| 摘要 |
PURPOSE:To eliminate the need for an externally mounted folded connector by reflecting a signal from an output terminal to an input terminal via a passive element not requiring any reflecting control signal to check the input signal and the output signal through comparison thereby simplifying the diagnostic hardware. CONSTITUTION:An output signal S6 of a control circuit G of a logical device F is reflected to the control circuit G as an input signal S7 via a driver 14, a resistor R and a receiver 15. The control circuit G compares the output signal S6 with the input signal S7 so as to diagnose the interface circuit. Then a logical circuit I is connected via a cable H, the resistance value of the resistor R is selected to a proper value so as not to cause malfunction due to a crosstalk signal. Since it is impossible to diagnose the signal through reflecting by the resistor R, a diagnostic procedure is decided in a procedure making communication between the logical devices F and I via the cable H and the diagnosis is attained by mutual communication. |
