Moving map display

Disclosed is a moving map display having a mass memory storing a complete map of the terrain to be traversed by a vehicle, a scan memory storing a portion of the complete map corresponding to the area immediately surrounding the vehicle, a computer for controlling the updating of the portion of map stored in the scan memory and for controlling the refreshing of the map data displayed on a cathode ray tube display, a scan memory address generator receiving parameters computed by the computer for generating addresses sequential outputting the digital map data stored in the scan memory in a predetermined sequence, a video display generator for converting the map data output from the scan memory for utilization by the cathode ray tube display, and a timing generator for synchronizing the generation of the addresses by the scan memory address generator with the scan field of the cathode ray tube display.