A car or handheld GPS device as laptop GPS source?
Hi all,

Have anybody here tried using a standalone GPS device as a GPS source for a major mapping software like Microsoft Streets and Trips, DeLorme Street Atlas, etc?

(I'm fancying this as an upgrade idea for my GPS receiver... seems like a nice thing to have, just in case you didn't bring your laptop along but need at least a primitive GPS)

I've been to a couple of GPS forums, and it seems that there are not much devices on the market that can work standalone and provide a GPS data output to the PC. OK, there are some (e.g., Garmim GPSMAP 60*) but I'm eager to hear more suggestions

Ken in Regina
I have a Garmin eTrex Legend HCx. It supplies GPS data through the USB connection to the PC. If a nav program is able to receive data directly from the USB port it will work with it.

I'm pretty sure all of the new models of eTrex (Legend, Vista, Venture) will supply GPS data through the USB port. Also, as you mentioned, the GPSMAP models 60 and 76 will. I think many of Garmin's other new handheld models like the Colorado, Oregon and Dakota will do it (eg. "Spanner" mode).

Streets&Trips will not work directly with these devices because it only knows how to access the data from a COM port at 4800bps. Other nav programs vary in their ability to use data from a COM port or USB port.

This problem can be resolved for all nav programs by getting a utility program called GPSGate. It will detect a GPS signal on the USB port or any COM port at any data speed from 4800bps to 115,200bps. It will then convert the data to come out on virtual COM ports at whatever speed you want to set it to.

So, I can connect my eTrex Legend HCx to the USB port, run GPSGate which will discover the signal, set GPSGate to output the signal on a virtual COM port at 4800bps, tell Streets&Trips to look at that specific virtual COM port and it will happily start tracking with my eTrex.

Similar actions will allow me to use my eTrex with any nav program that can't discover the GPS signal on the USB port.

GPSGate is inexpensive and has a 14-day free trial so if you decide to go down this road you can test it before paying for it.

My eTrex Legend HCx seems to have better performance in gnarlier conditions than any of the three USB and two Bluetooth receivers I own. This is probably true of many modern handhelds, like Garmin's, that are designed for handheld use in all sorts of situations.

So your idea of having a receiver that you can also drop in your pocket and pack around with you is a very good one.

By the way, any of the Garmin handhelds I've mentioned above are far from primitive. All of them allow you to add maps. All of them will autoroute just as well as a laptop nav program if you have autorouting road maps loaded. All of them have many of the other features of car nav devices or laptop programs. And some of them even have full paperless geocaching capabilities.

Aside from a big screen and complex trip planning features, about the only other thing you lose with a good handheld is the voice guidance instructions. The little guys just beep when a turn is coming up. You really won't lose anything significant if the laptop is left behind and you have to depend on one of these to get you around. And you can't fit a laptop in your pocket or purse very well, eh?!!


Thanks a lot for the advice!
Yes, I'm aware about S&T (and seems like, all other major mapping apps) being able to acquire NMEA data through COM port only and USB carries only proprietary protos like Garmin PVT...
I've already bumped into GPSGate; currently, I'm trying to squeeze a list of officially supported (or at least, known to work) devices from the developers.

And yes again, GPSMAP and eTrex are anything but primitive Looks like, GPS manufacturers (at least, Garmin) consider live GPS data output as a luxury feature, like embedded MP3 player or whatnot. So basically, seems that you can't find a "laptop receiver that can work standalone too": it's "a portable receiver that can relay data to laptop too"...

Though, I keep searching. Now I wonder if basic GPSMAP 60 (not Cx or CSx) can fit the description (eTrex Legend already does but GPSMAP is supported by freeware Garmin Spanner whilst for eTrex, you need GPSGate)...

Anyway, thanks again!
Actually, the I-gotU GT-120 works perfectly with Streets and Trips or Street Atlas as a GPS receiver, and if NOT connected to the netbook or notebook via the USB connector, works as a GPS recorder, holding up to 65000 points. So it works well with its software, which converts the USB to a COM port, downloads a recorded track to your computer, and also serves as the charger for your GT-120, which has a rechargable battery in it. No display, so you cannot use the GT-120 to SEE where you are going, but it does document where you have been, and also will geocode your photos with where you have been if you keep the clocks set correctly. I've commented elsewhere about the precision of the GT-120 compared to a unit with a better antenna, but it is still close enough to your real path for you to know where you were, and when you were there.
Ken in Regina
kAndy, I've never tried Spanner with my eTrex Legend HCx so I can't say if it works. I got GPSGate for its flexibility in a variety of connection situations (I have half a dozen receivers and at least half a dozen nav programs!) and I've never found anything it won't do so it never occured to me to try Spanner. I should do that just so I'll know.

Ken in Regina
Okay, I tried Spanner with my eTrex Legend HCx and it won't use it. It finds the GPS just fine but it says it lacks some features so it can't be used. I'm not surprised. Spanner hasn't been updated in years.

It's possible Spanner will work with the GPSMAP models. Although the latest ones shipping have been significantly updated and are as good as you can buy for performance and features, that line has been around quite awhile so it's possible Spanner might be aware of them and might use them.

GPSGate finds my Legend HCx instantly, identifies it as a Garmin USB GPS and starts to use it. I can set the GPSGate outputs so any nav program can use the data coming in, no matter how finicky the nav program is. It also allows me to run multiple nav programs at the same time because it will output the same data stream from the GPS receiver simultaneously on multiple virtual COM ports. Hardly a major necessity but it's a fun deal sometimes.

For me, it was 13 bucks well spent.

Zillion thanx to everybody who've replied! It was _really_ helpful.
A little bit of update, mainly for people who (like myself) would google through forums in a search for an answer to this very problem.

So recently, I've done a bit of practical testing myself.

1. eTrex Venture HC. Works like charm as external GPS data provider. No additional setup needed, just run GPSGate on your PC and some NMEA-compliant mapping software (in my case, it was Microsoft Streets and Trips).
Pros: cheap'n'rugged, no black magic needed to get it running in GPS mode.
Cons: only 24M memory, non-expandable. Means (in my case) you can upload _either_ Boston _or_ rest of S New England road map... That sux big time.
Overall, not much use as a car GPS, even as a backup solution. Though, a nice thing if you're planning a hike and bringing a laptop (to get to the place) plus good old paper maps along

2. Nuvi family. In addition to GPSGate, requires a little black magic to set up as external source: <removed expired link>

(summary: plug the cable off, turn GPS unit on, hold battery icon for ~10 sec, plug cable in, press Exit, enjoy)
Nuvi 255W would not be able to show the map by itself, Nuvi 265T, would.
Pros: really good for driving.
Cons: entering GPS mode is a little bit tricky. Not quite suitable for hiking. Though - Nuvi 500 or 550 might be the answer.

Nevertheless: if anyone else had a first-hand positive experience with plugging a standalone unit (especially, non-Garmin one) to a PC, your additions are welcome!
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