Force release of falsely engaged telephone exchange equipment - using search programme to interrogate associated equipment storage and release if not call held by processor working store

摘要

The system scans the store and checks busied storage compartments against the address code for calls in progress through the exchange. Any of these held and unrelated to calls in progress are force released so that the switch block equipment or peripheral equipment is force released at the same time. The method is partic. suitable for PABX central processor type exchanges. The search cycle to check the stores is only initiated if all stores are found to be busy during a call setup or if a long period of time has elapsed since a particular command has been used. The first call attempt through the exchange may fail due to busy storage compartments so the search programme is initiated to free falsely held ones so that the second attempt will succeed. The compartments in the working store are allocated to the control of the various exchange equipments used for call connection. The search programme involves forward and backward counting through the store.