Patent ID: 6864900

Claim:
A graphics system, comprising: a frame buffer configured to store an image; one or more display devices each configured to display a portion of an image; one or more raster parameter registers, wherein the raster parameter registers are configured to store a plurality of control values that specify what portion of the image will be displayed on a respective one of the display devices; one or more raster parameter register updaters, wherein each raster parameter register updater is configured to update a respective one of the raster parameter registers by waiting for a current frame or field to end and, once the current frame or field has ended, writing an updated control value to the respective one of the raster parameter registers; and one or more shadow registers, wherein each shadow register corresponds to a respective one of the raster parameter registers, and wherein each of the raster parameter register updaters is configured to update its respective raster parameter register by copying a value from each shadow register to a respective raster parameter register.