Mega runs OK via USB com, can not upload program

Hi all,

I have a Mega (RCUBE) that was fine in all aspects until I tried to change the USB baud rate (19600 and back to 9600).
Since then, the installed program runs OK and sends data over the USB as COM, but when trying to upload program' it does not recognize the same working com port for upload. I get communication timeout messages.
I can see the receive LED to blink, trying to establish communication, but it fails.
Here is what I have tried for no avail:

  1. Another usb and com ports and many resets.
  2. unistalled and reinstalled the computer com port.
  3. Another computer (all WinXP).
  4. New bootloader - can not update for the same problem.
  5. It does upload the program when I select in the Tools another board (1280 instead of 2560), but then my program fails, as expected. (can't get it back now, as it does not load!).
    It seems like something inside the board has changed.
    (By the way, in Tools, I am supposed to select a programmer. Which one?)
    My computer is WinXP, IDE 1.0.5
    Thanks.

samtal:
change the USB baud rate (19600 and back to 9600).

Change the USB baud rate where? You probably meant 19200 not 19600.

samtal:
4. It does upload the program when I select in the Tools another board (1280 instead of 2560), but then my program fails, as expected. (can't get it back now, as it does not load!).

Well the one page I found on this "RCUBE" thing clearly says it is based on the 1280, not 2560.
http://www.r3cube.com/r3cubeshop/index.php?route=product/product&product_id=30

samtal:
(By the way, in Tools, I am supposed to select a programmer. Which one?)

None. That is for what programmer is used when burning a bootloader, nothing to do with loading user-code.

Thanks all for your replies.
I just moved from Maple to Arduino, using several years old board I had (after several Maple board died for unknown reason, not to blame Maple for that)
Porting the software was easy (although its AVR vs. ARM)

Here are my comments to your kind replies :

  1. Yes, I meant 19200 baud, but it does not matter. You may use any number as long as both sides are the same (as clearly stated in Arduino documentation).
  2. As I was not sure about the RCUBE, I started first by chance to run it as Mega 2560, and it reacted very well, so why bother, until something changed. I still have no idea what it was, but it happened immediately after trying to change the baud rate (which did not work anyhow).
  3. I am back now to load and run as Mega 1280, using also 2560 pin-out, USB baud rate at 115200, and it seems to run OK.
    Thanks again.
    samtal