103 lines
4.1 KiB
Verilog
103 lines
4.1 KiB
Verilog
// -----------------------------------------------------------------------------
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//
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// Copyright 2013(c) Analog Devices, Inc.
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//
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// All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without modification,
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// are permitted provided that the following conditions are met:
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// - Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// - Redistributions in binary form must reproduce the above copyright
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// notice, this list of conditions and the following disclaimer in
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// the documentation and/or other materials provided with the
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// distribution.
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// - Neither the name of Analog Devices, Inc. nor the names of its
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// contributors may be used to endorse or promote products derived
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// from this software without specific prior written permission.
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// - The use of this software may or may not infringe the patent rights
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// of one or more patent holders. This license does not release you
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// from the requirement that you obtain separate licenses from these
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// patent holders to use this software.
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// - Use of the software either in source or binary form, must be run
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// on or directly connected to an Analog Devices Inc. component.
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//
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// THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR IMPLIED
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// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT, MERCHANTABILITY
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// AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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// IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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// INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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// -----------------------------------------------------------------------------
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// FILE NAME : debouncer.v
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// MODULE NAME : debouncer
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// AUTHOR : ACozma
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// AUTHOR'S EMAIL : andrei.cozma@analog.com
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// -----------------------------------------------------------------------------
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// KEYWORDS :
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// -----------------------------------------------------------------------------
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// PURPOSE : Module used for debouncing input signals
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// -----------------------------------------------------------------------------
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// REUSE ISSUES
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// Reset Strategy :
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// Clock Domains :
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// Critical Timing :
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// Test Features :
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// Asynchronous I/F :
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// Instantiations :
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// Synthesizable (y/n) : y
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// Target Device :
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// Other :
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// -----------------------------------------------------------------------------
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`timescale 1ns / 1ps
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module debouncer
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//----------- Paramters Declarations -------------------------------------------
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#(
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parameter DEBOUNCER_LEN = 4
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)
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//----------- Ports Declarations -----------------------------------------------
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(
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input clk_i,
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input rst_i,
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input sig_i,
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output reg sig_o
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);
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//------------------------------------------------------------------------------
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//----------- Registers Declarations -------------------------------------------
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//------------------------------------------------------------------------------
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reg [DEBOUNCER_LEN-1:0] shift_reg;
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//------------------------------------------------------------------------------
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//----------- Assign/Always Blocks ---------------------------------------------
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//------------------------------------------------------------------------------
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always @(posedge clk_i)
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begin
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if(rst_i == 1)
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begin
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shift_reg <= 0;
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sig_o <= 0;
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end
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else
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begin
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shift_reg <= {shift_reg[DEBOUNCER_LEN-2:0], sig_i};
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if(shift_reg == {DEBOUNCER_LEN{1'b1}})
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begin
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sig_o <= 1'b1;
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end
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else if(shift_reg == {DEBOUNCER_LEN{1'b0}})
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begin
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sig_o <= 1'b0;
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end
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end
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end
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endmodule
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