| 1 | 4 | rudi | /////////////////////////////////////////////////////////////////////
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         | 2 |  |  | ////                                                             ////
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         | 3 |  |  | ////  WISHBONE Memory Controller                                 ////
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         | 4 |  |  | ////  Parametarized, Pipelined Incrementer                       ////
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         | 5 |  |  | ////                                                             ////
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         | 6 |  |  | ////                                                             ////
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         | 7 |  |  | ////  Author: Rudolf Usselmann                                   ////
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         | 8 |  |  | ////          rudi@asics.ws                                      ////
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         | 9 |  |  | ////                                                             ////
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         | 10 |  |  | ////                                                             ////
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         | 11 |  |  | ////  Downloaded from: http://www.opencores.org/cores/mem_ctrl/  ////
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         | 12 |  |  | ////                                                             ////
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         | 13 |  |  | /////////////////////////////////////////////////////////////////////
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         | 14 |  |  | ////                                                             ////
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         | 15 | 22 | rudi | //// Copyright (C) 2000-2002 Rudolf Usselmann                    ////
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         | 16 |  |  | ////                         www.asics.ws                        ////
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         | 17 |  |  | ////                         rudi@asics.ws                       ////
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         | 18 | 4 | rudi | ////                                                             ////
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         | 19 |  |  | //// This source file may be used and distributed without        ////
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         | 20 |  |  | //// restriction provided that this copyright statement is not   ////
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         | 21 |  |  | //// removed from the file and that any derivative work contains ////
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         | 22 |  |  | //// the original copyright notice and the associated disclaimer.////
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         | 23 |  |  | ////                                                             ////
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         | 24 |  |  | ////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////
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         | 25 |  |  | //// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////
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         | 26 |  |  | //// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////
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         | 27 |  |  | //// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////
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         | 28 |  |  | //// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////
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         | 29 |  |  | //// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////
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         | 30 |  |  | //// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////
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         | 31 |  |  | //// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////
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         | 32 |  |  | //// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////
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         | 33 |  |  | //// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////
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         | 34 |  |  | //// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////
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         | 35 |  |  | //// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////
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         | 36 |  |  | //// POSSIBILITY OF SUCH DAMAGE.                                 ////
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         | 37 |  |  | ////                                                             ////
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         | 38 |  |  | /////////////////////////////////////////////////////////////////////
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         | 39 |  |  |  
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         | 40 |  |  | //  CVS Log
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         | 41 |  |  | //
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         | 42 | 22 | rudi | //  $Id: mc_incn_r.v,v 1.2 2002-01-21 13:08:52 rudi Exp $
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         | 43 | 4 | rudi | //
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         | 44 | 22 | rudi | //  $Date: 2002-01-21 13:08:52 $
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         | 45 |  |  | //  $Revision: 1.2 $
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         | 46 | 4 | rudi | //  $Author: rudi $
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         | 47 |  |  | //  $Locker:  $
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         | 48 |  |  | //  $State: Exp $
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         | 49 |  |  | //
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         | 50 |  |  | // Change History:
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         | 51 |  |  | //               $Log: not supported by cvs2svn $
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         | 52 | 22 | rudi | //               Revision 1.1  2001/07/29 07:34:41  rudi
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         | 53 |  |  | //
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         | 54 |  |  | //
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         | 55 |  |  | //               1) Changed Directory Structure
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         | 56 |  |  | //               2) Fixed several minor bugs
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         | 57 |  |  | //
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         | 58 | 4 | rudi | //               Revision 1.1  2001/06/12 15:18:47  rudi
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         | 59 |  |  | //
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         | 60 |  |  | //
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         | 61 |  |  | //               This is a pipelined primitive incrementor.
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         | 62 |  |  | //
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         | 63 |  |  | //
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         | 64 |  |  | //
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         | 65 |  |  | //
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         | 66 |  |  | //
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         | 67 |  |  |  
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         | 68 |  |  | `include "mc_defines.v"
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         | 69 |  |  |  
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         | 70 |  |  | //
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         | 71 |  |  | // USAGE: incN_r #(<WIDTH>) uN(clk, input, output);
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         | 72 |  |  | //
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         | 73 |  |  | module mc_incn_r(clk, inc_in, inc_out);
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         | 74 |  |  |  
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         | 75 |  |  | parameter       incN_width = 32;
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         | 76 |  |  |  
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         | 77 |  |  | input           clk;
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         | 78 |  |  | input   [incN_width-1:0] inc_in;
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         | 79 |  |  | output  [incN_width-1:0] inc_out;
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         | 80 |  |  |  
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         | 81 |  |  | parameter       incN_center = incN_width / 2;
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         | 82 |  |  |  
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         | 83 |  |  | reg     [incN_center:0]          out_r;
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         | 84 |  |  | wire    [31:0]                   tmp_zeros = 32'h0;
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         | 85 |  |  | wire    [incN_center-1:0]        inc_next;
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         | 86 |  |  |  
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         | 87 |  |  | always @(posedge clk)
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         | 88 |  |  |         out_r <= #1 inc_in[incN_center - 1:0] + {tmp_zeros[incN_center-2:0], 1'h1};
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         | 89 |  |  |  
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         | 90 |  |  | assign inc_out[incN_width-1:incN_center] = inc_in[incN_width-1:incN_center] + inc_next;
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         | 91 |  |  |  
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         | 92 |  |  | assign inc_next = out_r[incN_center] ?
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         | 93 |  |  |                         {tmp_zeros[incN_center-2:0], 1'h1} : tmp_zeros[incN_center-2:0];
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         | 94 |  |  |  
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         | 95 |  |  | assign inc_out[incN_center-1:0]  = out_r;
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         | 96 |  |  |  
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         | 97 |  |  | endmodule
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         | 98 |  |  |  
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