////////////////////////////////////////////////////////////////////// //// //// //// eth_outputcontrol.v //// //// //// //// This file is part of the Ethernet IP core project //// //// http://www.opencores.org/projects/ethmac/ //// //// //// //// Author(s): //// //// - Igor Mohor (igorM@opencores.org) //// //// //// //// All additional information is avaliable in the Readme.txt //// //// file. //// //// //// ////////////////////////////////////////////////////////////////////// //// //// //// 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: eth_outputcontrol.v,v $ // Revision 1.1 2007-03-20 17:50:56 sithglan // add shit // // Revision 1.4 2002/07/09 20:11:59 mohor // Comment removed. // // Revision 1.3 2002/01/23 10:28:16 mohor // Link in the header changed. // // Revision 1.2 2001/10/19 08:43:51 mohor // eth_timescale.v changed to timescale.v This is done because of the // simulation of the few cores in a one joined project. // // Revision 1.1 2001/08/06 14:44:29 mohor // A define FPGA added to select between Artisan RAM (for ASIC) and Block Ram (For Virtex). // Include files fixed to contain no path. // File names and module names changed ta have a eth_ prologue in the name. // File eth_timescale.v is used to define timescale // All pin names on the top module are changed to contain _I, _O or _OE at the end. // Bidirectional signal MDIO is changed to three signals (Mdc_O, Mdi_I, Mdo_O // and Mdo_OE. The bidirectional signal must be created on the top level. This // is done due to the ASIC tools. // // Revision 1.1 2001/07/30 21:23:42 mohor // Directory structure changed. Files checked and joind together. // // Revision 1.3 2001/06/01 22:28:56 mohor // This files (MIIM) are fully working. They were thoroughly tested. The testbench is not updated. // // `include "timescale.v" module eth_outputcontrol(Clk, Reset, InProgress, ShiftedBit, BitCounter, WriteOp, NoPre, MdcEn_n, Mdo, MdoEn); parameter Tp = 1; input Clk; // Host Clock input Reset; // General Reset input WriteOp; // Write Operation Latch (When asserted, write operation is in progress) input NoPre; // No Preamble (no 32-bit preamble) input InProgress; // Operation in progress input ShiftedBit; // This bit is output of the shift register and is connected to the Mdo signal input [6:0] BitCounter; // Bit Counter input MdcEn_n; // MII Management Data Clock Enable signal is asserted for one Clk period before Mdc falls. output Mdo; // MII Management Data Output output MdoEn; // MII Management Data Output Enable wire SerialEn; reg MdoEn_2d; reg MdoEn_d; reg MdoEn; reg Mdo_2d; reg Mdo_d; reg Mdo; // MII Management Data Output // Generation of the Serial Enable signal (enables the serialization of the data) assign SerialEn = WriteOp & InProgress & ( BitCounter>31 | ( ( BitCounter == 0 ) & NoPre ) ) | ~WriteOp & InProgress & (( BitCounter>31 & BitCounter<46 ) | ( ( BitCounter == 0 ) & NoPre )); // Generation of the MdoEn signal always @ (posedge Clk or posedge Reset) begin if(Reset) begin MdoEn_2d <= #Tp 1'b0; MdoEn_d <= #Tp 1'b0; MdoEn <= #Tp 1'b0; end else begin if(MdcEn_n) begin MdoEn_2d <= #Tp SerialEn | InProgress & BitCounter<32; MdoEn_d <= #Tp MdoEn_2d; MdoEn <= #Tp MdoEn_d; end end end // Generation of the Mdo signal. always @ (posedge Clk or posedge Reset) begin if(Reset) begin Mdo_2d <= #Tp 1'b0; Mdo_d <= #Tp 1'b0; Mdo <= #Tp 1'b0; end else begin if(MdcEn_n) begin Mdo_2d <= #Tp ~SerialEn & BitCounter<32; Mdo_d <= #Tp ShiftedBit | Mdo_2d; Mdo <= #Tp Mdo_d; end end end endmodule