Integrated Circuits Used 74LS04 Procedure Connect Pin-6 (Input & Output) of ICBase-1 to GND Port.Add IC 74LS04 into ICBase-2 (74LS04).Connect Pin-7 (Ground) of ICBase-2 (74LS04) to GND Port.Connect Pin-20 (VCC) of ICBase-2 (74LS04) to VCC Port.