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I am trying to build a 1-bit full adder that outputs a 2-bit sum.
I know that the standard 1-bit FA outputs a 1-bit sum and a carry bit, but I was wondering how can I modify the FA such that the carry bit output is discarded and the only output is a 2-bit sum.
You could feed the carry bit to another full adder that has zeroes on its other two inputs, but that seems kind of pointless because it will just get you a copy of the carry bit.
The carry bit is the second bit.
If you don't need a carry input you can just use a half adder.
So I looked up what constitutes a full adder and found its truth table.
Taken from wikipedia:
So you can see that if the adder has the correct output, your sum and carry bits are simply the 2 bit number you want. So I guess all the full adder really does is add up to 3 binaries at a time instead of 2.
