"Can't open COMM port" errors

merrypig · 03-06-06, 01:39 PM

Hi all,

I have a dell axim X51V and the Haicom HI303III CF gps receiver.

On the whole they're working great except for one annoying issue. I've searched the forums and found various issues that sound similar but most seem to be the opposite to what I find. Others seem to lose their CF/BT gps devices after a reset. I'm having the reverse...

For _ONE_ time after power is turned on (from standby, soft reset or hard reset conditions) I can use any of the gps applications to find my device correctly.

However, as soon as a close the comm port connection and try to reopen it I get a can't open the comm port error message and I can no longer talk to my gps.

I have to either remove the GPS and reinsert, or go into standby/back on my axim in order to be able to re-open the port.

It seems that the comm port is not being released fully when I close it - and the application either thinks the port is not there, or is already in use.

I have tried with the Wm5 managing my gps (sharing hte ports) and with it 'disabled' - but it seems to make little difference.

Can anyone shed some light on why I can't use my comm ports twice without a 'reset'? This is the only niggle I have with this pda... :(

jgoggan · 03-07-06, 10:51 AM

Actually, your problem seems to be very common. Over at the Mapopolis forums, tons of Axim users are reporting this with various CF GPS units. It appears that ALL CF GPS units are doing this in the Axim. I get it with the Pharos 180 and newer 360 CF GPS.

Basically, once the port has been opened and then closed, it can't do it again. It does not matter if WM5 manages the GPS with a virtual port or not -- the same thing happens.

To get around it, as you've seen, you can quickly slide the CF GPS up and then back into place -- it will then work again (so that you can avoid the soft reset). This is what Mapopolis users are currently doing -- this is what I'm doing.

Mapopolis believes this to be a problem with the Axims. They aren't getting it with any other units -- only Axims with CF GPS.

Note that it appears to happen with other apps too -- so it isn't a Mapopolis problem.

Again, you are not alone -- lots (all) of the Axim users discussing it at Mapopolis's site are seeing this. :(

- John...

silvscorp · 03-07-06, 11:34 AM

read the thread I posted below for the fix:

http://www.aximsite.com/boards/showthread.php?t=116265

jgoggan · 03-07-06, 11:38 AM

Um, how is your post for a fix for a reminders problem related to the fact that we can't reopen a COM port once a CF GPS has been opened and closed? I just don't see the connection. I don't see anything at all in that thread that would have anything to do with fixing this COM port problem.

Note that Mapopolis has done some extensive debugging. The port actually does reopen -- they get a handle to it just fine -- they can even adjust settings for it -- but once they try to read data from it, MS gives a "resource unavailable" error (even though the handle stays valid). This appears to be a significant problem with the Axims and CF-based serial ports...

If I'm missing something in your thread that has anything to do with this problem, please direct me to it. Thanks.

- John...

merrypig · 03-07-06, 11:41 AM

That thread seems to be related to calendars/notifications- are you suggesting that this is related to my comm port problem?

merrypig · 03-07-06, 11:50 AM

Thanks for your info about the mapopolis debugging jgoggan; I thought I'd have a laugh and try dell hardware support and see what they say. So far they've had me remove the battery.. doh. Dead end here I think.

jgoggan · 03-09-06, 01:34 PM

Indeed -- I think that we won't see any real solution until we get a real update from Dell. For now, when using CF GPS, I think we'll need to slide it out and reinsert...

- John...

silvscorp · 03-09-06, 05:44 PM

sorry, i put the wrong link, here you go
http://www.aximsite.com/boards/showthread.php?t=116265

jgoggan · 03-09-06, 05:53 PM

Well, it sounded good -- but is still not working for me. After I make the change, as soon as I plug in my CF GPS, I get a Device.exe crash pointing to the new elserial.dll file...

I will look into this more though when I have time -- thanks for the (proper) link! :)

- John...

silvscorp · 03-10-06, 12:09 PM

well make sure you edit the registery so it will point to Elserial.dll instead of defualt serial.dll.

You'll need to do a soft reset before everything start to take changes.

(soft reset via other programs. DO NOT use the button in the back of the PDA, it'll turn all registery change back to default unless you have tweak2k2 installed and safed regsitery to file.)

merrypig · 03-10-06, 12:43 PM

THANK YOU!!!!

This worked a treat for me. The soft reset is not needed if you don't have your CF card plugged in when you make the change. I simply plugged mine in after editing the registry and it prompted me that it was loading elserial.dll which was unsigned. I accepted and that was it. It worked!

I have verified that the registry setting remains after a soft reset, standby, removal of the card. The gps is always present now :)

I also tested with the gps 'sharing' utility enabled (manage my gps etc); while iguidance doesn't work with the virtual ports, it didn't screw up the registry. I've disabled it again - but for me that's fine.

I can now switch between apps without worry.

I can't thank you enough for this fix. It's made my experience with the axim just spot on now.