Abstract: There is disclosed a general purpose linear time division multiplexed conference system for continuously summing and supplying digital message samples arriving in time slots within a frame. The conference system integrates both voice and data network conference connections and provides total isolation between the secondary legs of a data network connection. The host computer of a data conference connection is assigned to the lowest ordered time slot relative to the time slots assigned to secondary legs of the data conference connection. The summation of data samples accumulated from each leg of the data conference connection during a write cycle is modified during a next supply cycle after distribution to the host computer but prior to distribution to secondary legs. Modification is achieved by overwriting the summation with the data sample received from the host computer during the prior write cycle.