A wavefront array processor where each cell includes a handshake port for asynchronous data transfer with an adjacent cell. The handshake port includes a buffer for receiving data from the adjacent cell and a latch for transferring data to the adjacent cell. Data transfer is accomplished through use of a handshaking protocol which indicates whether or not a receiving buffer is full and if the buffer can receive data. Data can only be transferred if there is room in the buffer to accept the data. The handshaking protocol responds to status signals. A source status signal indicates that a data source has generated a data word. A sink status signal indicates that the buffer can receive data. Each cell further includes a data processing unit, which provides the latch with data and which accesses data from the buffer, and a blocking device, which allows the data processing unit or another handshake port to transfer data to the latch and the buffer to accept data, only when the handshake signals are appropriate. Internal to each cell is a ring bus configuration for distribution of data between the handshake ports and the data processing unit.