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Member Since: December 10, 2009

Country: United States

  • Apparently there are a batch of bad Uno SMD edition Arduino's out there. Here is what tech support has told me:

    Yep, bad boards. It looks like we got a bunch of bad boards in from
    Arduino. Basically there is a problem with the bootloader and in needs
    to be reinstalled.
    I am thinking SparkFun may want to put up a blog post or something with instructions on how to install a working version of the bootloader on these puppies. rrc1962 and I can not be the only one who got boards from this batch.

  • Okay, doing more investigating it seems that this is a known problem with some Arduino's that are not the original non-SMD version:
    I am wondering what version of the optiboot boot loader actually works and then see if I can somehow reprogram the bootloader on the SMD Uno's I have.

  • For what it is worth I see references on the arduino.cc forums to some people having problems with some versions of the optiboot boat loader causing "flash amnesia." That seems to be exactly what I am seeing with the two SMD variant UNO's I have.
    Being as these are UNO's I have no easy way to reflash the boot loader, at least not until I order some more parts. B-(

  • Hm. I just got some Arduino UNO's from sparkfun. Two as part of kits and just one by itself.
    Two of these (one in a kit, and the one by itself) are the SMD variant UNO.
    To be clear: The SparkFun starter's kit came with the non-SMD UNO. The inventor's kit came with an SMD version UNO, and I bought a third UNO that was also the SMD variant.
    Now, when I program the SMD variant one and the non-SMD variant one (via the Arduino app for OS X, on a mac obviously) the program runs fine.
    However, with the SMD ones, if I remove power and then power it up again, the program is gone, or not running. It just goes back to the boot loader blinking the LED on pin 13.
    However with the NON-SMD one, I program it, I remove power, I put power back.. and the program is running like it should be.
    Am I missing something totally obvious? Nothing anywhere seems to refer to this difference in behavior, yet both of the SMD ones are showing this and the non-SMD one is working as all the documentation seems to suggest?
    An Arduino that does not run its program after being reset or powered up is not very useful.

No public wish lists :(