RECEIVING SYSTEM OF PULSE CONTROLLED SIGNAL FOR KEY TELEPHONE DEVICE

摘要

PURPOSE:To ensure the stable reception of a pulse data, by forming a data format of transmission with a data pulse and a clock pulse, and detecting the clock pulse at the receiver side in the long and short periods. CONSTITUTION:The period A of sampling pulses SC1, SC1'-SCn is shorter than the clock pulse duration S. A period B covers a period from the detection of the 1st clock pulse CP1 through the 1st sampling pulse SC2' with which the detection is started for the 2nd clock pulse CP2. This period B is shorter than the period CT of the clock pulse, and the period C of the sum of periods A and B is longer than the period CT. Therefore the clock pulse is received with the period B when the basic oscillating frequency for the operation of the receiver side is set at a low level (b). While the clock pulse is received with the period C when the oscillating frequency is high (c). This ensures the stable reception of a data pulse.