Captain Al and Navigation Software
I should have also said that for the extra $100 you get some 3D bottom contour charts that may, or may not be useful to you. Another features that may be useful now, or in the future is the AIS receiver that places commercial traffic information on the chart that shows the location, speed, direction, name, etc. of the vessel. I don't know if Great Lakes shipping is using AIS, but they are on the west coast. Most, if not all, of the top end programs will interface with the NMEA data of the AIS receiver. However if you choose to use more than one NMEA talker (GPS, AIS, auto pilot, speed log, wind direction/speed, etc.) you will need a multiplexer to "blend" the data from all of the NMEA talkers so the PC can sort it all out.jimq26, Roger said "free charts and software, that sounds to be my wants/needs". Garmin doesn't "give" anything away.