Patent GB-1394685-A (GB)
Title: System for charging telephone calls
IPC: H04M15/04
Filed: 1972-07-07
Abstract: 1394685 Telephone metering systems COMPAGNIE INDUSTRIELLE DES TELECOMMUNICATIONS CIT-ALCATEL 7 July 1972 [9 July 1971] 31940/72 Heading H4K A temporary metering store is associated with each or a group of markers each of which has an associated set of junctors in order to store details of and metering pulses appertaining to calls via the junctors. Call data in the store is transferred to a final bill processing station when the junctor via which the call extended is freed at the end of the call. In broad outline Fig. 1 (not shown) depicts a plurality P of miniprocessors each of which contains a metering store for handling calls via N junctors that are supervised by n markers. In the one miniprocessor shown, the junctors J1- JN have a buffer circuit RJ incorporating for each junctor four relays a, b, c, e indicative respectively of free/busy state, metering pulse present, call just finished (for enabling a data transfer from temporary to permanent store) and called party's number (as represented by dialling impulses); a marker buffer RM1 (one per marker) incorporating relays IM indicating a service demand condition, NJ a junctor's identity and NDr a caller's identity; a memory MP having ten rows per junctor; and a clock counter H, LM. The latter provides an output d tens, u units and memory row, for addressing the memory so as to effect a data processing operation thereon. When a junctor is first taken into use its controlling marker will be provided with its identity as well as with that of the caller so that the marker will present a service demand to its metering processor i.e. contact m closed. The counter LM, which scans all the junctors in turn, has its output translated at Td so as to determine the identity of the marker permanently associated with the currently scanned junctor. This identity g is compared at CG with the identities of demanding markers so that for the ease shown (Marker Mr1, contact m1) an output im1 is marked. The marking traverses a contact tree g indicative of the calling junctor's identity so that if this corresponds to the currently scanned junctor comparator CJ marks its output ij. Simultaneously logic LI 1  is enabled by a first row marking I thereby enabling gate P to pass a marking current through contact tree g1 in which is stored the first digit of the calling subscriber's number. This digit is transferred via logic LI1 into the first row of memory MP allocated to the currently scanned junctor (du). Further digits up to gx are transferred to the other memory rows as l is incremented by each clock pulse. When the junctor is next scanned its abce data is "analysed" by AN (this means that analogue voltages are converted into a form acceptable to the memory's logic circuitry) and for the case when this represents a called party's number it is passed via logic LI2 into an area of auxiliary memory MA allocated to the considered junctor whereas for the ease when it represents a metering pulse it is passed to logic LT which serves to increment the charge count stored in memory. At the end of a call the memory areas allocated to the considered junctor are cleared via logic LS into an output unit US. Since the operational speed of the latter is very slow MP and/or MA may be duplicated in whole or in part so as to accommodate new data from the junctor if this should be reseized on a new call before the data obtained therefrom on a previous call is fully unloaded.