Call monitor for telecommunication exchange

Claim 1

A call monitor for an exchange serving a multiplicity of telecommunication lines through a set of line links which are periodically sampled by a scanner in respective time slots of a recurrent cycle for the establishment of connections therebetween by a switching network under the control of a central processor responsive to signals picked up from the sampled line links, comprising: a first memory with a multiplicity of phases respectively assigned to said line links for storing data relating to the activities thereof; programming means synchronized with said scanner for addressing successive phases of said first memory during time slots assigned to the sampling of the respective line links; a second memory containing a multiplicity of evolutionary codes identifying all possible states in the progress of a connection between subscriber lines coupled to respective line links; circuit means connecting said first memory with said processor for exchanging information therebetween; temporary storage means for incoming code signals indicative of the activity of a line link during a time slot assigned thereto; comparison means controlled by said programming means for reading out successive evolutionary codes from said second memory in the course of a time slot until the code signals entered in said temporary storage means match an evolutionary code thus read out, at least some of said evolutionary codes being accompanied in said second memory by instruction codes read out simultaneously therewith; output means connected to said second memory for storing an instruction code accompanying a matching evolutionary code; updating means connected to said output means and controlled by said programming means for inscribing the stored instruction code in a currently explored phase of said first memory as an activity information available during a subsequent cycle for starting the readout of evolutionary codes from said second memory; discriminating means connected to said output means for determining from the nature of the stored instruction code whether same is pertinent to said processor; and transfer means responsive to said discriminating means for relaying a pertinent instruction code to said processor.