How to save Arduino Uno....

Hi, I was a happy owner of new arduino till I misconnected wires on the breadboard(so many tiny holes close by) and gave 12V to the analog in pin( at least that is what I think has happened). Atmeg got hot and since then, well nothing is same as before.

I would like to find out which part of my arduino is dead and replace it.

If I plug it to USB, pc gives it COM port as before, on diod goes solid and led 13 goes solid on. Reset button has no influence on these leds. If I try to send Blink sketch into it I get

Binary sketch size: 1,084 bytes (of a 32,256 byte maximum)
C:\Users\kingbean\Desktop\arduino-1.0.5\hardware/tools/avr/bin/avrdude -CC:\Users\kingbean\Desktop\arduino-1.0.5\hardware/tools/avr/etc/avrdude.conf -v -v -v -v -patmega328p -carduino -P\\.\COM1 -b115200 -D -Uflash:w:C:\Users\kingbean\AppData\Local\Temp\build6195023820293351526.tmp\Blink.cpp.hex:i 

avrdude: Version 5.11, compiled on Sep  2 2011 at 19:38:36
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
         Copyright (c) 2007-2009 Joerg Wunsch

         System wide configuration file is "C:\Users\kingbean\Desktop\arduino-1.0.5\hardware/tools/avr/etc/avrdude.conf"

         Using Port                    : \\.\COM1
         Using Programmer              : arduino
         Overriding Baud Rate          : 115200
avrdude: Send: 0 [30]   [20] 
avrdude: Send: 0 [30]   [20] 
avrdude: Send: 0 [30]   [20] 
avrdude: Recv: 
avrdude: stk500_getsync(): not in sync: resp=0x00

avrdude done.  Thank you.

I get three RX diod flashes while sending this code.

I did the loopback test and it is negative only RX with TX flash once together when I send some text.

From what I read around here and googled I suppose my USB communication chip is dead or its firmware is dead, or the Atmeg is dead.

To change the ATMEG seems to be the easiest. But is it enough to just put there new chip with bootloader physically or do I have do something more? Thank you

To change the ATMEG seems to be the easiest. But is it enough to just put there new chip with bootloader physically or do I have do something more? Thank you

If your UNO is not the SMD version then you can simply replace the ATmega chip with a new one with the Arduino bootloader. They are fairly easy to find and should cost less than $10 easily.

What does it mean SMD version? Mine is R3. Looks like the chip is just sitting in its socket. Problem is, if the problem is in the atmegchip or somewhere else.

kingbean: What does it mean SMD version? Mine is R3. Looks like the chip is just sitting in its socket. Problem is, if the problem is in the atmegchip or somewhere else.

SMD would refer to the chip being surface mounted, aka, tiny little black square soldered directly to the board rather than being a long rectangle DIP in a socket, DIP being a rectangular chip with 2 rows of pins coming off of it which then sit in a socket.

There are R3s in both DIP and SMD versions, the official is SMD. But if your is a socketed one then yeah you can replace the chip fine.

There isnt anything on the board itself to break in that way, its pretty much guaranteed to be the chip dead. The USB connection isnt made to the chip itself, dependant on board there is a second AVR or an FTDI chip soldered onto the board near the USB socket which handles the USB data and acts as a USB > Serial adaptor, the arduino itself is then programmed with that serial. So even if you have fried the arduino by feeding it 12V, then the USB chip is still likely intact and will respond to the operating system.

I got this one . Ordered it from amazon as genuine Arduino, says made in Italy and such. So from what you say I understand I can change the chip. Great, Ill try to get hold of one and change it. Physical change should be enough? Some programing after first turn on is not necessary?

Thank you

when you order your new 328 chip make sure that it has the bootloader installed. It is called Optiboot. Then just replace the chip (making sure it is oriented properly).

kingbean: If I plug it to USB, pc gives it COM port as before, on diod goes solid and led 13 goes solid on. Reset button has no influence on these leds.

Your symptoms strongly suggest that the main chip (the one in the socket) is dead. Replacing it with a new one, for example:

http://www.adafruit.com/products/123

... should fix it.

A slight difference. Just choose Uno or Duemilanove as your board type depending on what bootloader you install.

Thanks, nevermind I found the one for uno. I hope it will work. Thanks again...

Hello, I've got a similar problem with Arduino UNO: the LED connected to pin 13 is always on, and reset doesn't work, neither by pressing the switch nor connecting reset pin to GND. Besides, my PC doesn't recongize Arduino anymore. I bought Arduino just today, it used to work... I didn't do nothing that could have demaged the board... I was just trying to run "blink" scratch with very little delays (1ms). I don't understand why it happened... Is there a way to have my board working again, maybe by uploading the boatloader again? Could I have only demaged the ATMEGA? Probably, If I replaced the ATMEGA328, it might work again...

Try the loopback test first (see top of this part of the forum). Possibly the USB interface chip is damaged.

Running the blink sketch should certainly not damage it ... unless ... did you connect a LED to the board? Or are you looking at the on-board LED?

[quote author=Nick Gammon link=topic=178743.msg1327029#msg1327029 date=1374617174] Try the loopback test first (see top of this part of the forum). Possibly the USB interface chip is damaged.

Running the blink sketch should certainly not damage it ... unless ... did you connect a LED to the board? Or are you looking at the on-board LED? [/quote]

Yes, I did it, I connected a LED with a resistor and it worked with no problem. However, if a try now to connect them, the on-board LED turns-off, and the extarnal LED doesn't work...

I will try the loopback test and I'll post my results.

Hello, I tried the loopback test but nothing has changed. On-board LED is still always on, reset still does not work and my pc doesn't recognize Arduino.

What could be the problem?

What do you mean "nothing has changed"?

  1. Send data by typing. Everything you type should be echoed back. To send data, some terminal applications, like Serial Monitor, require pressing the Enter key or clicking a Send button. If exactly what you send is echoed back then the board passes the test. This means that the host computer hardware driver, USB cable, and USB to serial converter are all working.

Did your data get echoed back or not?

[quote author=Nick Gammon link=topic=178743.msg1327487#msg1327487 date=1374659048] What do you mean "nothing has changed"?

  1. Send data by typing. Everything you type should be echoed back. To send data, some terminal applications, like Serial Monitor, require pressing the Enter key or clicking a Send button. If exactly what you send is echoed back then the board passes the test. This means that the host computer hardware driver, USB cable, and USB to serial converter are all working.

Did your data get echoed back or not? [/quote]

Actually, since arduino isn't recognized by my PC, I cannot send anything from serial monitor. Indeed, there is no Arduino's COM port when I connect the board. When Arduino worked, there was its COM port.

great, I changed the chip and it seems to work. I put blink in it and it works. Thanks guys..... I have a extra question though, is there some kind of code or way to test that everything is working properly? that all pins function and such? Dont mean the obvious to test everything one by one using multimeter. Thank you