Problem uploading to Uno

Using Arduino IDE 1.x
1

Hi,

Hope someone can help with a frustrating problem.

I have Arduino Uno, which I am using for a high speed photography project. Operating system Vista.

I have successfully uploaded my sketch to the board many times. But sometimes I can only upload once before I get an error message "com port in use by other program". I do not have any other software running. To get round this, I have been quitting Arduino software, unplugging the USB lead, then start again. This is most frustating, as I constantly need to upload to change timer values.

Many thanks.

2

Have you ever connected a PDA or mobile phone to the computer?

3

I am in the same frustrating boat...yes I have connected a PDA to my computer before. However, I can't click on Tools in the IDEs window. Problem?

4

Typically, @Dermis' sort of problem is the PDA synchronization software. Regularly (e.g. every minute) the synchronization software probes all serial ports for the PDA.

@wood6626, the problem you've described seems to be typical of a computer that includes a Bluetooth port. If you have an external Bluetooth adapter, try removing it. If the adapter is internal, try disabling it. If neither apply, try closing the PDA software.

In any case, if you determine what caused the problem, please report back.

5

Thanks for the replies, Guys, much appreciated. I don't have a PDA or bluetooth. I have connected a mobile phone in the past.

The problem seems quite random, in that sometimes I can upload several times, before the dreaded "com port already in use" message occurs.

6

Dermis:
I have connected a mobile phone in the past

Did you install or use software that connected to the mobile phone from the computer?

7

Yes I have installed software to communicate with a mobile phone. I will uninstall it to see if it makes a difference. Thanks for the tip.

8

Update on the problem...

I did have Samsung PC3 studio mobile phone software, installed on my laptop, and it did have bluetooth, although I never used it. I uninstalled all software and drivers, before trying to upload. It failed again! =[
I did get it to work for about an hour, it seems the sketch should be saved before uploading to the Uno. After this time the cursed "com 4 in use" message appeared, and I'm back feeling frustrated. When it works, it's brilliant. When it doesn't, it drives me nuts!
Anybody got any other suggestions?
Thanks in advance.

9

Immediately after the first successful upload, run Task Manager. Change to the Processes tab. Open the window so all running processes are visible. Take a "picture" of the window (Alt+PrintScreen). Paste the picture into a convenient application like Paint or Word. Work until the error occurs. Create a new picture of the running processes. Compare the two pictures. Any new processes running?

After the error message is produced, run Task Manager. Is "avrdude" in the process list?

I've not used it myself but I've read that "Sysinternals Suite" (provided by Microsoft) can be used to determine which program has a serial port open.