About GPS Files and Event Support  

• Converting GDB files to other formats
• About Routes, Tracks and Waypoints
• Why Updates
• GPS File Creation Info
• File Types
• GPS tips and quirks
• About the Data Source
• Feedback Wanted

 Converting GDB files to other formats…

GPSBABEL – the conversion tool of choice, so far!

I usually post Garmin GDB and Generic GPX format files on this site. If you have a need for a different file format, try downloading a format converter from the internet to produce the format of your choice.  Try GPSBabel, available at http://www.gpsbabel.org/ This program appears to handle over 150 different formats, the most I have seen on any converter to date.

Got a TomTom?  
In the past, we haven’t had any way to convert Garmin files to TomTom files.  Now, it appears that GPSBABEL will convert files into TomTom Itinerary (*.itn) files.  Not sure if it is direct from Garmin GDB files or from generic GPX files.  There’s also the question of whether your particular model will be able to use the result.  You will have to test. 

Whatever GPS you have, please leave a comment on what works or doesn’t, ok?

About Routes, Tracks and Waypoints….

Many people build track files.  These are simply a series of unnamed points along the route – often far more points than compared to a route. I’m trying to build files that will be most useful to a SAG vehicle, or any other event support person that has to DRIVE the course, so I have chosen to build ROUTE files. 

GPS Routes are built using WAYPOINTS.  I am creating WAYPOINTS that correspond as close as possible to the CUE SHEETS with as few additional WAYPOINTS as necessary.  Sometimes, I may add a few extra WAYPOINTS or even unnamed trackpoints to make sure that the GPS calculates the route from point to point and stays on track.  By using WAYPOINTS, this puts named locations into your GPS in case you need to plot a direct route to a specific location, particularly Rest Stops.

When there is a long distance between turns on a cue sheet, the route calculator engines in most GPS units tend to choose more “efficient” routes than the straight line between two cues because of GPS preference settings.  It will usually change the course to something faster, or to get off of sidestreets and onto major avenues.

In contrast, it is possible to generate TRACK files by actually driving the route and marking locations.  The upside is that  it is the most accurate representation of the course. The down side of that is that it inserts hundreds, perhaps thousands of track points in the trackroute.  Converting this to a ROUTE can be a pain, if not impossible, and can restrict their usefulness. Worse, certain GPS models have limits of a few hundred points or a small number of routes that can be imported. Another disadvantage is that many GPS units cannot use tracks to give directions — only to record a route already taken and only viewable as a map. In other words, no directions. 

My technique seems to be working for most of the people that use GPS units on these events. Please let me know what you think of this process and what can be done to improve it.

Why Updates?

Route creation is a tedious process.  Routes are built, then verified.  Mistakes are discovered and corrected.  Event sponsors make changes right up to the start of an event. Frequently, changes are made after the GPS files are built and before the event, so updates have to be generated. It is not always possible to get updates into the GPS files.

GPS File Creation Info

When I build GPS files for an event, I try to build a Master.GDB file first.  This file will contain all the route files for the event.  Next, I add in the reverse course files. These are primarily for the SAG volunteers. The master file will contain Waypoints for ALL routes involved.  The Master file will be a GDB file, a Garmin Database Ver. 3 file.  This seems to be the most popular, and is what my GPS uses. 

Next, I’ll generate a Master.GPX file.  This is the GPS eXchange Format standard used by most GPS manufacturers, so you should be able to load the data from that file.  If you need a different file type (see below), you can email me and request something specific.  Depending on time and complexity, I might generate the file and post it or send it to you.

Sometimes a big event will have multiple events on multiple days.  Many GPS units are limited on how many routes they can load at once. Mine holds 10 at a time.  In these cases, I will split the master file into multiple files. Commonly, this will result in two files, one for each day of a two day event.

File Types…

There are several different file types for GPS files.  I’m not completely up to speed, but I think I have a handle on them. I can generate the following formats:

• *.GPX — GPS eXchange Format files should be usable by most GPS units, no matter the manufacturer.
• *.GDB — Garmin GPS Database Versions 2 and 3.  GDB files are Garmin-specific database files.  I can produce version 2 or 3 files. 
• *.MPS — MPS Files
• *.TXT — Text (tab delimited)
• *.DXF — DXF files

Note: I don’t really know much about  the MPS or DXF files.  My first goal is to get the route files built and loaded into my database.  Once that is done, I can look at what types of files to create. If you need one of these types of files, let me know and I’ll see if I can post them to this website.

GPS Tips and Quirks

Some GPS units have glitches and problems built into them.  Others just don’t behave as expected or designed.  Here are some tips on stuff we’ve seen.

Can’t see all of the routes loaded. – Garmin 750 & 760

Many Garmin GPS units won’t load more than 10 routes at a time into active memory.  It will allow more to be loaded into the unit’s file memory though.  So far, I’ve been able to store at least 16 routes.  However, even after selecting 10 or less routes to load into memory, they may not all be visible after the load.  This happened to two of us, with a 750 and a 760 — loaded 8 routes, could only see 6.  When repeated, it was a different pair of routes that didn’t show.

The workaround that we found was only mildly painful.  We deleted the user data and reset the unit (hold thumb on lower right of screen while powering up) and reloaded the routes.  It worked fine after that.

About the data source….

The GPS and software that I am using are as follows:

As of:     August 10, 2010

GPS Side…

GPS:                       Garmin nuvi 760
Nuvi 7 Series s/w    Ver 4.90
GPS Software:        Ver. 2.90             
Basemap::              AMR Autoroute Basemap NR 2.00

Computer Software Side…

MapSource:            Ver. 6.16.2  
Map version:          City Navigator North America NT 2011.20

FEEDBACK WANTED

w4ft “at” w4ft(dot)com 

(edit the email address to normal format – I don’t need junk mail so I don’t post it here.)
Make sure that the files you download work in your GPS.  

Do it TODAY! Don’t wait until the day before the event
PLEASE email me and give me feedback!
There are lots of different GPS manufacturers and models.  These files may work with many, but maybe not with your GPS.  If  these files work with yours, please send me an email and tell me which files you used and the make, model and software versions of your GPS.

If these files don’t work with your GPS, let me know.  If you know why, let me know.  If you need a different format, let me know which of the following formats you need – GPX, GDB, MPS, TXT or DXF (see next section).  If you need another format, I can’t help, but maybe you can generate it from the GPX industry standard file.

The actual file generation is fairly quick, but subject to real world committments, so don’t expect a file if it is after sunset on the night before the event. Contrary to popular belief, I don’t live in front of my computer! Please, remember that working on these projects takes a lot of time, so I’ll do the best I can, but no promises.