Factorial Calculator in SystemVerilog

This repository contains a SystemVerilog-based implementation of a 32-bit factorial calculator. The project is divided into three main modules: datapath, FSM (Finite State Machine), and top. These modules work together to compute the factorial of a number using an iterative approach.

Features

• Datapath Module: Handles arithmetic operations and register management.
• FSM Module: Controls the flow of operations using a state machine.
• Top Module: Integrates the datapath and FSM modules and provides the testbench.

Modules

1. Datapath

The datapath module performs the following tasks:

• Maintains registers to store intermediate results.
• Provides multiplexers for selecting inputs to the ALU.
• Implements an ALU capable of subtraction and multiplication operations.
• Compares intermediate results to determine completion of the factorial calculation.

2. FSM (Finite State Machine)

The FSM module:

• Controls the states of the system: multiplication, subtraction, comparison, and completion.
• Generates control signals for the datapath based on the current state.

3. Top Module

The top module:

• Integrates the datapath and FSM modules.
• Provides a simple testbench for simulating the operation of the factorial calculator.

File Structure

• datapath.sv: Contains the datapath module.
• FSM.sv: Contains the FSM module.
• top.sv: Contains the top-level module and testbench.

Simulation

This project is designed to be simulated using any standard SystemVerilog simulator, such as ModelSim, XSIM, or Verilator.

Steps to Simulate

1. Clone this repository:

   git clone https://github.com/fahadhussain-1/Factorial_SystemVerilog.git

2. Open the project in your SystemVerilog simulation environment.
3. Compile the files in the following order:
   • datapath.sv
   • FSM.sv
   • top.sv
4. Run the simulation.
5. Observe the results and waveforms.

Control Signals

The following control signals are used in the design:

• a_sel and b_sel: Select inputs for the ALU.
• op_sel: Chooses between subtraction (1) and multiplication (0).
• w_sel: Selects which register to write to.
• w_en: Enables writing to the selected register.

Example Test Case

The testbench provided in the top module initializes the system and calculates the factorial of 5.

Output

The result of the calculation is stored in the Result output of the datapath module.

Dependencies

• A SystemVerilog simulation environment.

Future Enhancements

• Extend the design to handle larger numbers.
• Integrate this design with FPGA for hardware verification.

Contact

For any queries, reach out to:

• Fahad Hussain (Engineer) - [email protected]