car_parking_system_tb.v

// car_parking_system_tb.v

`timescale 1ns/1ns  // Set the timescale for simulation

module tb_car_parking_system;

  // Inputs
  reg sensor1;
  reg sensor2;
  reg sensor3;
  reg sensor4;
  reg sensor5;
  reg sensor6;
  reg sensor7;
  reg sensor8;

  // Outputs
  wire [7:0] parking_spaces;

  // Instantiate the module under test
  car_parking_system uut (
    .sensors({sensor1, sensor2, sensor3, sensor4, sensor5, sensor6, sensor7, sensor8}),
    .parking_spaces(parking_spaces)
  );

  // File for VCD (Value Change Dump) output
  initial begin
    $dumpfile("car_parking_system_tb.vcd");
    $dumpvars(0, tb_car_parking_system);
  end

  // Initial block for stimulus generation
  initial begin
    // Test case 1: No cars, all spaces should be vacant
    sensor1 = 0;
    sensor2 = 0;
    sensor3 = 0;
    sensor4 = 0;
    sensor5 = 0;
    sensor6 = 0;
    sensor7 = 0;
    sensor8 = 0;
    #10;  // Wait for 10 time units
    // Expected output: parking_spaces = 00000000

    // Test case 2: Car in space 1, other spaces vacant
    sensor1 = 1;
    sensor2 = 0;
    sensor3 = 0;
    sensor4 = 0;
    sensor5 = 0;
    sensor6 = 0;
    sensor7 = 0;
    sensor8 = 0;
    #10;
    // Expected output: parking_spaces = 00000001

    // Test case 3: Car in space 2, other spaces vacant
    sensor1 = 0;
    sensor2 = 1;
    sensor3 = 0;
    sensor4 = 0;
    sensor5 = 0;
    sensor6 = 0;
    sensor7 = 0;
    sensor8 = 0;
    #10;
    // Expected output: parking_spaces = 00000010

    // Test case 4: Cars in spaces 1 and 2, other spaces vacant
    sensor1 = 1;
    sensor2 = 1;
    sensor3 = 0;
    sensor4 = 0;
    sensor5 = 0;
    sensor6 = 0;
    sensor7 = 0;
    sensor8 = 0;
    #10;
    // Expected output: parking_spaces = 00000011

    // Test case 5: Cars in spaces 7 and 8, other spaces vacant
    sensor1 = 0;
    sensor2 = 0;
    sensor3 = 0;
    sensor4 = 0;
    sensor5 = 0;
    sensor6 = 0;
    sensor7 = 1;
    sensor8 = 1;
    #10;
    // Expected output: parking_spaces = 11000000

    // Test case 6: Cars in spaces 1,3, 5 and 7, other spaces vacant
    sensor1 = 1;
    sensor2 = 0;
    sensor3 = 1;
    sensor4 = 0;
    sensor5 = 1;
    sensor6 = 0;
    sensor7 = 1;
    sensor8 = 0;
    #10;
    // Expected output: parking_spaces = 01010101

    // Test case 7: Cars in spaces 2, 4, 6 and 8, other spaces vacant
    sensor1 = 0;
    sensor2 = 1;
    sensor3 = 0;
    sensor4 = 1;
    sensor5 = 0;
    sensor6 = 1;
    sensor7 = 0;
    sensor8 = 1;
    #10;
    // Expected output: parking_spaces = 10101010

    // Test case 8: Cars in all spaces
    sensor1 = 1;
    sensor2 = 1;
    sensor3 = 1;
    sensor4 = 1;
    sensor5 = 1;
    sensor6 = 1;
    sensor7 = 1;
    sensor8 = 1;
    #10;
    // Expected output: parking_spaces = 11111111

    $stop;  // Stop simulation
  end

endmodule