The MC74HC164A is identical in pinout to the LS164. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LSTTL outputs. The MC74HC164A is an 8bit, serialinput to paralleloutput shift register. Two serial data inputs, A1 and A2, are provided so that one input may be used as a data enable. Data is entered on each rising edge of the clock. The activelow asynchronous Reset overrides the Clock and Serial Data inputs.