Control system for telex installation - uses discrete subroutines to regulate specific functions so that faults can be rapidly traced

摘要

The functioning of the exchange is controlled to permit easier supervision and fault finding. The control system forms a central unit of the exchange. The individual subroutines perform specific tasks such as scanning the subscribers, setting up connections, and calculating charges. The subroutines run serially, the completion of one calling up the start of the next. There is no interconnection between these routines, each being complete in itself. Thus any fault can readily be traced to a specific routine. The subroutines are normally under the control of a central processor, and individual units are buffered from each other.