| 摘要 |
<p>PURPOSE:To simplify the display of multiple windows by deciding a display area from the address set at a controller corresponding to a window and the scan position of a CRT. CONSTITUTION:The parameters of the display start position of the display data stored in a RAM 8, the display start position to a CRT 11, the size of a display area, etc., are set at registers of controllers 1-4 corresponding to windows via a data setting circuit 14. The controllers 1-4 decide that a display area starts at a scan address of the CRT 11 and output active signals ON1-4, address signals ADD1-4, and valid component signals DE01-04 respectively. A selection circuit 5 outputs a selection signal SL based on the priority signal received from the circuit 14. The multiplexers 6 and 7 select one of signals ADD1-4 and DE01-04 respectively based on the signal SL and output the RAM address signal and the valid component signal DE.</p> |
