Automatic repeated dialling facility for telephone pbx - has single chip programmable microprocessor communicating with central processor

摘要

In order to obtain an automatic repeated dialling facility in electronic telephone exchanges, the dialling signals from the subscriber (Tn) pass through the subscriber's equipment (TS) in the exchange, to the repeated dialling unit (WW). This contains a single-chip, programmed microcomputer (MC) with a accessible memory plates which the subscriber can use by means of a special code. The repeated dialling unit receives dialling details either direct or from the memory (As) of the central processor (ZVE) and sends appropriate instructions back to the central processor. Time and effort are saved in systems where the telephones are heavily used e.g. in private branch exchanges.