Abstract: An arrangement for controlling switch connections (115) between a plurality of accessing circuits (113a through 113n) and a plurality of peripheral circuits (116) prevents simultaneous connections by more than one accessing circuit to any one peripheral circuit. Address signals which identify requested connections are decoded to generate connection request signals. A resistor network (501A through 501N and 506A through 506N) responsive to the connection request signals generates voltage level signals representative of the number of accessing circuits requesting connection to each peripheral circuit. The voltage level signals are compared to a threshold signal to generate a connection enable signal if only one accessing signal is requesting connection to a given peripheral circuit and to generate a busy signal if more than one accessing circuit is requesting connection to a given peripheral circuit. Switch connections are completed only after receiving a connection enable signal.

Abstract: A message storage system (104) deletes leading silence from messages to be stored therein. Voice messages are converted to digital signals and stored as data blocks in a digital memory (601). Voice signals are detected in messages to be stored and a voice present signal is generated during periods of time when voice signals are detected. The memory is set to a starting location after the storage of each group of four data blocks of a message until a voice present signal is generated, thereby deleting leading data blocks which do not contain voice signals.

Abstract: An arrangement tears down existing connection paths in a two stage switching network wherein switching paths are set up progressively by control circuits in both switching stages. A first-stage setup command is received by a first-stage control circuit and the second-stage control circuit of the previously established connection path. The first-stage control circuit responds to the first-stage setup command to set up a connection path through the first-stage switch and the second-stage control circuit responds to the first-stage setup command to tear down the previously established connection path.