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Topic: i've bricked my duemilanove (Read 614 times) previous topic - next topic


it has happend in the end. i've transformed my arduino in a nice useless brick.
i was playing around with motors, and it stopped working.
then decided not to load any new sketch
this is the error:

avrdude: stk500_getsync(): not in sync: resp=0x00
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

now a bit more.
the pin that i was using in pwm seems to be always output low.
when i start uploading the rx led is blinking faintly.
no 13 led lights, also when reset button pressed.
shall i order a new atmega chip or the whole board?
well i'm not sure that reburning the bootloader will be enought.
someone has ideas?


you probably just burned out the chip, its generally not a wise idea to run motors (or much of anything) directly from the arduino pins due to the fact that it does not have much current that can pass tru it

you can remove the chip and install a jumper wire in the chip socket tween pins 1 and 2,  when you send data out of your pc to the arduino that wire should loop the same data back to the ftdi chip and pc, If you want to check


i know that's not normally a good idea, that's why i was using a darlington transistor and using the vin pin and not the 5v one... but... i just don't know what happened....
but thanks for the idea of shortcutting to test usb to serial chip....


Yeah probobably a new chip jobby  :(

A couple of quid at the most.

Not too bad (could have been much worse)

Yeah try the loopback first though.



ohh... that's nice... well...
the board seems to work.
at least the trick worked, pretty amazing...
but i still want to know what happened...
i did only two thing that i'm not sure were correct:
-programmed it while on external power supply.
-no loopback diode in the driving motor cirquit. but i was using npn darlington (in the scheme it seemd to have inside a diode to keep the transistor safe).
what should i avoid next time?


got a schematic of what you wired

I think a lot of things, and I usually find out after the fact I was wrong


Feb 04, 2010, 11:22 pm Last Edit: Feb 04, 2010, 11:23 pm by Grumpy_Mike Reason: 1
-no loopback diode in the driving motor cirquit.

That's my guess. And they are called flyback diodes. Loopback is where you put the output of a communications poet back to its own input.

but i was using npn darlington (in the scheme it seemd to have inside a diode to keep the transistor safe).

There are diodes inside the darlington driver chips (not individual drivers) but did you wire them up to the supply?

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