//------------------------------------------------------------------------------
//
// tb_lowlevel_adder47.v
// -----------------------------------------------------------------------------
// Testbench for 47-bit adder.
//
// Authors: Pavel Shatov
//
// Copyright (c) 2016, NORDUnet A/S
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// - Redistributions of source code must retain the above copyright notice,
//   this list of conditions and the following disclaimer.
//
// - Redistributions in binary form must reproduce the above copyright notice,
//   this list of conditions and the following disclaimer in the documentation
//   and/or other materials provided with the distribution.
//
// - Neither the name of the NORDUnet nor the names of its contributors may be
//   used to endorse or promote products derived from this software without
//   specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
//------------------------------------------------------------------------------


//------------------------------------------------------------------------------
`timescale 1ns / 1ps
//------------------------------------------------------------------------------


module tb_lowlevel_adder47;

   //
   // Inputs
   //
   reg				clk;
   reg [46: 0] 			a;
   reg [46: 0] 			b;

   //
   // Outputs
   //
   wire [46: 0] 		s;

   //
   // Test Vectors {a, b}
   //
   wire [93: 0] 		vec_0		= {47'h2a87ca22be8b, 47'h05378eb1c71e};
   wire [93: 0] 		vec_1		= {47'h7320ad746e1d, 47'h3b628ba79b98};
   wire [93: 0] 		vec_2		= {47'h59f741e08254, 47'h2a385502f25d};
   wire [93: 0] 		vec_3		= {47'h3f55296c3a54, 47'h5e3872760ab7};
   wire [93: 0] 		vec_4		= {47'h3617de4a9626, 47'h2c6f5d9e98bf};
   wire [93: 0] 		vec_5		= {47'h1292dc29f8f4, 47'h1dbd289a147c};
   wire [93: 0] 		vec_6		= {47'h69da3113b5f0, 47'h38c00a60b1ce};
   wire [93: 0] 		vec_7		= {47'h1d7e819d7a43, 47'h1d7c90ea0e5f};

   //
   // UUT
   //
   adder47_wrapper uut
     (
      .clk		(clk),
      .a		(a),
      .b		(b),
      .s		(s)
      );


   //
   // Testbench Routine
   //
   reg 			ok = 1;
   initial begin
      //
      clk = 0;
      //
      #100;
      //
      test_adder47(vec_0);
      test_adder47(vec_1);
      test_adder47(vec_2);
      test_adder47(vec_3);
      test_adder47(vec_4);
      test_adder47(vec_5);
      test_adder47(vec_6);
      test_adder47(vec_7);
      //
      if (ok)	$display("tb_lowlevel_adder47: SUCCESS");
      else	$display("tb_lowlevel_adder47: FAILURE");
      //
      $finish;
      //
   end


   //
   // Test Routine
   //
   reg	[46: 0]	ss;		// reference value of sum
   reg 		cc;		// reference value of carry
   reg 		ss_ok;	// result matches reference value

   task test_adder47;

      input	[93: 0] vec;

      begin

	 /* break down test vector */
	 a		= vec[93:47];
	 b		= vec[46: 0];

	 /* calculate reference values */
	 ss = a + b;

	 /* send one clock tick */
	 #10 clk = 1;
	 #10 clk = 0;

	 /* check outputs */
	 ss_ok = (s == ss);

	 /* display results */
	 $display("test_adder47(): %s", ok ? "OK" : "ERROR");

	 /* update global flag */
	 ok = ok && ss_ok;

      end

   endtask

endmodule

//------------------------------------------------------------------------------
// End-of-File
//------------------------------------------------------------------------------