OziExplorer for the desktop will do that, then you can use the finished imported map with OziExplorerCE on your J720. Also Pocket Map Viewer will allow you to view map files on your Jornada too. In the screenshots below you see OziExplorer on top. You have to convert using the desktop program first though before you can view the maps on your HPC.
In the middle screenshot you see PocketMapViewer using a standard Garmin map image file. Again you would have to convert your Google maps or Trekking maps using the Garmap desktop software into a Garmin map compatible file.
Of course you know there is already a Google maps application that runs on some HPCs, or you can simply use the web browser and capture the Google Map image and view it on the built in image viewers...or using one of the dozens of graphic programs for viewing...like I did on the bottom screenshot. There is even an HPC version of Google Earth for the CE.NET devices that runs well.
(oziexplorer.jpg) (pocketmapviewer.jpg) (simplescreencapture.jpg) Attachments
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oziexplorer.jpg (21KB - 0 downloads) pocketmapviewer.jpg (179KB - 0 downloads) simplescreencapture.jpg (76KB - 0 downloads)