| 摘要 |
This invention relates to an image display system for reading out image data stored in an image memory and displaying the image data on multiple image planes and the vertical scrolling operation can be independently effected for each of the image planes displayed on the multiple image plane display basis. That is, assuming that two image planes are displayed on upper and lower areas, display starting addresses lying in the vertical direction of the upper and lower image planes and stored in registers are loaded into a counter via a switch in a display period of the upper and lower image planes to generate addresses in the vertical direction of the upper and lower image planes. The vertical scrolling operation only for one of the upper and lower image planes can be effected by sequentially updating the display starting addresses lying in the vertical direction of the upper and lower image planes and held in one of the registers.
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