| 摘要 |
A circuit arrangement is provided for digital telephone stations in a digital private branch exchange, whereby control information are constantly exchanged via a subscriber line. The telephone station is controlled by a constantly interrogating and controlling microprocessor. The microprocessor can, for example, be arrested by a disturbing pulse. The invention provides the creation of a simple possibility of providing a reset pulse in an out-of-order case of the microprocessor. This is achieved in that repeated actuation of the cradle switch contact in brief succession charges the capacitor, due to multiple charging surges, the reaches the threshold voltage at the base of the transistor that is needed for this transistor, whereby the transistor is activated and generates the reset pulse.
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