| 摘要 |
PURPOSE:To constitute a digital scan signal generator with a simple circuit by using the output signal of a timing control circuit for controlling the action of a counter circuit switching the number of dots or the number of scanning lines. CONSTITUTION:When a control circuit 7 reads that a blanking period starts based on the output data of a counter circuit, the circuit 7 feeds a signal informing that the blanking period starts to a driver circuit 3. Next, when the circuit 7 reads that the blanking period terminates, the circuit 7 feeds a preset signal to a horizontal scanning counter circuit 1. A vertical scanning counter circuit 2 counts horizontal blanking signals to feed them to a D/A converter 6. Likewise with the horizontal scanning, when the control circuit 7 reads that the vertical scanning enters the blanking period, it feeds a signal to a driver circuit 4, and during the blanking period, it feeds the same data as the initial value of the circuit 2 to the D/A converter 6. Accordingly, wide-range scanning can be covered with a single scanning circuit, and a scanning signal generator can be formed in a simple constitution. |
