Behavioral Description

BEHAVIORAL DESCRIPTION 

module decoder2_4 (y, I);

  input  [1:0] I;

  output [3:0] y;

  reg    [3:0] y;

  always @(I)

  begin

    case (I)

      2'b00: y = 4'b0001;

      2'b01: y = 4'b0010;

      2'b10: y = 4'b0100;

      2'b11: y = 4'b1000;

      default: y = 4'b0000;

    endcase

  end

endmodule

Test Bench:--

module tb_decoder2_4;

  reg  [1:0] I;

  wire [3:0] y;

 decoder2_4 uut (y, I);

  initial

  begin

    I = 2'b00;

    #10 I = 2'b01;

    #10 I = 2'b10;

    #10 I = 2'b11;

    #20 $finish;

  end

endmodule

OUTPUT