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// synthesis translate_off
`timescale 1ns / 1ps
// synthesis translate_on

// turn off superfluous verilog processor warnings 
// altera message_level Level1 
// altera message_off 10034 10035 10036 10037 10230 10240 10030 

module led_pio (
                 // inputs:
                  address,
                  chipselect,
                  clk,
                  reset_n,
                  write_n,
                  writedata,

                 // outputs:
                  out_port,
                  readdata
               )
;

  output  [  1: 0] out_port;
  output  [  1: 0] readdata;
  input   [  1: 0] address;
  input            chipselect;
  input            clk;
  input            reset_n;
  input            write_n;
  input   [  1: 0] writedata;

  wire             clk_en;
  reg     [  1: 0] data_out;
  wire    [  1: 0] out_port;
  wire    [  1: 0] read_mux_out;
  wire    [  1: 0] readdata;
  assign clk_en = 1;
  //s1, which is an e_avalon_slave
  assign read_mux_out = {2 {(address == 0)}} & data_out;
  always @(posedge clk or negedge reset_n)
    begin
      if (reset_n == 0)
          data_out <= 0;
      else if (chipselect && ~write_n && (address == 0))
          data_out <= writedata[1 : 0];
    end


  assign readdata = read_mux_out;
  assign out_port = data_out;

endmodule

