Anyway, Garmins seem to me to have the most extensive support in the
freeware community, for some reason, but I don't really know what you
want to do to your chartplotter with your pc.

It just occured to me that most of the freeware I've seen is also
targeted at handhelds. I have no idea whether it will work with the
more expensive units.

It also occurs that you need to understand the different kinds of
connections. There is plain NMEA, used for getting position data from
the GPS to another instrument or the PC. For uploading and
downloading waypoints, routes, and tracks, you use a proprietary
format. A lot of the freeware is targeted at this proprietary
traffic.

Then there is the problem of attaching the GPS to the PC. I expect
that the chartplotter you select will not have a serial connector for
going straight to a PC, though many handhelds do. You will likely
want to buy an interface to convert the NMEA traffic to something the
PCs serial port will like. If you have more than one instrument to
hook up, you may want to invest in a multiplexor. At this point, I
have to confess to being unsure whether multiplexors handle the
proprietary protocol for waypoint upload, etc.



__________________________________________________ __________
Glen "Wiley" Wilson usenet1 SPAMNIX at worldwidewiley dot com
To reply, lose the capitals and do the obvious.

Take a look at cpRepeater, my NMEA data integrator, repeater, and
logger at http://www.worldwidewiley.com/