81 lines
3.0 KiB
Verilog
81 lines
3.0 KiB
Verilog
// ***************************************************************************
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// ***************************************************************************
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// Copyright 2014 - 2017 (c) Analog Devices, Inc. All rights reserved.
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//
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// In this HDL repository, there are many different and unique modules, consisting
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// of various HDL (Verilog or VHDL) components. The individual modules are
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// developed independently, and may be accompanied by separate and unique license
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// terms.
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//
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// The user should read each of these license terms, and understand the
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// freedoms and responsabilities that he or she has by using this source/core.
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//
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// This core is distributed in the hope that it will be useful, but WITHOUT ANY
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// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
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// A PARTICULAR PURPOSE.
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//
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// Redistribution and use of source or resulting binaries, with or without modification
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// of this file, are permitted under one of the following two license terms:
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//
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// 1. The GNU General Public License version 2 as published by the
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// Free Software Foundation, which can be found in the top level directory
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// of this repository (LICENSE_GPL2), and also online at:
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// <https://www.gnu.org/licenses/old-licenses/gpl-2.0.html>
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//
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// OR
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//
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// 2. An ADI specific BSD license, which can be found in the top level directory
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// of this repository (LICENSE_ADIBSD), and also on-line at:
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// https://github.com/analogdevicesinc/hdl/blob/master/LICENSE_ADIBSD
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// This will allow to generate bit files and not release the source code,
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// as long as it attaches to an ADI device.
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//
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// ***************************************************************************
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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_LENGTH = 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_LENGTH-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_LENGTH-2:0], sig_i};
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if(shift_reg == {DEBOUNCER_LENGTH{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_LENGTH{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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