se_pa_tst.tfw

这是我自己写的4位并转串ISE代码

////////////////////////////////////////////////////////////////////////////////
// Copyright (c) 1995-2003 Xilinx, Inc.
// All Right Reserved.
////////////////////////////////////////////////////////////////////////////////
//   ____  ____ 
//  /   /\/   / 
// /___/  \  /    Vendor: Xilinx 
// \   \   \/     Version : 8.1i
//  \   \         Application : ISE
//  /   /         Filename : se_pa_tst.tfw
// /___/   /\     Timestamp : Mon Nov 06 20:53:57 2006
// \   \  /  \ 
//  \___\/\___\ 
//
//Command: 
//Design Name: se_pa_tst
//Device: Xilinx
//
`timescale 1ns/1ps

module se_pa_tst;
    reg se_in = 1'b0;
    wire [3:0] pa_out;
    reg clr = 1'b1;
    reg clk = 1'b0;

    parameter PERIOD = 200;
    parameter real DUTY_CYCLE = 0.5;
    parameter OFFSET = 0;

    initial    // Clock process for clk
    begin
        #OFFSET;
        forever
        begin
            clk = 1'b0;
            #(PERIOD-(PERIOD*DUTY_CYCLE)) clk = 1'b1;
            #(PERIOD*DUTY_CYCLE);
        end
    end

    se_pa UUT (
        .se_in(se_in),
        .pa_out(pa_out),
        .clr(clr),
        .clk(clk));

    integer TX_FILE = 0;
    integer TX_ERROR = 0;
    
    initial begin  // Open the results file...
        TX_FILE = $fopen("results.txt");
        #1200 // Final time:  1200 ns
        if (TX_ERROR == 0) begin
            $display("No errors or warnings.");
            $fdisplay(TX_FILE, "No errors or warnings.");
        end else begin
            $display("%d errors found in simulation.", TX_ERROR);
            $fdisplay(TX_FILE, "%d errors found in simulation.", TX_ERROR);
        end
        $fclose(TX_FILE);
        $stop;
    end

    initial begin // Process for clk
        // -------------  Current Time:  85ns
        #85;
        se_in = 1'b1;
        // -------------------------------------
        // -------------  Current Time:  285ns
        #200;
        se_in = 1'b0;
        // -------------------------------------
        // -------------  Current Time:  485ns
        #200;
        se_in = 1'b1;
        // -------------------------------------
        // -------------  Current Time:  885ns
        #400;
        se_in = 1'b0;
        // -------------------------------------
    end

    initial begin // Process for Asynchronous Signals
    end

    task CHECK_pa_out;
        input [3:0] NEXT_pa_out;

        #0 begin
            if (NEXT_pa_out !== pa_out) begin
                $display("Error at time=%dns pa_out=%b, expected=%b", $time, pa_out, NEXT_pa_out);
                $fdisplay(TX_FILE, "Error at time=%dns pa_out=%b, expected=%b", $time, pa_out, NEXT_pa_out);
                $fflush(TX_FILE);
                TX_ERROR = TX_ERROR + 1;
            end
        end
    endtask

endmodule