Design an ALU that only adds
I'll give you a building block, the full adder, and how it is supposed to work in most cases:









simulate this circuit &ndash; Schematic created using CircuitLab



Now, what we are showing there is that the Sum voltage will be logic \$1\$ if only two out of three inputs are 1's. For the Carry, it outputs a 1 when at least 2 inputs are 1's. How would you make a chain of Full Adders to get the addition of the n-th bit and send its carry to the next unit?