Electronics/ALU
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[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.
