Garmin Echomap compatability

I have a garmin echomap 70S marine unit and would love to access OSM on this unit.

Does anyone know how to get OSM to function in the garmin marine ECHOMAP devices

Any help would be appreciated

Maybe you can find some hints at

http://wiki.openstreetmap.org/wiki/OpenSeaMap_and_Garmin_nautical_chart_plotter ?