74HC/HCT7731 is a high-speed, single-pole, static shift register with recycling mode. Each register has independent data input pins Da to Dd, clock input pins CPa to CPd, and data output pins Qa to Qd. When the clock pulse changes from low to high, the data is shifted one place to the output end. Each recycling mode input controls two registers, RECab controls registers A and B, and RECcd controls registers C and D. When the REC input is high, the device is in the recycling mode and the data at the output end is shifted back to the input end of the register. This makes the data continuously repeated 64 times.
