Integrated Circuits Used 74LS74 Procedure Add IC 74LS74 into ICBase-3 (74LS74).Add IC 74LS74 into ICBase-4 (74LS74).Connect Input-5 to Pin-2 (Input) of ICBase-3 (74LS74).Connect Input-2 to Pin-4 (Input) of ICBase-3 (74LS74).