Thursday 31 March 2005

I recently bought a Garmin Geko 201 GPS unit, which is rather neat. It came with no software, despite the fact that it boasts one of the better trackpoint memory capacities (for the budget models anyway) of 10,000 points. Thankfully there’s a lot of free stuff out there.

Rather thoughtfully Garmin provide the pin-outs for their propritary data connector, so I could rig up a serial cable from an old null modem cable and a matchstick. I downloaded my data to the PC in the GPX format using the handy GPSBabel tool.

Data transfer has not been a problem; there are more than enough tools to do that. The problem has been finding a decent tool to plot the data. For 2D, the best so far is Viking. It uses GTK, so works on the common platforms. The main problem is that it doesn’t accept GPX files, but only files in the GPSPoint format. There is a tool to grab data from Garmin units in this format, GPSPoint, but I had to compile the Windows binary as I couldn’t find a working link to any pre-compiled versions. Get my GPSPoint Windows binary here if you need it.

As far as I can tell, there is no 3D visualisation in Viking, so I’m still searching for a good realtime 3D GPS visualisation tool. It’s good, none-the-less, to be able to see exactly where I’ve been over the past few days. Hopefully I’ll be contributing my data to openstreetmap.org soon, after I’ve done a few more miles.