Telephone exchange fault diagnostic routine - receiving faults detected by central processor in excitation register for fault locating and separately storing according to fault type

摘要

The method of calling up the appropriate test programme is to check for faulty operation in a stored programme telephone exchange. The programme called up is decided by the type of fault condition being experienced. The programme indicates, after it has run, what measures should be adopted to remove the fault condition. When the common control (ZVE) equipment registers a fault condition it accesses the programme access register (ARF). A fault count is used to determine which diagnostic programme (A1, A2,..An) is used and gates (G4..Gn) are enabled as appropriate. At the end of the programme fault information (FI) output from the common control (ZVE) in conjunction with programme address and register controls (PZ,PR) outputs the data (FA).