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// ////////////////////////////////////////////////////////////////////
// // ////
// // MAC_tx_addr_add.v ////
// // ////
// // This file is part of the Ethernet IP core project ////
// // http://www.opencores.org/projects.cgi/wr_en/ethernet_tri_mode/////
// // ////
// // Author(s): ////
// // - Jon Gao (gaojon@yahoo.com) ////
// // ////
// // ////
// ////////////////////////////////////////////////////////////////////
// // ////
// // Copyright (C) 2001 Authors ////
// // ////
// // 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: MAC_tx_addr_add.v,v $
// Revision 1.3 2006/01/19 14:07:54 maverickist
// verification is complete.
//
// Revision 1.2 2005/12/16 06:44:18 Administrator
// replaced tab with space.
// passed 9.6k length frame test.
//
// Revision 1.1.1.1 2005/12/13 01:51:45 Administrator
// no message
//
module MAC_tx_addr_add
(Reset ,
Clk ,
MAC_tx_addr_init ,
MAC_tx_addr_rd ,
MAC_tx_addr_data ,
//CPU ,
MAC_add_prom_data ,
MAC_add_prom_add ,
MAC_add_prom_wr
);
input Reset ;
input Clk ;
input MAC_tx_addr_rd ;
input MAC_tx_addr_init ;
output [7:0] MAC_tx_addr_data ;
//CPU ;
input [7:0] MAC_add_prom_data ;
input [2:0] MAC_add_prom_add ;
input MAC_add_prom_wr ;
// ******************************************************************************
// internal signals
// ******************************************************************************
reg [2:0] add_rd;
wire [2:0] add_wr;
wire [7:0] din;
//wire [7:0] dout;
reg [7:0] dout;
wire wr_en;
reg MAC_add_prom_wr_dl1;
reg MAC_add_prom_wr_dl2;
// ******************************************************************************
// write data from cpu to prom
// ******************************************************************************
always @ (posedge Clk or posedge Reset)
if (Reset)
begin
MAC_add_prom_wr_dl1 <=0;
MAC_add_prom_wr_dl2 <=0;
end
else
begin
MAC_add_prom_wr_dl1 <=MAC_add_prom_wr;
MAC_add_prom_wr_dl2 <=MAC_add_prom_wr_dl1;
end
assign wr_en =MAC_add_prom_wr_dl1&!MAC_add_prom_wr_dl2;
assign add_wr =MAC_add_prom_add;
assign din =MAC_add_prom_data;
// ******************************************************************************
// read data from cpu to prom
// ******************************************************************************
always @ (posedge Clk or posedge Reset)
if (Reset)
add_rd <=0;
else if (MAC_tx_addr_init)
add_rd <=0;
else if (MAC_tx_addr_rd)
add_rd <=add_rd + 1;
assign MAC_tx_addr_data=dout;
// ******************************************************************************
// b port for read ,a port for write .
// ******************************************************************************
reg [7:0] address_ram [0:7];
always @(posedge Clk)
if(wr_en)
address_ram[add_wr] <= din;
always @(posedge Clk)
dout <= address_ram[add_rd];
endmodule // MAC_tx_addr_add
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