Firefishe wrote: ↑Mon Jul 18, 2022 12:51 am
Continuing this thread, what is the detailed reason why self-made OSM Maps will not work?
While a detailed response is well beyond the capacity of a forum post, I will offer a simple explanation.
Garmin devices do not identify maps using the map file names or even the map names internally coded into each map image. Instead, they use other unique identifiers that are hard coded into the map images themselves.
The map compiler software used by many OSM providers was created when City Navigator maps were the only real option for routable maps, and so each time they compile a new map release, the City Navigator ID is improperly coded into their maps.
When a Garmin device reads these improperly coded maps, they are incorrectly identified as City Navigator maps. This often results in undesirable behavior on devices equipped with advanced mapping and routing features. Garmin devices loaded with OSM maps that are correctly coded with OSM identification will not experience these issues.
Garmin devices that do not allow automobile/motorcycle routing with maps other than City Navigator will disable that feature when properly coded OSM maps are loaded, but will allow it when using OSM maps incorrectly coded as City Navigator maps.