| 摘要 |
<p>Display control circuitry is provided which includes a frame buffer (104) having a plurality of memory spaces (301) each for storing a block of display data. Circuitry (200) is provided for generating display position data representing a position on a display screen corresponding to a current display pixel being generated. For each memory space (301), a window control circuit (201) is provided for controlling the transfer of a block of data from the given memory space (301) to a selected window on the display screen. Each window control circuit (201) includes first registers (205, 206) for storing data defining horizontal boundaries of the window, second registers (210, 211) for storing data defining vertical boundaries of the window, and circuitry (207, 208, 209, 212, 213, 214) for comparing the display position data with data stored in the first and second registers and generate an enable signal when the position on the screen of the current pixel is within the window boundaries. Memory control circuitry (300, 302) is provided for retrieving data from the memory space (301) selected in response to the enable signals received from the window control circuits (201).</p> |
