| 摘要 |
PURPOSE:To substitute a dial signal for a hooking operation, by converting a dial pulse signal to a signal having the width of a hooking signal with hardware in a subscriber loop monitor circuit. CONSTITUTION:In a subscriber loop monitor circuit, a hooking signal is detected with a dial signal by selecting either one of the output signal of a means, which generates pulses having a certain time width and are operated by the loop disconnection due to a dial pulse or hooking, and the dial pulse in a state discriminating means which discriminates the dial pulse counting state or the busy state. In the state discriminating means is executed to expaud EXP the order from a control program and to set a flip flop FF to discriminate the state. Pulses having a certain time width operated by the loop disconnection are generated by a monostable multivibrator MM. On a basis of the state of the FF, a selecting circuit SEL selects either one of the dial pulse and the pulses having a certain time width. |
