| 摘要 |
PURPOSE:To make circuit size compact by calculating rewriting data on occasion at the time of inputting operation from a window operation part, storing the calculated result in a data FIFO and reading out the stored contents during the non-display period of a display part to rewrite a VLT. CONSTITUTION:In order to execute window conversion based upon operator's operation, the time required for the calculation of a window controller 8 is necessary and it is unnecessary to speed up, so that the calculation is executed on occasion on the basis of an operation input, rewriting data to be the calculated result are sequentially stored in a first-in first-out (FIFO) memory 9 and the oldest contents are successively read out from the memory 9 during the non-display period to rewrite a video look-up table (VLT) 4. Address similarly outputted from the window controller 8 may be stored in an address FIFO memory 10 as VLT 4 rewriting addresses or a presettable counter can be also used to rewrite all data in the table 4. |
