| 摘要 |
PURPOSE:To self-diagnose a timing pulse system circuit pattern while a digital signal processing circuit is operated by providing plural detection means detecting timing pulses supplied to a digital signal processing part. CONSTITUTION:While a TV camera is in an operation state, the pulse detection circuits 410, 510 and 610 always operate. When respective D-FF 411-611 and 612 detect the rise of the respective pulses of a synchronism system timing signal Sts and a color synchronizing system timing signal Stc, they output '1' to terminals 413, 513, 614 and 615. When any of respective timing pulses is not detected, a detection flag corresponding to any of the terminals 413-615 is not raised and '0' is outputted. MPU 71 reads the detection flag leaving appropriate time from a CLR and judges the presence or absence of the supply of the corresponding timing pulse by the presence or absence of the detection flag. Thus, it is self-diagnosed whether the circuit pattern of the timing pulse system is normal or not. |
