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Konstantin Pavlov (pt) 40533743d7 Added altera cookbook
2015-12-15 22:44:58 +03:00

92 lines
2.8 KiB
Verilog

// Copyright 2007 Altera Corporation. All rights reserved.
// Altera products are protected under numerous U.S. and foreign patents,
// maskwork rights, copyrights and other intellectual property laws.
//
// This reference design file, and your use thereof, is subject to and governed
// by the terms and conditions of the applicable Altera Reference Design
// License Agreement (either as signed by you or found at www.altera.com). By
// using this reference design file, you indicate your acceptance of such terms
// and conditions between you and Altera Corporation. In the event that you do
// not agree with such terms and conditions, you may not use the reference
// design file and please promptly destroy any copies you have made.
//
// This reference design file is being provided on an "as-is" basis and as an
// accommodation and therefore all warranties, representations or guarantees of
// any kind (whether express, implied or statutory) including, without
// limitation, warranties of merchantability, non-infringement, or fitness for
// a particular purpose, are specifically disclaimed. By making this reference
// design file available, Altera expressly does not recommend, suggest or
// require that this reference design file be used in combination with any
// other product not provided by Altera.
/////////////////////////////////////////////////////////////////////////////
// baeckler - 7-20-2006
module ecc_2bit_tb ();
reg [1:0] dat;
wire [5:0] code;
reg [5:0] err;
wire [5:0] damaged_code;
wire [1:0] recovered;
wire [2:0] err_flag;
// encode - corrupt - decode
ecc_encode_2bit enc (.d(dat), .c(code));
assign damaged_code = code ^ err;
ecc_decode_2bit dec (.c(damaged_code),.d(recovered), .err_flag (err_flag));
integer n,i,j;
initial begin
// test the four no-error cases
for (n=0; n<4; n=n+1) begin
dat = n[1:0];
err = 0;
#1
// you must recover data and flag no-error
if ((recovered !== dat) || (err_flag !== 3'b001)) begin
$display ("Mismatch in no-error cases");
$stop();
end
end
// test the twenty four one-error cases
for (n=0; n<4; n=n+1) begin
for (i=0; i<6; i=i+1) begin
dat = n[1:0];
err = 1'b1 << i;
#1
// you must recover the data and flag correctly
if ((recovered !== dat) || (err_flag !== 3'b010)) begin
$display ("Mismatch in one-error cases");
$stop();
end
end
end
// test the (144? but overlapping) two-error cases
for (n=0; n<4; n=n+1) begin
for (i=0; i<6; i=i+1) begin
for (j=0; j<6; j=j+1) begin
if (j != i) begin
dat = n[1:0];
err = 1'b1 << i;
err = err | (1'b1 << j);
#1
// you must flag correctly
if (err_flag !== 3'b100) begin
$display ("Mismatch in two-error cases");
$stop();
end
end
end
end
end
#10 $display ("PASS");
$stop();
end
endmodule