Sony NVD-U12E Bedienungsanleitung Seite 6

For NV-U93T/U92T/U83/U82/U73T/U72T/U53/U52 users:
1
Select the transfer destination of the map data.
Note
The existing map data will be replaced when you select "nav-u Internal Memory."
2
If the transfer destination is set as "Memory Stick on PC," select
the drive corresponding to the "Memory Stick."
Tip
You can add the map data to a "Memory Stick" without any change to the map data in
the internal memory of the navigation unit.
6