| 摘要 |
PURPOSE:To realize a clear display image, and simplify the constitution of hardware by making a CPU to receive offering by taking advantage of the blanking signal of an electric scanning circuit, and carrying out necessary regulation by reading changes of set value which are caused by an operational switch or the like. CONSTITUTION:An electronic scanning circuit is controlled by a CPU through an interface circuit 12, and gives deflecting voltage to a scanning coil 3. Next, scanning speed signals set in an operational part 14 are fed to the inputs of a vertical-scanning-signal generator 200, and integrated 30 to deliver a blanking signal (PB), which is given to an OR circuit 33 and a change-over circuit 40. Then, the output of the circuit 33 is fed to the inputs of an integral reset circuit 33, while the output of the circuit 40 is fed to the inputs of an offering-signal generating circuit 41. Next, the circuit 40, which is given blanking signals (PB') of a horizontal-scanning signal generating part 100, gives the CPU an offering signal (Pi) through the circuit 12 after the signals (PB') undergo automatic selection. After that, the CPU rceives the signal (Pi), reads the set information of each operational switch, and performs processing according to the set changes. At this point, a CRT9 is compulsorily turned into a blanking condition through the circuit 33 or 23. |
