Can someone provide me with the proper way to load both topo maps on the Dakota 20. I downloaded the files from this site to mapsource. When I transfer the files to my micro card in the gps, it looks like they overwrite. I either have all the Arkansas topo info or all the Oklahoma topo info... not both... I can not find the other state's info to select. I have a 4 gb card in the unit. Any help would be appreciated.
You can do it by either:
1. Selecting some quads/tiles or all of one mapset. then doing so for another mapset - it will add them to the list in the left hand window; then sending all to the GPSr/memory card as a single gmapsupp.img file.
2. Send one mapset to the GPSr/memory card. rename the gmapsupp.img file to another name with a .img extension, i.e. ar_topo.img. Then do the same for additional mapset(s), i.e. ok_topo.img.
The second method is generally more flexable/usefull in the long term, but only works with the 'newer' models, and not all Nuvi.
See: http://www.gpsfiledepot.com/tutorials/how-to-load-maps-on-my-garmin-gps-unit/
Thanks for the info Maps4....