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Splitting Bluetooth GPS to Street Atlas and WxWorx/Threatnet

None of the usual solutions for splitting GPS were working for my new laptop with Earthmate Blue Logger, so I thought I'd post what finally worked. I'm not sure if my problems stemmed from using Bluetooth rather than USB to connect the GPS unit, or from my general lack of understanding of virtual ports and the causes of BSODs, or both. Still, in case anyone else is struggling with this, Franson GpsGate ended up working easily.

Before doing this, I'd suggest getting both Street Atlas and Threatnet working independently with the Bluetooth GPS (i.e. both might be accessing COM6), then change both ports after getting GpsGate to work. Also, make a full backup ready to recover from a recurring BSOD.

Here's the setup (Lenovo Thinkpad T61, 3GB Ram, built-in BT, XP Pro):
- Start GPS unit
- Go to Settings in Franson GpsGate
- Search for: Bluetooth GPS and NMEA compatible serial devices
- Select Output: Share GPS between several applications
- Add ports where you can access GPS data (I prefer higher numbers to avoid any future conflicts)
-- Virtual COM19 - for Delorme Street Atlas
-- Virtual COM20 - for Threatnet
- Software should now say: “Running OK. GPS data with valid position.”
- In Street Atlas options box, select COM19
- In Threatnet GPS options, select COM20
Close and re-open Street Atlas and Threatnet to take effect.

Here's what didn't work:
- An older version of Eltima Serial Splitter (which previously worked with my Thinkpad T41)
- DeLorme Serial Emulation Driver
- A new version of Eltima Serial Splitter

With the new Eltima software, I had several Blue Screens, apparently triggered by a conflict with Street Atlas. I did a full system recovery to get rid of them. It's a good lesson for anyone fooling with virtual ports: use Acronis True Image or another good backup program and be ready to boot from your recovery CD.

Here are the ports after everything is installed and working:
- COM4 (visible in Device Manager): Threatnet data
- COM5 (visible in Device Manager): Bluetooth - not used
- COM6 (visible in Device Manager): Bluetooth - used for GPS data without GpsGate
- COM19 (visible in GpsGate): For Street Atlas GPS
- COM20 (visible in GpsGate): For Threatnet GPS

I'm hoping with this new setup that tornadic supercells won't trigger a crash of GPS or Threatnet quite so often. It's funny how well everything seems to work on blue-sky busts.
 
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I'm hoping with this new setup that tornadic supercells won't trigger a crash of GPS or Threatnet quite so often. It's funny how well everything seems to work on blue-sky busts.

You know its funny you mention that, because I have the same problem, Only I use a simple GPS-Gate split between the spotter network client and GR3. I connect the GPS via USB. GR3 imports through COM2 and Spotternetwork imports through COM16.

I will drive for hours to the target zone and everything is fine but the second GR3 starts lighting up, things start disconnecting and stop functioning and I have to restart the laptop to get a new position/radar update...and itll only work for 5 minutes before I have to do it again...VERY FRUSTRATING and I give my partner props for not tossing it all out the window. Im wondering if it has to do with the amount of data coming in, Ive got unlimited data with my package so I dont know.

I thought it was just my laptop "forgetting" that im connected to the internet [the signal on my cell card from cingular never disconnects:confused:] So I was contemplating buying a newer laptop but now perhaps Ill try tinkering around with stuff 1st....interesting.
 
GPS Recommendations

Have you figured out what might be the cause of the loss in GPS signal? I do GPS software for a living so maybe I can help you troubleshoot your setup.

I'd like to learn more about the problem before I make suggestions, but I can think of a few general suggestions that should improve stability in the field:
  1. Consider a Bluetooth GPS device such as the Pharos i-GPS or TomTom Navigator 6 Bluetooth devices. Bluetooth devices can be thrown onto your dash for a better GPS signal and faster acquisition of a fix. The Pharos is my personal favorite because of its clear case; it's easy to tell if a connection is active, even from several feet away. I've left this device outside by accident a few times and it still works three years later. Bluetooth devices also do not require a driver, which simplifies things. BT devices are also more rugged. The BT "radio stack" (the software which manages wireless connections) can sense sudden signal loss caused when the battery dies or the GPS goes out of range. These features make BT GPS nice for the field. Of course, it is preferable to give the BT GPS a constant power supply to avoid drained batteries.
  2. If you use a mobile device, try and use a device with Windows Mobile version 5.0 or above. These devices have a built-in serial port splitter called the "GPS Intermediate Driver" (GPSID) which will split signals reliably for you without having to buy a splitter. Some mobile devices such as the E-Ten Glofiish have built-in GPS, making them easier to cart around.
  3. GPS is one technology where older communication technologies are better. Older, 9-pin RS232 serial GPS devices offer better stability than USB, SecureDigital, or CompactFlash devices. This is all because of simplicity; RS232 devices don't need any drivers, and therefore there is less that can go wrong ;) Since 9-pin ports are less common, the next best thing is Bluetooth.
  4. Avoid some specific GPS devices: the GlobalSat BT-338 (which turns itself off, very annoying), the Hewlett-Packard hw6515 (which crashes), and be careful with Garmin USB devices. Even though Garmin is the #1 manufacturer, Garmin has been dropping support for the well-established "NMEA" data protocol if favor of their own ever-chaing protocol. Be sure the device specs mention "NMEA" or "NMEA-0183" to be sure it'll work with your software.
Hope this helps! Microsoft will probably add serial-splitting to Windows Vista within a couple of years, too, which will help reduce the cost.
 
