| 摘要 |
<p>PURPOSE:To output display data to an image display device at a high speed by decreasing the necessary number of dual-port memories and making good use of good display data rewriting efficiency of the dual-port memories. CONSTITUTION:When the address of display data supplied into the image display controller from a CPU 1 is an address for an upper screen, the least significant digit bit of the row address counter of a memory address control part 7 is fixed at 0 and when the address of the supplied display data is an address for a lower screen, the least significant digit bit of the row address counter is fixed at 1, so that the display data for the upper screen of a two-divided screen panel and the display data for the lower screen can be held in a dual-port memory 15 alternately, line by line.</p> |
