申論題

3. Figure 1 shows a 16-bit adder consisting of four 4-bit ALUs using carry lookahead. Assume that gi = ai bi (generate) and pi = aitbi (propagate). Determine the value of P0, P1, P2, P3, G0, G1, G2, G3, and C4 (CarryOut) when adding two 16-bit numbers 0001 1010001 1001 1 and 1110010111101011 with Carry_ In bit equal to 0. Please copy Table 3 to your answer sheet and fill in the blanks with your answers.