Subversion Repositories cpu8080

////////////////////////////////////////////////////////////////////////////////

// Copyright (c) 1995-2003 Xilinx, Inc.

// All Right Reserved.

////////////////////////////////////////////////////////////////////////////////

//   ____  ____

//  /   /\/   /

// /___/  \  /    Vendor: Xilinx

// \   \   \/     Version : 8.2.02i

//  \   \         Application : ISE

//  /   /         Filename : cpu8080_tbw.tfw

// /___/   /\     Timestamp : Sat Nov 18 13:39:13 2006

// \   \  /  \

//  \___\/\___\

//

//Command:

//Design Name: cpu8080_tbw

//Device: Xilinx

//

`timescale 1ns/1ps

module cpu8080_tbw;

    wire [15:0] addr;

    reg [7:0] data$inout$reg = 8'b00000000;

    wire [7:0] data = data$inout$reg;

    wire readmem;

    wire writemem;

    wire readio;

    wire writeio;

    wire intr;

    wire inta;

    wire waitr;

    wire [2:0] r;

    wire [2:0] g;

    wire [2:0] b;

    wire hsync_n;

    wire vsync_n;

    reg ps2_clk = 1'b0;

    reg ps2_data = 1'b0;

    reg reset_n = 1'b0;

    reg clock = 1'b0;

    wire [7:0] diag;

    parameter PERIOD = 40;

    parameter real DUTY_CYCLE = 0.5;

    parameter OFFSET = 100;

    initial    // Clock process for clock

    begin

        #OFFSET;

        forever

        begin

            clock = 1'b0;

            #(PERIOD-(PERIOD*DUTY_CYCLE)) clock = 1'b1;

            #(PERIOD*DUTY_CYCLE);

        end

    end

    testbench UUT (

        .addr(addr),

        .data(data),

        .readmem(readmem),

        .writemem(writemem),

        .readio(readio),

        .writeio(writeio),

        .intr(intr),

        .inta(inta),

        .waitr(waitr),

        .r(r),

        .g(g),

        .b(b),

        .hsync_n(hsync_n),

        .vsync_n(vsync_n),

        .ps2_clk(ps2_clk),

        .ps2_data(ps2_data),

        .reset_n(reset_n),

        .clock(clock),

        .diag(diag));

    integer TX_FILE = 0;

    integer TX_ERROR = 0;

    initial begin  // Open the results file...

        TX_FILE = $fopen("results.txt");

        #200040 // Final time:  200040 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

        // -------------  Current Time:  110ns

        #110;

        ps2_clk = 1'b1;

        ps2_data = 1'b1;

        reset_n = 1'b0;

        data$inout$reg = 8'bZZZZZZZZ;

        // -------------------------------------

        // -------------  Current Time:  130ns

        #20;

        CHECK_intr(1'b0);

        CHECK_diag(8'bXXX11X00);

        // -------------------------------------

        // -------------  Current Time:  270ns

        #140;

        reset_n = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  370ns

        #100;

        CHECK_b(3'bXXX);

        CHECK_g(3'bXXX);

        CHECK_r(3'bXXX);

        // -------------------------------------

        // -------------  Current Time:  390ns

        #20;

        ps2_data = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  410ns

        #20;

        CHECK_diag(8'bXXX01X00);

        // -------------------------------------

        // -------------  Current Time:  510ns

        #100;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  530ns

        #20;

        CHECK_diag(8'bXXX00X00);

        // -------------------------------------

        // -------------  Current Time:  590ns

        #60;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  650ns

        #60;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  670ns

        #20;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  690ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  830ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  850ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  990ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  1010ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  1150ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  1170ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  1310ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  1330ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  1470ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  1490ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  1630ns

        #140;

        ps2_clk = 1'b1;

        ps2_data = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  1650ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  1790ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  1810ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  1950ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  1970ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  1990ns

        #20;

        ps2_data = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  2010ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  2110ns

        #100;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  2130ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  2270ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  2290ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  2430ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  2450ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  2590ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  2610ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  2750ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  2770ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  2910ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  2930ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  3070ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  3090ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  3230ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  3250ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  3310ns

        #60;

        ps2_data = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  3330ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  3390ns

        #60;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  3410ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  3550ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  3570ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  3590ns

        #20;

        ps2_data = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  3610ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  3710ns

        #100;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  3730ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  3870ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  3890ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  5910ns

