| 摘要 |
PURPOSE:To increase the speed of response to the state change of a terminal device by transmitting a multiplex transmitted wave cyclically from a central control panel to a terminal circuit and by driving the load of the terminal device by a supervision over the state of the terminal device and control over the terminal device. CONSTITUTION:With switches S1-S3, corresponding capacitors C1-C3 are charged by depressing state setting switches provided to terminal devices. Voltages developed according to the accumulation of charge are led to one terminal of AND gate 9 via the OR gate consisting of diodes D1-D3. At the other input terminal, on the other hand, AND gate 9 is supplied with a sent-back signal that determines sending-back timing to the central control office side. A pulse signal generated right after the sent- back signal is supplied to the base of transistor TR to discharge charged capacitors right after the signal is sent back. Threfore, the speed of response to a change in state improves. |
