Verilog

Verilog is language commonly used in designing digital systems. It is a hardware description language, which means that it is substantially different from any other language you might have encountered so far. Even though it does have control flow statements and variables, it relies primarily on logic functions. It is a textual format for describing electronic circuits and systems.

Verilog has evolved as a standard hardware description language. Verilog offers many useful features for hardware design. It is easy to learn and easy to use as it is similar to C Programming language. Designers with C Programming experience will find it easy to learn Verilog.

ALU

This module explains how to design a Programmable 1-bit ALUusing Verilog. In computing, an arithmetic logic unit (ALU) is a digital circuit that performs arithmetic and logical operations. The ALU is a fundamental building block of the central processing unit of a computer, and even the simplest microprocessors contain one for purposes such as maintaining timers.

Most ALU's can perform the following operations:

• Bitwise logic operations (AND, NOT, OR, XOR)
• Integer arithmetic operations (addition, subtraction, and sometimes multiplication and division, though this is more expensive)
• Bit-shifting operations (shifting or rotating a word by a specified number of bits to the left or right, with or without sign extension). Shifts can be seen as multiplications and divisions by a power of two.

Inputs and Outputs

The inputs to the ALU are the data to be operated on (called operands) and a code from the control unit indicating which operation to perform. Its output is the result of the computation.