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Creating routes for a Garmin eTrex H

— How to create GPS routes and how to transfer them to the Garmin eTrex H.”

In addition to my earlier article on Getting started with a Garmin eTrex H GPS for walking, here’s a brief explanation of how I create routes and transfer them to the eTrex H.

Before we get started, there are a few points to mention:

• We’ll be using proprietary software and map products on Windows XP or above
• When creating a very basic route, we have no real need for waypoints, just via points – so I won’t be discussing waypoints here
• Sometimes the workflow might seem a bit convoluted, but as a routine I’ve gotten used to it and it will probably apply to almost any basic Garmin handheld device, not just the eTrex H!

Using Mapsource

As I explained in my Getting started… article, I use Garmin’s Mapsource software to plan and create routes, which doesn’t ship with the eTrex.

Mapsource (v6.15.11 illustrated here but v6.16.x works the same) is surprisingly clunky for a desktop software client. As the main interface between the eTrex H device and the computer, however, it’s pretty much essential and I can live with its limitations.

So with that in mind, let’s start up Mapsource now.

Drawing a route

First we’ll need to select our map product. Assuming it’s properly installed and unlocked, select it.

Select the map product you want to use

We need to find the starting location for our route. I often use Google Earth or Google Maps to do this: a satellite view offers a more human picture of car parking facilities and other features.

Use the Find menu and the Hand tool in Mapsource to drag to the location. The “+” and “-” keys will zoom in and out respectively.

Now select the Route tool and click on the map at the desired starting point.

Click on the map at the desired starting point

Point by point, draw a route out on the map. If you’re walking, you’ll obviously want to stick to paths and trails rather than proper roads. Mapsource isn’t too intuitive when you make mistakes, so try to minimise them wherever possible, making use of Edit > Undo / Ctrl Z. If you do need to go back and edit your points, then you should learn how to do that with the Route tool. Since I need to keep this article simple, I won’t cover it here.

Tip!

When drawing out a route, I again tend to use Google Maps or Google Earth with the pictures layer(s) turned on. This helps me ensure I don’t miss any beauty spots or places of interest (because people tend to take photos of them).

Showing the picture layer in Google Maps

Tip!

Always think of the real world when planning a route:

• Shorter is not necessarily easier or safer
• Map data (especially Garmin’s own topo maps) can be infuriatingly inaccurate, so check for updates and also your paper map
• Little details on the PC can help a lot on the trail – for example, if I’m going straight over a crossroads, I eliminate doubt by placing my next via point after the crossroads

Placing a via point after the crossroads

Caution!

It’s important to remember when drawing that the eTrex H only accepts a maximum of 125 points per route. This limit increases as we go up the food chain of Garmin GPS models. So what can we do with a long and/or complicated walk? The options are limited but I don’t mind. More on that below in the Preflight section.

Once you’ve finished drawing out the route, you might want to save it. The default file format is GDB, a Garmin proprietary format specific to Mapsource and as such not necessarily transferable to other software. Personally, I stick to GPX, which is an XML standard (albeit proprietary itself) and supported by all software and devices I’ve so far encountered.

Preflight

Years ago, I used to do graphic design. After the creative work was finished and in order to send the artwork off to the printer, a final – and sometimes highly technical – workflow would usually be necessary: Preflight.

In the same way, if because of length or complexity the route contains more than 125 via points, we will need to do another workflow before we can transfer our route to the eTrex H. If the route contains 125 or less via points, you can continue to Transferring GPS routes to the eTrex H.

With longer routes, we need to consider one of the following options:

1. Cutting out superfluous via points to get the total down to 125 points – this is easier than it sounds, because a clearly-defined trail rarely needs every kink to be marked with a point
2. Dividing a big route into multiple smaller routes – this in turn triggers another eTrex H-specific constraint, the grand total of points across all routes cannot exceed 500!

If you can’t work around the point limitations of the eTrex H by option 1, then option 2 will work for all but the most complicated routes. You just need to be comfortable with the idea of switching routes on the fly during your walk.

So speaking personally, the only practical inconvenience for me is having to keep an eye on the device when I know we’re nearing the end of one route, because then I’ll need to switch to the next one on the list.

Tip!

Cutting out the flabby via points or splitting a big route into a series of smaller routes could be a big headache. Mapsource certainly won’t help us.

Enter the resourceful Dutchman Edward Sackman and his brilliant WinGDB utility. Alongside Mapsource, I use WinGDB almost as much.

WinGDB is a multitool of functions that the folks at Garmin neglected to include in Mapsource, including facilities for route simplification (based on some excellent mathematics) and splitting. You can output the results to a file or to another instance of Mapsource.

Edward Sackman’s WinGDB (v3.44 shown)

If you’re planning more complex routes and you’re willing to accept the eTrex H’s limitations, then spend some time getting to know WinGDB.

Transferring GPS routes to the eTrex H

Without Mapsource or an alternative [1], you cannot transfer routes or tracks to or from the eTrex H because the serial interface cannot be read like a disk in the way that we might do with, say, a digital camera. So you’d otherwise be reduced to entering the points on the device manually, which is no fun at all.

So far we’ve prepared our route using Mapsource, so let’s go back to it now.

If you’ve installed the correct drivers for your eTrex H (see the Getting started… article for more information), transferring routes to it is simple using the Transfer > Send to device... menu:

Be sure not to pull out the cable or stop the operation before it’s finished. Also check the device to confirm that the transfer has completed. If your route contains too many points, the device (not the computer) will truncate it and display a message to that effect.

And finally, as this is serial and not USB, be patient because the transfer process can take a while!

Footnotes

1. “… or an alternative”: alternatives to Mapsource as an interface between a computer and the eTrex H are rare. GPSBabel is one example of which I have no personal experience. Most of Garmin’s other, higher specification devices are more simply managed since they feature removable memory cards ↑