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//////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2011, Andrew "bunnie" Huang
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation and/or
// other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
// SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
//////////////////////////////////////////////////////////////////////////////
`timescale 1 ps / 1ps
module decode_terc4 (
input clkin, // pixel clock input
input rstin, // async. reset input (active high)
input [9:0] din, // data inputs: expect registered
output reg [3:0] dout // data outputs
);
reg [9:0] din_r;
always @(posedge clkin or posedge rstin) begin
if( rstin ) begin
dout[3:0] <= 4'h0;
din_r <= 10'b0;
end else begin
din_r <= din;
case (din_r[9:0])
10'b1010011100: dout[3:0] <= 4'b0000;
10'b1001100011: dout[3:0] <= 4'b0001;
10'b1011100100: dout[3:0] <= 4'b0010;
10'b1011100010: dout[3:0] <= 4'b0011;
10'b0101110001: dout[3:0] <= 4'b0100;
10'b0100011110: dout[3:0] <= 4'b0101;
10'b0110001110: dout[3:0] <= 4'b0110;
10'b0100111100: dout[3:0] <= 4'b0111;
10'b1011001100: dout[3:0] <= 4'b1000;
10'b0100111001: dout[3:0] <= 4'b1001;
10'b0110011100: dout[3:0] <= 4'b1010;
10'b1011000110: dout[3:0] <= 4'b1011;
10'b1010001110: dout[3:0] <= 4'b1100;
10'b1001110001: dout[3:0] <= 4'b1101;
10'b0101100011: dout[3:0] <= 4'b1110;
10'b1011000011: dout[3:0] <= 4'b1111;
// no default to allow for maximum coding flexibility...
endcase // case (din_q)
end // else: !if( rstin )
end // always @ (posedge clkin or posedge rstin)
endmodule // decode_terc4
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