| 摘要 |
PURPOSE:To prevent the destruction of a transmission/reception circuit and to recognize the abnormality of a transmission/reception switching signal by providing a transmission/ reception switching signal abnormality detection circuit provided with a transmission/reception circuit, a signal width summing circuit and a reference time count circuit, and an abnormality signal line sending an abnormality signal externally. CONSTITUTION:A signal width summing circuit 8, a reference time count circuit 7 of the transmission/reception signal abnormality detection circuit 1 detect an abnormality of a transmission/reception switching signal, an abnormality signal generating circuit 9 and a transmission/reception switching signal control circuit 10 receive a fault to make to the transmission/reception switching signal into a reception signal or a transmission signal only. Thus, if an abnormality transmission/reception switching signal is inputted to the transmission/ reception switching signal abnormality detection circuit 1, since the detection circuit 1 outputs a transmission/reception switching signal not destroying the transmission/reception circuit 2, the destruction of the transmission/reception circuit is prevented. Moreover, since an abnormality the transmission/reception circuit is prevented. Moreover, since an abnormality signal is outputted from the transmission/reception signal abnormality detection circuit 1 through an abnormality signal line 6, the abnormality of the transmission/reception switching signal is recognized even externally.
|
