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

////                                                              ////

//// dpMem_dc.v                                                 ////

////                                                              ////

//// This file is part of the usbhostslave opencores effort.

//// <http://www.opencores.org/cores//>                           ////

////                                                              ////

//// Module Description:                                          ////

//// Synchronous dual port memory with dual clocks

////                                                              ////

//// To Do:                                                       ////

//// 

////                                                              ////

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

//// - Steve Fielding, sfielding@base2designs.com                 ////

////                                                              ////

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

////                                                              ////

//// Copyright (C) 2004 Steve Fielding and 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>                   ////

////                                                              ////

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

//

`include "timescale.v"

module dpMem_dc(  addrIn, addrOut, wrClk, rdClk, dataIn, writeEn, readEn, dataOut);

   //FIFO_DEPTH = ADDR_WIDTH^2

   parameter FIFO_WIDTH = 8;

   parameter FIFO_DEPTH = 64;

   parameter ADDR_WIDTH = 6;

   input wrClk;

   input rdClk;

   input [FIFO_WIDTH-1:0] dataIn;

   output [FIFO_WIDTH-1:0] dataOut;

   input                   writeEn;

   input                   readEn;

   input [ADDR_WIDTH-1:0]  addrIn;

   input [ADDR_WIDTH-1:0]  addrOut;

   wire                    wrClk;

   wire                    rdClk;

   wire [FIFO_WIDTH-1:0]   dataIn;

   //reg [FIFO_WIDTH-1:0] dataOut;

   wire [FIFO_WIDTH-1:0]   dataOut;

   wire                    writeEn;

   wire                    readEn;

   wire [ADDR_WIDTH-1:0]   addrIn;

   wire [ADDR_WIDTH-1:0]   addrOut;

   // Added no_rw_check on this -- Julius

   reg [FIFO_WIDTH-1:0]    buffer [0:FIFO_DEPTH-1] /*synthesis syn_ramstyle = "no_rw_check"*/;

   // Modifying this to ensure this is inferred as a block RAM

   // Register address

   reg [ADDR_WIDTH-1:0]    addrOut_r;

   always @(posedge rdClk)

     //not sure if we should have this enable here:

     // if (readEn)

     addrOut_r <= addrOut;

   assign dataOut = buffer[addrOut_r];

   // synchronous write

   always @(posedge wrClk) begin

      if (writeEn == 1'b1)

        buffer[addrIn] <= dataIn;

   end

/*

   // synchronous read. Introduces one clock cycle delay

   always @(posedge rdClk) begin

      dataOut <= buffer[addrOut];

   end

   // synchronous write

   always @(posedge wrClk) begin

      if (writeEn == 1'b1)

        buffer[addrIn] <= dataIn;

   end

*/

endmodule