anyone out there have an understanding of Gates & Circuits, and can help comparing two 2bit numbers to design a circuit or Boolean expression? It has been 16 years since I last set foot in a classroom. I've been working retail, management, for the last 10 years. It I had enough, it was time to go back to school. So I enrolled at Salem State and I'm back in school, looking to finish the degree I started. So I'm getting my degree in Computer Science and we are currently working with Gates, Circuits, Logic diagrams, and Boolean expressions. I figured out the two bit problems fine, I even felt confident figuring out the three bit issue. But I'm struggling with two 2 bit problems. Here's the problem I'm currently working on. Any help would be great. "Design a circuit that compares two 2 bit values for equality. That is, given values C and D, where C has two bits c1 and c0, & D has two bits d1 and d0. the output X, should be 1 if and only if C==D" if anyone can post the boolean expression or logic diagram that would be great. I'll be about to work backwords and figure out how it was designed and why. A little explanation would help. Thanks guys.