Integrated Circuits Used 74HC191 Procedure Add IC 74HC191 into ICBase-4 (74HC191).Connect VCC Port to Pin-20 (VCC) of ICBase-4 (74HC191).Connect GND Port to Pin-8 (Ground) of ICBase-4 (74HC191).Connect Pin-1 (Input) of ICBase-4 (74HC191) to Input-1.