Mikhail sent in the following news item:1. Attach a GPS sensor/receiver with 2 wires to the GBA link port 2. Upload up to 20 maps of any size with the provided ROM maker/image calibration program3. The GBA will track the current position by smooth and fast scrolling of the map to hold the current position at the screen center and automatically switches between maps.http://www.msh-tools.com/GBA/gbagps.html