FOERFARANDE OCH ANORDNING FOER ATT STYRBART UPPRAETTA KOMMUNIKATIONSFOERBINDELSER MELLAN PORTKRETSAR I ETT PCM-KOPPLINGSSYSTEM

摘要

A PCM switching system requires the assignment of either one or two time slots of a pair of time slots to a port circuit depending upon the type of service (voice only or voice plus data) each port circuit provides. Common resources normally assign a pair of time slots to each port circuit. This wastes time slots when the port circuit is used in a manner (voice only service) that requires only a single time slot. The disclosed arrangement eliminates the wasting of time slots by permitting the on-site reconfiguring of the system resources so that, when desired, only a single time slot can be assigned to a port circuit. This is accomplished by the removal of a first type of carrier control board that controls time slot distribution and by the substitution therefore of a second type of control board that applies the first time slot of a pair to its normally assigned port circuit and applies the second time slot of the same pair to another port circuit on the same carrier that also only requires a single time slot. This permits a given system to be configured initially in a first mode and then be subsequently reconfigured on-site so the port circuits of a carrier can each be assigned either one or two time slots. This arrangement avoids the wasting of time slots or costly on-site modifications as service needs change.