http://www8.garmin.com/support/download_details.jsp?id=4469
Changes made from version 4.70 to 4.80:
- Changed battery charging mode to comply with new California energy regulations.
- Fixed an error that caused some SD cards to not be recognized.
- Fixed an error that caused the device to shut down with highly-detailed 3rd-party maps.
- Increased the length of a route that can be calculated in its entirety.