display_update: Sending packet failed


New member
First of all, congrats on a wonderful program. Even though it seems it needs a bit of ironing out some glitches.

Ok, here's my problem: After some time (in this case about 2.5 hours, but it varies) of running cc2 the display turns itself off. The log for my LCD screen (lcd_631.log) shows this message:

Sun 26 18:49:45 WARNING   display_update: Sending packet failed.
(actually it gets repeated a lot, about two or three times per second of logs)

After getting this message, even when I stop the service, from the "tray" icon or even more forcefully by stopping cc2service and restarting, the display does not come on again, and the only way to resume it is unplugging the USB cable and replugging it. Also, when this has occurred, the 631_WinTest.exe seems to think that COM5 (the virtual COM port for CFA631-USB) is "in use".

I'm running WinXP pro SP2, on an Athlon XP 2000+ with 1.5 GB RAM. I'm also running BOINC which keeps my CPU quite busy, and I don't have a modem, so the only "COM" activity should be the 631 module.
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New member
Not sure about the virtual com port at 5. I loaded the drivers, checked the control panel and found the CFA 631 on com 3. Added the CC2 software and configured the CFA 631 for com 3 as per the contol panel. I believe this is how it should go, this setup works perfectly for me.

Now, unless I`m much mistaken (admin/tech will confirm/deny this), if I add another panel then it will go on the virtual com port. I will be adding a 634 soon so this is how I see it so far. I believe (again I could be wrong) this is how they both maintain different com ports and still physically work.

If (and I stress IF) this theory is correct so far and you only have one LCD panel (the CFA 631 USB) then this could explain the freezing up.



I have moved my displays a few times and for some reason, my 634 keeps the same COM port and my 631 takes the next "unused" port. If it originally on COM 3, it will go to COM 5. It seems as though CC2 or Windows does "give up" the original COM port the 631 is attached.

Go into Control Panel--> Ports (COM & LPT) and right click on your 631 and click on Properties. Goto to Port Setting--> advanced. Here you can change the COM Port Number. When I bring down the menu, it reports COMs 1 thru 5 in use (my 631 is currently on COM 6). The MB takes COMs 1 & 2, my 634 takes COM4. This means that my 631 was previously on COMs 3 & 5.

For some reason, Windows did not let go of COMs 3 & 5 when I unplugged my 631's USB cable. No problem, tho.

Use the pull menu to change your 631's port to any "in use" port that you KNOW is not in use. It will give you a warning then do what you request.

After you do this you will have to reconfigure CC2 to use this "new" port #.

Also, FWIW, I had problems with my 631 occasionally stopping with earlier BETA versions. About the time RC versions started coming out, a newer USB driver was also released. There is thread on this, where you can download the latest drivers.

Finally, do NOT pull the USB cable. You can go into Control Panel and uninstall the 631 there. I can't remember if is in the Port menu or the USB menu (I think the USB menu). Do it there and Windows will prompt you the "found new hardware" tray icon. Reinstall the 631 and everything should return.