Cannot replace Blink program

Hi everyone,

I just got my first Arduino uno (SMD edition). Yay! Just now I am stuck in that I cannot get any other program to run apart from the example Blink one.

But in order:

I am running the Arduino IDE 1.0.5 on Debian Linux. The arduino is detected on /dev/ttyACM0.

After connecting the Ardiuno I called up the "Blink" example program and uploaded it to the board. Everything seemed to work perfectly. LED 13 is blinking.

It is just that now, no matter what other program I upload (like, e.g., the Blink program with different delay times or PIN 13 replaced by PIN 12) the original Blink program seems to persist. When I verify/compile and finally upload the new code I do not get any error messages. Instead the IDE says "Done uploading".

During the upload I see the Arduino doing its reset cycle: The PIN 13 LED is first flashing really fast three times. Then three times more slowly, once for a very brief moment, and then again twice at slow speed. Finally the TX is on for a short moment and LED 13 starts to resume the blink cycle. I am puzzled that I never notice the RX led go active during the upload. (Or is the upload of 1056 byes just too fast for me to see?)

Now that I think of it, I am not sure that even my original Blink upload went through. It is not 1 sec high and 1 sec low, instead the individual phases are about 0.5 sec. Is this perhaps the default program of a vanilla Arduino? Sorry, I didn't pay close enough attention before uploading the blink code.

As I final test I also tried a different USB cable. Obviously the results were identical.

I am sorry if this question should I already be asked/answered before.
Till now I could not find anything related.


I continued to poke around and got some new information (I think).

First, I upgraded to the 1.5.6 IDE from the Debian servers. This gave me the possibility to enable verbose output during compilation and upload.

Now I see that the compilation and everything seems to work fine without any obvious error messages.

However, the avrdude step gives me only


avrdude: Version 6.2, compiled on Nov 17 2015 at 16:12:18
Copyright (c) 2000-2005 Brian Dean,
Copyright (c) 2007-2014 Joerg Wunsch

System wide configuration file is "/usr/share/arduino/hardware/tools/avrdude.conf"
User configuration file is "/home/florian/.avrduderc"
User configuration file does not exist or is not a regular file, skipping

Using Port : /dev/ttyACM0
Using Programmer : arduino
Overriding Baud Rate : 115200

and hangs from there on for eternity. Accordingly the GUI is stuck at "Uploading...".

Now where do I go from here?!?

OK guys, sorry for spamming the forum. I found the reason.

Version 6.2-1 of avrdude in Debian seems broken.
Reverting to 6.1-4 solved my issues.


Did you figure out this solution and could maybe help me? Because I think i'm having the same problem. Have no uploaded sketch to the board, yet it keeps running the blink code which was the first one I uploaded.


Until you replace the blink sketch your old sketch will continue to run (unless you make an error in a sketch)

Did you change the delay times to something you would see visually eg from 1000 to 3000. ?

If you get the completed upload sketch then whatever you sent is usually the dominant sketch.