The CD4021BC is an 8-stage parallel input/serial output shift register. A parallel/serial control input enables individual JAM inputs to each of 8 stages. Q outputs are available from the sixth, seventh, and eighth stages. All outputs have equal source and sink current capabilities and conform to standard "B" series output drive. When the parallel/serial control input is in the logical "0" state, data is serially shifted into the register synchronously with the positive transition of the clock. When the parallel/ serial control is in the logical "1" state, data is jammed into each stage of the register asynchronously with the clock.