| 摘要 |
PURPOSE:To select a required display control signal automatically by giving a 1st display control signal and a 2nd display control signal to a changeover circuit depending whether a video signal adopts the interlace system or the non-interlace system. CONSTITUTION:A 1st display control signal S3 generated from the interlace system vertical synchronizing signal and a 2nd display control signal S5 generated from the noon-interlace system vertical synchronizing signal are fed to a changeover circuit 4. On the other hand, a switching S4 corresponding to the interlace system and the non-interlace system is obtained by a flip-flop circuit 5 and an exclusive OR gate 6. That is, when a video signal S1 is the interlace system, an output terminal Q3 of the flip-flop circuit 5 provides an H level signal, the changeover circuit 4 is set to the position (a) and the 1st display control signal S3 is selected. When a video signal S1 is the non-interlace system, an output terminal Q3 of the flip-flop circuit 5 provides an L level signal, the changeover circuit 4 is set to the position (b) and the 2nd display control signal S5 is selected. |
