEX or Parallax example code.

JonnyMac

Could be the quality of the card. I wrote an animation recorder program that would barf after about 20 seconds; on changing to a higher quality card the problem went away.

manzana

thanks guys. Will give it a shot. I just have it in a simple loop. I can write ok up to 8193 times and read it back. Any more and it never ends the write loop. Will try a different card too.