HD74HC298

This HD74HC298 circuit is controlled by the signals word select and clock. When the word select input is taken low word 1 (A₁, B₁, C₁ and D₁) is presented to the inputs of the flip-flops, and when word select is high word 2 (A₂, B₂, C₂ and D₂) is presented to the inputs of the flip-flops. The selected word of HD74HC298 is clocked to the output terminals on the negative edge of the clock pulse.