Abstract: An interactive communications channel (ICC) for providing a digital computer with high-performance multi-channel interfaces. Sixteen full duplex channels can be serviced in the ICC with the sequence or scan pattern being programmable and dependent upon the number of channels and their speed. A channel buffer system is used for line interface, and character exchange. The channel buffer system is on a byte basis. The ICC performs frame start and frame end functions, bit stripping and bit stuffing. Data is stored in a memory in block format (256 bytes maximum) by a program control and the ICC maintains byte address information and a block byte count. Data exchange with the memory is made by cycle steals. Error detection is also provided for using a cyclic redundancy check technique.

Abstract: Buffer division matrix for multiplexing and demultiplexing information signals in a communication system. A controller network controls information flow through a memory shared with a processor. The shared memory and the controller network comprise the buffer matrix, operating as a buffer division circuit switch and as a dynamic multiplexer/demultiplexer for high speed trunks. The buffer matrix is coupled to the processor as if the matrix were a memory. A control memory contains information about each subscriber and trunk to be serviced by the buffer matrix, information to control channel scan, and the characteristics of each channel. The control memory is initialized by the processor. Subscanning is implemented to increase the efficiency of the system.