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TODO: By analogy to the last circuit from Section 3, describe how thealuA,aluB, andfunctioninputs determine the value ofvalE– what does this value represent?TODO: By analogy to the last circuit from Section 3, describe how thealuA,aluB, andfunctioninputs determine the value ofvalO– what does this value represent?4
5Further AnalysisThe Concise Y86 ALU only has the functions to add, subtract, AND, and XOR.TODO (further analysis): Bymaking use of the relationships between multiplication/division and addition/subtraction, how couldthe Y86 ALU be used in a larger circuit to multiply numbers or divide numbers? If we were to buildthis larger circuit, what kind of components would we need? Why?6End of Lab SurveyTODO: To help us improve these labs both this term and for future offerings, complete the surveyhere.7Magic Box cleanupTODO: Before leaving the lab, show your Magic Box to your TA.AMarking schemeAll labs are out of ten marks, with two marks for pre-labs, and eight marks for in-lab work. In more detail:•Two marks - Pre-lab questions•Five marks - In-lab questions. In this lab, it is one mark for the demultiplexer implementation, one mark for themux-demux scheme, one mark for the multiplexing circuit, and two marks for the concise ALU questions.•One mark - Further analysis.•One mark - End of lab survey.•One mark - Magic Box cleanup.TAs may at their discretion award one bonus mark, such as for completing the challenge problem.5
BChallenge ProblemAddition is a basic operation in many ALUs. Using only basic logic gates (ie. AND, OR, XOR, NAND), design a circuitin Logisim that takes a 3-bit binary number and a 1-bit binary number and produces their sum (represented with 4bits). For instance, your circuit should output1000if given the inputs111and1, and it should output0110if giventhe inputs101and1.An example of the inputs and outputs:6