Arduino Mega problem

I'm new here and having trouble with my arduino mega 2560. I'm ready to by a new one but I thought that I should check with the pro at this forum first before bying a new one.

Anyway, thing is I thing I think I have short-circuited my mega board. It happens when I started my new led lightning system. In the box, where the mega is placed, was a loose cable that somehow short-circuited the board (I think that). There was some "smoke" coming from/near the usb port and I shut the board down.
At the time, I was running the board with 9v.

After that I did try to connect it again but it did not work.

I then took the board to the computer and tried to clear the eeprom but it do not pass the "upload". It got stuck there.
When I check the computer I can find the port it is connect to (com3)
After that I have done loop-back test and it passed the test.
So, what else can I do before I buy a new one? Can I make another test to see if the chip is burnt or something? The thing is that no part get hot when I plugged it in the computer and the power led and the yellow/orange led under port 13 and ground is on. The RX led is also flashing.

Please, can someone help me with this. I'm totally new at this kind of stuff and my english writing skills is not so good I'm afraid but I do hope that you understand what I mean.


You fried the board. It could be the power circuit or the ATmega2560 itself.

I can think of one more test, but you need a programmer.
With a programmer and the ICSP header, you could try to connect to the ATmega2560.

ok. So I guess I have to buy a new board then...I suspected that.
I don't realy understand the part about programmer and ICSP header but it feels that it would easier to just buy a new one instead. I'm totally lost when it comes to arduino I'm afraid :~
Anyway, thanks for you reply.


Normally a sketch is upload with the (virtual) serial port via the use.

The ICSP header are 6 pins. They are used for example to program a bootloader. But also a sketch can be uploaded via those 6 pins. But is programmer is needed for that. The programmer can be a USBasp programmer from Ebay for a few euros/dollars or even another Arduion board.

If you become an advanced user of Arduino, as some point you might want to use that.