ALU Reference Model Using DPI in SystemVerilog Testbench

This repository contains the implementation of an Arithmetic Logic Unit (ALU) reference model in C, which is called from a SystemVerilog testbench using Direct Programming Interface (DPI). The ALU performs a variety of operations such as addition, subtraction, multiplication, division, and bitwise operations. The outputs from the C-based reference model are compared with the outputs from the Design Under Test (DUT), ensuring correct behavior of the ALU.

Overview

The project demonstrates the following:

1. C Reference Model: A simple ALU model implemented in C, which can handle 8-bit inputs and perform operations based on a 4-bit control signal (ALU_Sel).
2. DPI Integration: The ALU function in C is imported into the SystemVerilog testbench using DPI.
3. Testbench: The testbench compares the expected values from the C model with the actual output from the hardware ALU implemented in SystemVerilog.

Key Operations Performed by the ALU

• Addition
• Subtraction
• Multiplication
• Division
• Logical Shift (Left/Right)
• Rotate (Left/Right)
• Logical AND, OR, XOR, NAND, NOR, XNOR
• Comparisons (Equal, Greater Than)

Files in the Repository

• alu_reference_model.c:
  Contains the C implementation of the ALU model. This function is invoked from the SystemVerilog testbench via DPI.

• alu_tb.sv:
  The testbench that tests the ALU operations by calling the C function and comparing its results with the DUT output.

• alu.sv:
  SystemVerilog implementation of the ALU (Design Under Test).

• Makefile (optional):
  A Makefile for compilation and simulation, if applicable.

How It Works

1. The ALU operations are defined in the C function alu_reference_model.
2. This function is imported into the SystemVerilog testbench using DPI.
3. The testbench applies a set of test vectors to both the hardware ALU and the C reference model.
4. It compares the expected output from the C model with the actual output from the hardware ALU.
5. The results (pass/fail) for each test are printed in the simulation output.

Running the Simulation

1. Clone the repository:

   git clone https://github.com/yourusername/alu-dpi-verification.git