SynchronousStack

Overview

This repository contains the implementation of a synchronous stack as part of a lab assignment for the Computer Architecture course. The stack has a 4-bit width per cell and supports several commands. The project includes both a Logisim schematic and a SystemVerilog description.

Project Structure

• logisim/: Contains the Logisim project files.
• systemverilog/: Contains the SystemVerilog files.

Commands

The stack supports the following commands, issued through the COMMAND input:

• 0 - nop: No operation.
• 1 - push: Push a value onto the stack.
• 2 - pop: Pop a value from the stack.
• 3 - get: Get a value from a specific stack index relative to the top.

Logisim Implementation

File: stack_logical.circ

The Logisim implementation is divided into several sub-circuits:

• Main Circuit (main): Contains only one instance of the stack sub-circuit and I/O elements for testing.
• Stack Circuit (stack): Implements the stack logic using sub-circuits for memory cells and control logic.

Elements Used

• Logic gates: NOT, OR, AND, NOR, NAND, XOR, XNOR
• Additional elements: Splitter, Probe, Tunnel, Transmission Gate (CMOS)

Usage

1. Open the .circ file in Logisim-evolution.
2. Simulate the circuit and test it using the input pins and probes.

SystemVerilog Implementation

Structural Model

• File: stack_structural.sv
• Module: stack_structural

Behavioral Model

• File: stack_behaviour.sv
• Module: stack_behaviour

Primitives Used

• Structural: PMOS, NMOS, CMOS, and basic logic gates (NOT, AND, NAND, OR, NOR, XOR, XNOR)
• Behavioral: Always blocks, initial blocks, assign statements, case statements, if statements

Usage

1. Compile the SystemVerilog files using Icarus Verilog.
2. Run the testbenches to verify the functionality of the stack.

Tools Required

• Logisim-evolution: Version 3.8.0 or later.
• Icarus Verilog: Version 10 or later (preferably 12).

How to Run

Logisim

1. Install Logisim-evolution.
2. Open the .circ file in Logisim-evolution.
3. Simulate the circuit.

SystemVerilog

1. Install Icarus Verilog.
2. Compile the SystemVerilog files:

   iverilog -o stack_behaviour_tb stack_behaviour_tb.sv stack_behaviour.sv
   vvp stack_behaviour_tb