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Switching registers to ALU

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• The multiplexor that you have just seen can be used to connect the registers to the ALU.

• Back in CS255, you should have learned about the internal organization of the ALU, not in a lot of details, but enough to know that there are general purpose registers that hold operands and results from operations, and an "Arithmetic and Logic Unit" (ALU) that does the *, /, +, - and other computations.

• My CS255 webpage on the CPU architecture can be found here: click here

• In CS355, you will learn exactly how the CPU works. The following is a taste of what's coming....

• The following circuit diagram shows how the registers are connected to the ALU (I will explain or have explained in class exactly how and why these connection are made):

  

• You can see how it works with the following logic-sim circuit program: click here