        #2020;

        ps2_data = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  5930ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  6070ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  6090ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  6230ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  6250ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  6390ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  6410ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  6550ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  6570ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  6630ns

        #60;

        ps2_data = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  6650ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  6710ns

        #60;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  6730ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  6870ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  6890ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  6910ns

        #20;

        ps2_data = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  6930ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  7030ns

        #100;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  7050ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  7190ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  7210ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  7350ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  7370ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  7510ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  7530ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  7550ns

        #20;

        ps2_data = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  7570ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  7670ns

        #100;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  7690ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  7830ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  7850ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  7910ns

        #60;

        ps2_data = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  7930ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  7990ns

        #60;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  8010ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  8150ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  8170ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  8310ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  8330ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  8470ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  8490ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  8630ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  8650ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  8790ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  8810ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  8950ns

        #140;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  8970ns

        #20;

        CHECK_diag(8'bXXX00X01);

        // -------------------------------------

        // -------------  Current Time:  9110ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  9130ns

        #20;

        CHECK_diag(8'bXXX01X01);

        // -------------------------------------

        // -------------  Current Time:  9190ns

        #60;

        ps2_data = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  9210ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  9270ns

        #60;

        ps2_clk = 1'b0;

        // -------------------------------------

        // -------------  Current Time:  9290ns

        #20;

        CHECK_diag(8'bXXX10X01);

        // -------------------------------------

        // -------------  Current Time:  9430ns

        #140;

        ps2_clk = 1'b1;

        // -------------------------------------

        // -------------  Current Time:  9450ns

        #20;

        CHECK_diag(8'bXXX11X01);

        // -------------------------------------

        // -------------  Current Time:  31090ns

        #21640;

        CHECK_b(3'b000);

        CHECK_g(3'b000);

        CHECK_r(3'b000);

        // -------------------------------------

        // -------------  Current Time:  31890ns

        #800;

        CHECK_hsync_n(1'b0);

        // -------------------------------------

        // -------------  Current Time:  39890ns

        #8000;

        CHECK_hsync_n(1'b1);

        // -------------------------------------

        // -------------  Current Time:  43890ns

        #4000;

        CHECK_b(3'bXXX);

        CHECK_g(3'bXXX);

        CHECK_r(3'bXXX);

        // -------------------------------------

        // -------------  Current Time:  95090ns

        #51200;

        CHECK_b(3'b000);

        CHECK_g(3'b000);

        CHECK_r(3'b000);

        // -------------------------------------

        // -------------  Current Time:  95890ns

        #800;

        CHECK_hsync_n(1'b0);

        // -------------------------------------

        // -------------  Current Time:  103890ns

        #8000;

        CHECK_hsync_n(1'b1);

        // -------------------------------------

        // -------------  Current Time:  107890ns

        #4000;

        CHECK_b(3'bXXX);

        CHECK_g(3'bXXX);

        CHECK_r(3'bXXX);

        // -------------------------------------

        // -------------  Current Time:  159090ns

        #51200;

        CHECK_b(3'b000);

        CHECK_g(3'b000);

        CHECK_r(3'b000);

        // -------------------------------------

        // -------------  Current Time:  159890ns

        #800;

        CHECK_hsync_n(1'b0);

        // -------------------------------------

        // -------------  Current Time:  167890ns

        #8000;

        CHECK_hsync_n(1'b1);

        // -------------------------------------

        // -------------  Current Time:  171890ns

        #4000;

        CHECK_b(3'bXXX);

        CHECK_g(3'bXXX);

        CHECK_r(3'bXXX);

        // -------------------------------------

    end

    task CHECK_addr;

        input [15:0] NEXT_addr;

        #0 begin

            if (NEXT_addr !== addr) begin

                $display("Error at time=%dns addr=%b, expected=%b", $time, addr, NEXT_addr);

                $fdisplay(TX_FILE, "Error at time=%dns addr=%b, expected=%b", $time, addr, NEXT_addr);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_readmem;

        input NEXT_readmem;

        #0 begin

            if (NEXT_readmem !== readmem) begin

                $display("Error at time=%dns readmem=%b, expected=%b", $time, readmem, NEXT_readmem);

                $fdisplay(TX_FILE, "Error at time=%dns readmem=%b, expected=%b", $time, readmem, NEXT_readmem);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_writemem;

        input NEXT_writemem;

