Abstract: A time division communication system having peripheral devices controlled om a port circuit is arranged such that the port circuit may have assigned to it a variable number of time slots for any peripheral device associated therewith. Each port circuit has a microprocessor control device which is capable of controlling communication to or from the port circuit over the system time division bus or to and from the port circuit and the peripheral over a variable number of time slots, none of which are preassigned to the port circuit.

Abstract: A transient power alarm is often the result of a traffic overload placed on a communication system circuit carrier circuit. The disclosed power control arrangement recognizes such transient power alarms and outputs a special message to alert the system user to the possibility that traffic grading across carrier is unbalanced. The control arrangement also monitors the time that the system is powered solely by reserve battery and sheds its traffic load if the time that the system is operating solely on reserve battery exceeds a first threshold. Also, the system is programmed to automatically disable itself if the reserve battery time exceeds a second threshold.

Abstract: In time division communication systems one conference technique is to have a processor combine those samples going to a particular station forming a conference having as many subcombinations as there are stations. This approach, while allowing individual station gain adjustment, suffers from its dependence upon a large number of logic operations for a given conference. A modification of this technique is disclosed which uses a distributed structure such that the individual station ports, under local memory and processor control, operate to combine selected time slot samples into a conference sum unique to the station. In this manner gain values may be assigned on an individual listener station basis while the logic processing for the conference is performed in parallel by the ports involved in the conference.

Abstract: A transmission arrangement for use in a customer premises communication system is operable for controlling transmission during the MF digit signaling interval in situations where it is necessary to convert station dialed MF signals to pulsed digit signaling. In systems where the signaling station, the MF to dial pulse converter and the Central Office or PBX line are bridged on the same communication link it is possible for the station's MF signals to be detected by the MF receiver in the Central Office, thereby causing errors in the received digits. These problems are eliminated by inserting two transmission gates in the four-wire portion of the CO line. The gates are controlled by the processor in the customer premises communication system such that the outward gate is opened immediately upon seizure of the line by the calling station and remains open during the entire dialing interval.