Hi,
I'm sorry that my first post here sounds so bad, but either I'm doing something really silly or we've got a serious bug.
HW:
* brand new UNO
SW:
* Ubuntu Linux (tested several versions and arch 32, 64 & armel)
* Windows 7
SYMPTHOM:
* avrdude: stk500_recv(): programmer is not responding
* no way to upload anything from the IDE (nor from command line)
SOLUTION (temporary):
* you need black magic timing capabilities to press reset button on the board while starting upload command
QUESTION:
* is it really this the way it works ? (I mean you need to press the HW reset button while starting upload)
* is my board broken ?
I've spent half a day before I could upload the first sketch (now I have 80% success, pressing "reset" and "enter" simultaneously with avrdude from the cmdline).
I think I tried every possible combination of hw/sw versions, my conclusion (still in doubt) is that this seems a bootloader problem, the time it accepts the upload is too short: less than one second.
Any known solution to this issue ? It seems I'm not alone, googling for this problem yields hundreds of (unhappy) pages.
I thought I just could press a button from the IDE to upload a sketch, but this was not the case

--- Resolved adding a diode as suggested in
http://arduino.cc/forum/index.php/topic,73059.0.html