Electronic charting without a serial port...
I have the same problem. My new computer does not have a 9 pin plug to connect my garmin gpsmap 76. I have tried 3 USB to 9 pin adapters. 2 of them supposedly where winxp compatable but had issues. I could not get the one that did not cause problems to be recocnised as a com port. I''m begining to think it would be easier to buy a sextant and take a class.
If you solve your problem, please let me know how you did it!!