VERFAHREN FUER ZENTRALGESTEUERTE FERNMELDEVERMITTLUNGSANLAGEN MIT EINER ZENTRALEN PROGRAMMSTEUERUNG UND MIT TEILSTEUERUNGEN

摘要

The telephone switching system has a central program controller (ZS1) and subcontrollers (TSt, ASt, XSt) for driving passive circuit units (e.g. TS1, TS2). The task consists in preventing the corresponding passive switching units (e.g. TS1, TS2) from executing wrong functions in the case of malfunctioning of the subcontrollers (TSt, ASt, XSt). This is achieved by the switching states allocated to a faulty or faultless operation being stored in a switching state memory (e.g. SZS1) and the passive circuit units (e.g. TS1, TS2) being set to a function-free initial state in the case of malfunction. <IMAGE>