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// ========== Copyright Header Begin ==========================================

// 

// OpenSPARC T1 Processor File: sparc_exu_ecl_cnt6.v

// Copyright (c) 2006 Sun Microsystems, Inc.  All Rights Reserved.

// DO NOT ALTER OR REMOVE COPYRIGHT NOTICES.

// 

// The above named program is free software; you can redistribute it and/or

// modify it under the terms of the GNU General Public

// License version 2 as published by the Free Software Foundation.

// 

// The above named program is distributed in the hope that it will be 

// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

// General Public License for more details.

// 

// You should have received a copy of the GNU General Public

// License along with this work; if not, write to the Free Software

// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.

// 

// ========== Copyright Header End ============================================

////////////////////////////////////////////////////////////////////////

/*

//  Module Name: sparc_exu_cnt6

//      Description: 6 bit binary counter

*/

module sparc_exu_ecl_cnt6 (/*AUTOARG*/

   // Outputs

   cntr,

   // Inputs

   reset, clk, se

   ) ;

   input reset;

   input clk;

   input se;

   output [5:0] cntr;

   wire [5:0]   next_cntr;

   wire         tog1;

   wire         tog2;

   wire         tog3;

   wire         tog4;

   wire         tog5;

   assign       tog1 = cntr[0];

   assign       tog2 = cntr[0] & cntr[1];

   assign       tog3 = cntr[0] & cntr[1] & cntr[2];

   assign       tog4 = cntr[0] & cntr[1] & cntr[2] & cntr[3];

   assign       tog5 = cntr[0] & cntr[1] & cntr[2] & cntr[3] & cntr[4];

   assign next_cntr[0] = ~reset & ~cntr[0];

   assign next_cntr[1] = ~reset & ((~cntr[1] & tog1) | (cntr[1] & ~tog1));

   assign next_cntr[2] = ~reset & ((~cntr[2] & tog2) | (cntr[2] & ~tog2));

   assign next_cntr[3] = ~reset & ((~cntr[3] & tog3) | (cntr[3] & ~tog3));

   assign next_cntr[4] = ~reset & ((~cntr[4] & tog4) | (cntr[4] & ~tog4));

   assign next_cntr[5] = ~reset & ((~cntr[5] & tog5) | (cntr[5] & ~tog5));

   // counter flop

   dff_s #(6) cntr_dff(.din(next_cntr[5:0]), .clk(clk), .q(cntr[5:0]), .se(se), .si(), .so());

endmodule // sparc_exu_ecl_cnt6