Subversion Repositories rc4-prbs

/*

        RC4 PRGA Testbench

        Copyright 2012 - Alfredo Ortega

        aortega@alu.itba.edu.ar

 This library is free software: you can redistribute it and/or

 modify it under the terms of the GNU Lesser General Public

 License as published by the Free Software Foundation, either

 version 3 of the License, or (at your option) any later version.

 This library is distributed in the hope that it will be useful,

 but WITHOUT ANY WARRANTY; without even the implied warranty of

 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public

 License along with this library.  If not, see <http://www.gnu.org/licenses/>.

*/

`define RC4

`ifndef TEST_CYCLES

`define TEST_CYCLES 2000

`endif

`include "rc4.inc"

module rc4_tb;

reg [7:0] password[0:`KEY_SIZE-1];

parameter tck = 10, program_cycles = `TEST_CYCLES;

reg clk, rst; // clock, reset

wire output_ready; // output ready (valid)

wire [7:0] K; // output

reg [7:0] password_input; //input

/* Clocking device */

always #(tck/2)

        clk = ~clk;

/* Password loader and info display*/

integer clkcount;

always @ (posedge clk)

        begin

        clkcount<=clkcount+1;

        if (clkcount < `KEY_SIZE)

                begin

                password_input<=password[clkcount];

                $display ("--- clk %d --- key[%x] = %08X",clkcount,clkcount,password[clkcount]);

                end

        else $display ("--- clk %d --- K %08X --- valid: ",clkcount,K,output_ready);

        end

/* rc4 module implementation */

rc4 rc4mod(

        .clk(clk),

        .rst(rst),

        .password_input(password_input),

        .output_ready(output_ready),

        .K(K)

);

/* Simulation */

integer q;

initial begin

        for (q=0; q<`KEY_SIZE; q=q+1) password[q] = 8'h42; // initialize Key

        $display ("Start...");

        clk = 0;

        rst = 1;

        clkcount =0;

        password_input=password[clkcount];

        #(1*tck)

        rst = 0;

        #(program_cycles*tck+100)

        $display ("Finish.");

        $finish;

end

endmodule