Even though Garmin is the #1 manufacturer, Garmin has been dropping support for the well-established "NMEA" data protocol if favor of their own ever-chaing protocol. Be sure the device specs mention "NMEA" or "NMEA-0183" to be sure it'll work with your software.

Street Atlas 2006 gives you a choice of devices, including "Delorme Earthmate" running at 9600 baud or "Generic NMEA" running at 4800 baud. It seems to default to NMEA at 4800 and now I'm wondering if choosing "Earthmate" at 9600 creates instability. Or maybe it takes the latest Earthmate Bluetooth device and SA 2008 to achieve some stability in the field. On the other hand, maybe GpsGate mediates the data better than Eltima Serial Splitter. All very confusing.

What makes it especially tough to resolve is that everything works fine until you really need it and you're in no position to spend an hour or two on the phone with tech support.
 
...maybe it takes the latest Earthmate Bluetooth device and SA 2008 to achieve some stability in the field...

The Earthmate/9600 baud combination transmits a protocol known as "Rockwell Zodiac," which DeLorme likes to use instead of the standard, NMEA. Earthmates have been known to freeze randomly on my test machines during development of GPS.NET, especially when their Virtual Port software is used, so avoid DeLorme devices now. (Earthmates don't seem to like rapid-fire connect-disconnect attempts.)

Do you tend to leave the GPS running constantly, or connect it only when you need it? It's preferable to leave GPS connections running as constantly as possible, mainly because it lets the device maintain a higher-precision fix.

What makes it especially tough to resolve is that everything works fine until you really need it and you're in no position to spend an hour or two on the phone with tech support.

Last I checked MS Streets & Trips shipped with a Pharos, so that would be my humble recommendation. It would help to ask the clerk if you can return the entire box if you're not happy with it; they may have an "open box" software restriction.
 
Do you tend to leave the GPS running constantly, or connect it only when you need it? It's preferable to leave GPS connections running as constantly as possible, mainly because it lets the device maintain a higher-precision fix.

It only goes off during long waits to avoid draining everything. Maybe I just need an Optima yellow top so I can stay running for a few hours.

Thanks for the tips!
 
I use Street Atlas 2006, and the yellow Earthmate receiver it comes with. To split the GPS, I use the free Delorme Serial Emulator . Here's what I do, to make sure there are no problems.

Install the Delorme Serial Emulator.
Make sure the Emulator is not on Auto-Start (it will always screw up, if it's on this for some reason)
Set the Emulator to "Off"
Start Street Atlas. (I have 4 USB ports, and using my rear left one for the GPS)
Get a 2-D or 3-D lock in Street Atlas.
Right click the Satellite icon on your system tray and turn to on. (Or just start the emulator however you wish). It should say "The emulator is now attempting to acquire a 3-D fix"

A green dot should appear letting you know it's working.
Right click the satellite dish icon again, and choose "Ports" this time.
Select all of them as NMEA.

This is the tricky part, as I have had to mess with it to find the right ones, but I use COM's "2, 5, 6" in that order. (Having the GPS connected to the rear, left USB port)

I then open GR3, and hit "Start GPS" and a list of COM ports open, I have this one set to "COM5."

Open SpotterNetwork, File>Settings> and Select COM6.

Walla, works every time as long as I remember to put the GPS unit into the same spot as the time before.
 
Dick McGowan said: "Walla, works every time as long as I remember to put the GPS unit into the same spot as the time before."

I think that's what causes most of the problems, switching USB ports after getting everything setup and working.
 
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Dick McGowan said: "Walla, works every time as long as I remember to put the GPS unit into the same spot as the time before."

I think that's what causes most of the problems, switching USB ports after getting everything setup and working.


Yup. I went so far as to label the two critical ones (GPS and phone cable) on the cords...and now that I use a USB hub, it is labeled.
 
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