I think the problem is related (or maybe with the same reason) to that reported at Web server - eglibc. Basically, the eglibc based yocto image is not stable on executing stored sketches. You can try:
a) Download another yoct image, the so called uclibc at https://communities.intel.com/external-link.jspa?url=https%3A%2F%2Fdownloadmirror.intel.com%2F24355%2Feng%2Fsdcard.1.0.8… (link provided in another thread: Broken Link - v2 )
b) As in the steps you have followed for the non-working image: "Right-click the .bz2 file and select Extract here to start the extraction process."
c) As in the steps you have followed for the non-working image: "Format your card" (remember: FAT format)
d) Copy the extracted files in step b) to the SD (do not use df, use cp)
e) Boot with the SD
f) Upload the sketch
Please tell us if this works (it works for me, multiple times/apps, no failures so far)
It works well, the USB is now detected, and the sketch is persistent.
I get this behavior though:
After rebooting or power off then on, the persistent sketch doesn't run when USB is connected. when the USB is disconnected, the sketch runs.
Is this normal?
I've not experimented specifically this... but if this is the case, then I think it's an error or, at least, an unexpected behavior. I'll try to experiment a little bit further and let you know if I find something interesting.
It's good to know now at least the sketch is persistent and everything works when the USB cable is not plugged in, though.
BTW: Does your sketch have any specific behavior or it is a simple example just as the blink sketch?