Assuming we are using a 2-function ALU which adds if the control input is 0 and subtracts B from A otherwise, and the input X is an 8-bit signed (twos complement) number, determine what the following circuit does:

NOTE: "this sends X to an ALU, ..." is not an answer. Write down what the output/function of the circuit is at a high-level. This applies to all such problems, as rewriting the circuit in English adds no information.

0 Sample Circuit