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

////                                                              ////

////  File name: pci_in_reg.v                                     ////

////                                                              ////

////  This file is part of the "PCI bridge" project               ////

////  http://www.opencores.org/cores/pci/                         ////

////                                                              ////

////  Author(s):                                                  ////

////      - Tadej Markovic, tadej@opencores.org                   ////

////                                                              ////

////  All additional information is avaliable in the README.txt   ////

////  file.                                                       ////

////                                                              ////

////                                                              ////

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

////                                                              ////

//// Copyright (C) 2000 Tadej Markovic, tadej@opencores.org       ////

////                                                              ////

//// This source file may be used and distributed without         ////

//// restriction provided that this copyright statement is not    ////

//// removed from the file and that any derivative work contains  ////

//// the original copyright notice and the associated disclaimer. ////

////                                                              ////

//// This source file 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 2.1 of the License, or (at your option) any   ////

//// later version.                                               ////

////                                                              ////

//// This source 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 source; if not, download it   ////

//// from http://www.opencores.org/lgpl.shtml                     ////

////                                                              ////

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

//

// CVS Revision History

//

// $Log: not supported by cvs2svn $

//

`include "constants.v"

// Module is used for registering PCI input signals 

// It provides data flip flops with reset

module PCI_IN_REG

(

    reset_in,

    clk_in,

    pci_gnt_in,

    pci_frame_in,

    pci_irdy_in,

    pci_trdy_in,

    pci_stop_in,

    pci_devsel_in,

    pci_idsel_in,

    pci_ad_in,

    pci_cbe_in,

    pci_gnt_reg_out,

    pci_frame_reg_out,

    pci_irdy_reg_out,

    pci_trdy_reg_out,

    pci_stop_reg_out,

    pci_devsel_reg_out,

    pci_idsel_reg_out,

    pci_ad_reg_out,

    pci_cbe_reg_out

);

input                   reset_in, clk_in ;

input           pci_gnt_in ;

input           pci_frame_in ;

input           pci_irdy_in ;

input           pci_trdy_in ;

input           pci_stop_in ;

input           pci_devsel_in ;

input                   pci_idsel_in ;

input [31:0]    pci_ad_in ;

input [3:0]     pci_cbe_in ;

output          pci_gnt_reg_out ;

output          pci_frame_reg_out ;

output          pci_irdy_reg_out ;

output          pci_trdy_reg_out ;

output          pci_stop_reg_out ;

output          pci_devsel_reg_out ;

output                  pci_idsel_reg_out ;

output [31:0]   pci_ad_reg_out ;

output [3:0]    pci_cbe_reg_out ;

reg             pci_gnt_reg_out ;

reg             pci_frame_reg_out ;

reg             pci_irdy_reg_out ;

reg             pci_trdy_reg_out ;

reg             pci_stop_reg_out ;

reg             pci_devsel_reg_out ;

reg                             pci_idsel_reg_out ;

reg    [31:0]   pci_ad_reg_out ;

reg    [3:0]    pci_cbe_reg_out ;

always@(posedge reset_in or posedge clk_in)

begin

    if ( reset_in )

    begin

                pci_gnt_reg_out         <= #`FF_DELAY 1'b1 ;

                pci_frame_reg_out       <= #`FF_DELAY 1'b1 ;

                pci_irdy_reg_out        <= #`FF_DELAY 1'b1 ;

                pci_trdy_reg_out        <= #`FF_DELAY 1'b1 ;

                pci_stop_reg_out        <= #`FF_DELAY 1'b1 ;

                pci_devsel_reg_out      <= #`FF_DELAY 1'b1 ;

                pci_idsel_reg_out       <= #`FF_DELAY 1'b0 ; // active high!

    end

    else

        begin

                pci_gnt_reg_out         <= #`FF_DELAY pci_gnt_in ;

                pci_frame_reg_out       <= #`FF_DELAY pci_frame_in ;

                pci_irdy_reg_out        <= #`FF_DELAY pci_irdy_in ;

                pci_trdy_reg_out        <= #`FF_DELAY pci_trdy_in ;

                pci_stop_reg_out        <= #`FF_DELAY pci_stop_in ;

                pci_devsel_reg_out      <= #`FF_DELAY pci_devsel_in ;

                pci_idsel_reg_out       <= #`FF_DELAY pci_idsel_in ;

        end

end

always@(posedge reset_in or posedge clk_in)

begin

    if ( reset_in )

        pci_ad_reg_out <= #`FF_DELAY 32'h0000_0000 ;

    else

        pci_ad_reg_out <= #`FF_DELAY pci_ad_in ;

end

always@(posedge reset_in or posedge clk_in)

begin

    if ( reset_in )

        pci_cbe_reg_out <= #`FF_DELAY 4'h0 ;

    else

        pci_cbe_reg_out <= #`FF_DELAY pci_cbe_in ;

end

endmodule