The CD4021BC is an 8-stage parallel input/serial outputshift register. A parallel/serial control input enables individualJAM inputs to each of 8 stages. Q outputs are availablefrom the sixth, seventh, and eighth stages. All outputs haveequal source and sink current capabilities and conform tostandard “B” series output drive.When the parallel/serial control input is in the logical “0”state, data is serially shifted into the register synchronouslywith the positive transition of the clock. When the parallel/serial control is in the logical “1” state, data is jammed intoeach stage of the register asynchronously with the clock.