Author Topic: Another GPS question  (Read 2101 times)


  • Playing with a big steamy thing
Another GPS question
« on: 19 May, 2008, 07:15:36 am »
I have a Garmin E Trex Legend HC and I normally plan all my routes using Mapsource withe the Metro Gold add on ( Gives full Auto routing )

By way of experimentation I copied a route for the Stour 100 Kms and converted it to a Garmin file using GPS Babel.

All worked fine, except, it gave 891 "way points" and the Garmin is limited to a max of 250 when used in Route/off road mode.

Is their a simple way of getting round this ?

Chris S

Re: Another GPS question
« Reply #1 on: 19 May, 2008, 08:50:36 am »
Firstly, 891 points is a hell of a lot for a 100  :o.

Many 200's I've created routes for have had way points only for the controls - perhaps as few as five.

You need to differentiate between "way points" and "route points". I discovered recently, that when you create a way point in Map Source, it makes both a way point and a route point.

Try some experiments with a copy of your route. Open the gpx file in an editor and look to see if the points are both in the way points section and embedded in the route. If they are embedded in the route, you can delete the way points and the route points will still show up as you navigate the route.

I did a few experiments with a local 10km route and different ways of setting up a route, and have finally worked out a way that works for me.

Re: Another GPS question
« Reply #2 on: 19 May, 2008, 11:34:18 am »
It may have converted it to trackpoints, most Garmin GPSes have a trackpoint limit of 10,000. Trackpoints are just a log of a track. They don't interact with the routing system, or allow naming.

I've never tried navigating based on one, and I'm not sure if the arrow will keep pointing to the next point on the track.

So, imagine you've done the route once, if you look at the map page you'll see the log of where you've been. This is exactly what you get when you upload a tracklog. The idea is you follow the track on the screen to keep you on route.

(And, as I understand it, if you upload a track of 900 points you'll only have 9,100 trackpoints available for saving the tracklog of your actual ride).

[EDIT] If it was trackpoints then gpsbabel gives a way of filtering the number of trackpoints down to a more sensible number. See the gpsbabel docs...
"Yes please" said Squirrel "biscuits are our favourite things."