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Topic: Auto reset doesn't work on Duemilanove (Read 720 times) previous topic - next topic

cepa

Hey, I just got an arduino from ebay http://www.ebay.com/itm/Arduino-ATmega328-Infrared-IR-LCD1602-DIY-Starter-Kit-6-/270793091739?pt=LH_DefaultDomain_0&hash=item3f0c86aa9b this one to be exact. And the auto-reset on this thing doesn't work. How can I fix this. Whenever i try to upload anything to it I have to wait till the RX led flashes then reset, otherwise i get an error that looks like this.
Code: [Select]
avrdude: stk500_getsync(): not in sync: resp=0x00

johnwasser

Might be a bad capacitor coupling the serial chip to the reset line.  Might be a short between Reset and +5 but that would cause the power to short out when you push the reset button.  I'm going with bad capacitor.

Doesn't look quite the same as a real Arduino.  Looks like the "Made in Italy" in the corner near the USB connector is missing and some of the silkscreen is a bit different.  Probably a clone.
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cepa

Yea It's probably a clone. Which capacitor should i check?

johnwasser

Check that the auto-reset pads (just behind the USB connector) are jumpered.  Follow the traces from those pads to find the capacitor.
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cepa

Yes, reset thing is bridged, but I can't follow the trace, it goes under a chip and then I lose it.

johnwasser

http://arduino.cc/en/uploads/Main/arduino-duemilanove-schematic.pdf

The capacitor in question is C13.  From the board layout that's the bottom device in the vertical row of surface mount devices that includes three LEDs.
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cepa

I checked the C13 cap with a multimeter, it seems ok.

zoomkat

Just as a check, do you have anything (beyond the USB cord) connected to the arduino when you have the reset issue? If you do, disconnect all the stuff and see if it resets. Also, do you have the proper arduino selected in the IDE?
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cepa

Yes, the proper arduino is selected and everything is disconnected.

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