at_ctr2.v
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/**************************************************************************
* *
* Copyright (C) 1994, Silicon Graphics, Inc. *
* *
* These coded instructions, statements, and computer programs contain *
* unpublished proprietary information of Silicon Graphics, Inc., and *
* are protected by Federal copyright law. They may not be disclosed *
* to third parties or copied or duplicated in any form, in whole or *
* in part, without the prior written consent of Silicon Graphics, Inc. *
* *
*************************************************************************/
// $Id: at_ctr2.v,v 1.3 2003/01/15 03:34:09 berndt Exp $
////////////////////////////////////////////////////////////////////////
//
// Project Reality
//
// module: at_ctr2
// description: Counter for attribute buffers.
//
// designer: Phil Gossett
// date: 9/6/94
//
////////////////////////////////////////////////////////////////////////
module at_ctr2 (clk, rst, enb, z);
input clk;
input rst;
input enb;
output z;
reg z;
// counter
always @(posedge clk)
begin
if (rst == 1'b0)
z <= 1'b1; // -1
else
z <= enb ? !z : z;
end
endmodule // at_ctr2