source: XOpenSparcT1/trunk/Xilinx/ddr2_phy_dm_iob.v @ 10

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//*****************************************************************************
//   ____  ____
//  /   /\/   /
// /___/  \  /    Vendor: Xilinx
// \   \   \/     Version: 3.6
//  \   \         Application: MIG
//  /   /         Filename: ddr2_phy_dm_iob.v
// /___/   /\     Date Last Modified: $Date: 2010/06/29 12:03:43 $
// \   \  /  \    Date Created: Wed Aug 16 2006
//  \___\/\___\
//
//Device: Virtex-5
//Design Name: DDR2
//Purpose:
//   This module places the data mask signals into the IOBs.
//Reference:
//Revision History:
//   Rev 1.1 - To fix timing issues with Synplicity 9.6.1, syn_preserve 
//             attribute added for the instance u_dm_ce. PK. 11/11/08
//*****************************************************************************

`timescale 1ns/1ps

module ddr2_phy_dm_iob
  (
   input  clk90,
   input  dm_ce,
   input  mask_data_rise,
   input  mask_data_fall,
   output ddr_dm
   );

  wire    dm_out;
  wire    dm_ce_r;

  FDRSE_1 u_dm_ce
    (
     .Q    (dm_ce_r),
     .C    (clk90),
     .CE   (1'b1),
     .D    (dm_ce),
     .R   (1'b0),
     .S   (1'b0)
     ) /* synthesis syn_preserve=1 */;

  ODDR #
    (
     .SRTYPE("SYNC"),
     .DDR_CLK_EDGE("SAME_EDGE")
     )
    u_oddr_dm
      (
       .Q  (dm_out),
       .C  (clk90),
       .CE (dm_ce_r),
       .D1 (mask_data_rise),
       .D2 (mask_data_fall),
       .R  (1'b0),
       .S  (1'b0)
       );

  OBUF u_obuf_dm
    (
     .I (dm_out),
     .O (ddr_dm)
     );

endmodule