ON-SCREEN DISPLAY CIRCUIT OF DISPLAY APPLIANCE WITH CATHODE RAY TUBE

摘要

PURPOSE: An on-screen display circuit of a display appliance with a cathode ray tube is to transform a stored value of a control register in a row unit. CONSTITUTION: An interrupt circuit(10) comprises a first and second D flip-flops, a first to third inverters, and a first to third NAND gates. The first NAND gate(13) is inputted with an inverted signal of a vertical synchronizing circuit by the inverter and an output signal of a first D flip-flop(11) to output an output signal to a second NAND gate(16). A second D flip-flop(15) is inputted with an inverted signal of the vertical synchronizing circuit by a third inverter(18) as a reset signal to output an output signal to a third NAND gate(17). The second NAND gate is inputted with an output signal of the first NAND gate and the row signal of the second inverter to output a first interrupt signal.