Download the free shareware program, Waypoint+. Use WinZip or equivalent to extract the files. There is a good README file with the software.
You'll need a cable with an RS232 connector (DB-9 female) on one end and a Garmin plug on the other. (We have a cable for Frank's laptop at the field.) Cables are available from several sources: Wolfe's Cables makes this one. Alternatively, you can get a plug from Pplug and make your own following these instructions.
See the turnpoints page for current information, which is available with waypoints in several formats. From that page, save your file-format choice in the same directory as the Waypoint+ software, and return to this page. Be sure to save the file as plain text: right click on the link, then select "Save Target As," and complete the file dialog.
Turn on your Garmin 12, connect it via the cable to your computer's serial port, and check that the Garmin is configured as follows: select the MAIN-MENU, then select SETUP-MENU > INTERFACE. Now set the transfer protocol to GRMN/GRMN mode and set the function to HOST. These settings make the Garmin 12 act as a HOST, while Waypoint+ acts as a client that can send data to (upload waypoints) or receive data from (download tracks) the GPS.
Open Waypoint+, click OK on the acknowledgement screen, then click File > Open. Select and open the waypoint file you want. Choose "Waypoint Text or Route Point (TRK) Text File" as the file type from the file dialog box.
In Waypoint+ click GPS > Port and select your serial port, usually COM1. (You need to this only the first time.)
Clear existing waypoints from your Garmin 12 by selecting WAYPOINT-LIST from the MAIN-MENU page, then left (or right) arrow to select the DELETE-WPTS? option at the bottom of the screen. Follow the instruction to delete all of them.
Finally, click GPS > Upload-to-GPS > Waypoints. You can follow the progress on the Waypoint+ screen and on the Garmin's screen.
Unplug your Garmin and exit Waypoint+. You're done!
Larry Stephens
stephens at engr dot sc dot edu