Problem Statement . I am trying to create a 12 bit counter with a combination of 4 bit counters (74191 Spec Sheet: http://pdf1.alldatasheet.com/datasheet-pdf/view/7831/NSC/74191.html) I cannot figure this out for he life of me. I'm honestly not understanding many of the circuits we have to build in my course. It's one of those situations where I don't know, for instance, what a "flip flop" is, and then I look it up on the net or in my text, and after reading, I still don't know what a flip flop is. I was able to assemble and test the counter (4 bits) but I do not know how to wire three to have a 12 bit counter. Attempt at a Solution I know that the RCO pin (13) should be connected to the enabler pin (4) of the next counter to signal it to start... In my diagram I have switches (S1, S2, etc....) connected to the pins 15, 1, 10, and 9 (the "inputs" )... the connection them are represented by the red wires... I am not sure how to deal with the input pins (A,B,C,D @ pins 15, 1, 10, and 9) of the next counter...should I just connect them all to the output pins QA, QB, QC, QD? I don't have a breadboard at the moment so I cannot test this, but I am trying to plan my circuit now and I'll assemble it in class.