Video display processor having indication of sprite in excess of the

Abstract

A video display processor and video display system which overlays mobile patterns called sprites over a background. For each horizontal line the video display processor reads from an external memory data corresponding to sprites appearing on that line. This sprite data is loaded into N sprite registers. For each pixel in the horizontal line a display priority logic selects for display either the highest priority sprite or a background display if that pixel includes no sprites. If there are more than N sprites for a particular horizontal line, then an additional sprite status flag is set. The additional sprite status flag may be read by a host processor via a processor port. Reading the additional sprite status flag resets the flag. Each sprite includes a sprite number. An additional sprite number register is loaded with the sprite number of the N+1st mobile pattern on the horizontal line. This additional sprite number register may be read by a host processor via a processor port. In the preferred embodiment, the additional sprite status flag, the additional sprite number register and a sprite coincidence flag consist of respective bits of a host processors readable status register.