Electronics/ALU

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Contents

[edit] Arithmetic and Logic Unit

[edit] Introduction

The Arithmetic and Logic Unit are not a Single entity, but, are actually composed of two separate units, whose operation is highly dependent on the Select Input(S).

This input, is a one-bit input, that will decide whether to route the binary variables to the Arithmetic, or to the Logic Circuit.

[edit] Arithmetic Unit

Handles basic operations such as Addition and Subtraction. The Multiplication and Division operations are dependent on the basic operations, and Bit-Shifting. The Multiply and Divide operations, can also be implemented using Hardwired / Microprogrammed Control.

[edit] Logic Unit

The Logic unit, is a Hardware Unit, implemented for performing basic operations such as AND, OR, NAND, and NOT. A particular Logical Operation is selected using a 4:2 Demultiplexer.

The results of all the operations, are routed into a data bus, for memory addressing.

[edit] further reading