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

////                                                              ////

////  ps2_io_ctrl.v                                               ////

////                                                              ////

////  This file is part of the "ps2" project                      ////

////  http://www.opencores.org/cores/ps2/                         ////

////                                                              ////

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

////      - mihad@opencores.org                                   ////

////      - Miha Dolenc                                           ////

////                                                              ////

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

////  file.                                                       ////

////                                                              ////

////                                                              ////

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

////                                                              ////

//// Copyright (C) 2000 Miha Dolenc, mihad@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 $

//

// synopsys translate_off

`include "timescale.v"

// synopsys translate_on

module ps2_io_ctrl

(

    clk_i,

    rst_i,

    ps2_ctrl_kbd_clk_en_i_,

    ps2_ctrl_kbd_data_en_i_,

    ps2_kbd_clk_pad_i,

    ps2_kbd_clk_pad_oe_o,

    ps2_kbd_data_pad_oe_o,

    inhibit_kbd_if_i,

    ps2_ctrl_kbd_clk_o

);

input clk_i,

      rst_i,

      ps2_ctrl_kbd_clk_en_i_,

      ps2_ctrl_kbd_data_en_i_,

      ps2_kbd_clk_pad_i,

      inhibit_kbd_if_i ;

output ps2_kbd_clk_pad_oe_o,

       ps2_kbd_data_pad_oe_o,

       ps2_ctrl_kbd_clk_o ;

reg    ps2_kbd_clk_pad_oe_o,

       ps2_kbd_data_pad_oe_o ;

always@(posedge clk_i or posedge rst_i)

begin

    if ( rst_i )

    begin

        ps2_kbd_clk_pad_oe_o  <= #1 1'b0 ;

        ps2_kbd_data_pad_oe_o <= #1 1'b0 ;

    end

    else

    begin

        ps2_kbd_clk_pad_oe_o  <= #1 !ps2_ctrl_kbd_clk_en_i_ || inhibit_kbd_if_i ;

        ps2_kbd_data_pad_oe_o <= #1 !ps2_ctrl_kbd_data_en_i_ ;

    end

end

reg inhibit_kbd_if_previous ;

always@(posedge clk_i or posedge rst_i)

begin

    if ( rst_i )

        inhibit_kbd_if_previous <= #1 1'b1 ;

    else

        inhibit_kbd_if_previous <= #1 inhibit_kbd_if_i ;

end

assign ps2_ctrl_kbd_clk_o = ps2_kbd_clk_pad_i || ps2_kbd_clk_pad_oe_o && inhibit_kbd_if_previous ;

endmodule // ps2_io_ctrl