        #0 begin

            if (NEXT_writemem !== writemem) begin

                $display("Error at time=%dns writemem=%b, expected=%b", $time, writemem, NEXT_writemem);

                $fdisplay(TX_FILE, "Error at time=%dns writemem=%b, expected=%b", $time, writemem, NEXT_writemem);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_readio;

        input NEXT_readio;

        #0 begin

            if (NEXT_readio !== readio) begin

                $display("Error at time=%dns readio=%b, expected=%b", $time, readio, NEXT_readio);

                $fdisplay(TX_FILE, "Error at time=%dns readio=%b, expected=%b", $time, readio, NEXT_readio);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_writeio;

        input NEXT_writeio;

        #0 begin

            if (NEXT_writeio !== writeio) begin

                $display("Error at time=%dns writeio=%b, expected=%b", $time, writeio, NEXT_writeio);

                $fdisplay(TX_FILE, "Error at time=%dns writeio=%b, expected=%b", $time, writeio, NEXT_writeio);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_intr;

        input NEXT_intr;

        #0 begin

            if (NEXT_intr !== intr) begin

                $display("Error at time=%dns intr=%b, expected=%b", $time, intr, NEXT_intr);

                $fdisplay(TX_FILE, "Error at time=%dns intr=%b, expected=%b", $time, intr, NEXT_intr);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_inta;

        input NEXT_inta;

        #0 begin

            if (NEXT_inta !== inta) begin

                $display("Error at time=%dns inta=%b, expected=%b", $time, inta, NEXT_inta);

                $fdisplay(TX_FILE, "Error at time=%dns inta=%b, expected=%b", $time, inta, NEXT_inta);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_waitr;

        input NEXT_waitr;

        #0 begin

            if (NEXT_waitr !== waitr) begin

                $display("Error at time=%dns waitr=%b, expected=%b", $time, waitr, NEXT_waitr);

                $fdisplay(TX_FILE, "Error at time=%dns waitr=%b, expected=%b", $time, waitr, NEXT_waitr);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_r;

        input [2:0] NEXT_r;

        #0 begin

            if (NEXT_r !== r) begin

                $display("Error at time=%dns r=%b, expected=%b", $time, r, NEXT_r);

                $fdisplay(TX_FILE, "Error at time=%dns r=%b, expected=%b", $time, r, NEXT_r);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_g;

        input [2:0] NEXT_g;

        #0 begin

            if (NEXT_g !== g) begin

                $display("Error at time=%dns g=%b, expected=%b", $time, g, NEXT_g);

                $fdisplay(TX_FILE, "Error at time=%dns g=%b, expected=%b", $time, g, NEXT_g);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_b;

        input [2:0] NEXT_b;

        #0 begin

            if (NEXT_b !== b) begin

                $display("Error at time=%dns b=%b, expected=%b", $time, b, NEXT_b);

                $fdisplay(TX_FILE, "Error at time=%dns b=%b, expected=%b", $time, b, NEXT_b);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_hsync_n;

        input NEXT_hsync_n;

        #0 begin

            if (NEXT_hsync_n !== hsync_n) begin

                $display("Error at time=%dns hsync_n=%b, expected=%b", $time, hsync_n, NEXT_hsync_n);

                $fdisplay(TX_FILE, "Error at time=%dns hsync_n=%b, expected=%b", $time, hsync_n, NEXT_hsync_n);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_vsync_n;

        input NEXT_vsync_n;

        #0 begin

            if (NEXT_vsync_n !== vsync_n) begin

                $display("Error at time=%dns vsync_n=%b, expected=%b", $time, vsync_n, NEXT_vsync_n);

                $fdisplay(TX_FILE, "Error at time=%dns vsync_n=%b, expected=%b", $time, vsync_n, NEXT_vsync_n);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

    task CHECK_diag;

        input [7:0] NEXT_diag;

        #0 begin

            if (NEXT_diag !== diag) begin

                $display("Error at time=%dns diag=%b, expected=%b", $time, diag, NEXT_diag);

                $fdisplay(TX_FILE, "Error at time=%dns diag=%b, expected=%b", $time, diag, NEXT_diag);

                $fflush(TX_FILE);

                TX_ERROR = TX_ERROR + 1;

            end

        end

    endtask

endmodule