| 摘要 |
<p>PURPOSE:To provide a display controller capable of realizing a window function with a simple process without requiring large storage capacity and surely restoring an original image. CONSTITUTION:A storage area M1 for display image storing the image data corresponding to the display image and the storage area M2 for retreat capable of retreating the whole image data stored in the storage area M1 are provided in the memory space of a video RAM. When an initial window is set, the whole image data in the storage area M1 are retreated to the storage area M2 previous to the setting (see (b)). Thereafter, whenever the windows W1, W2 are set, the image data corresponding to these windows W1, W2 are overwritten in the storage area M1 for display image (see (c), (d)). When the setting of the windows W1, W2 are released, the image data in the storage area M2 are transferred to the storage area M1, and thus, the original image is restored.</p> |
