these adders are what can set you off to making adders, i used them in my latest adder, if YOU used these, maybe you can make some without using a REAL counter in it, also making unlimited bit counters.
top, normal decimal 2 bit counter.
bottom, carry in on top input+ the top one.
the AND gates are used for carrying,
the XOR gates are for when an odd number is on for a one in the output but if its even its a zero because basically, it caryed all of it in binary that was in its spot.
