X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/raggedstone/blobdiff_plain/528d015aa19100f9f97b3469ab7d2aafa43b425e..40a1f26c3a09dbd1f71f4fd7f3aca74f387a09db:/ethernet/source/ethernet/eth_shiftreg.v diff --git a/ethernet/source/ethernet/eth_shiftreg.v b/ethernet/source/ethernet/eth_shiftreg.v new file mode 100644 index 0000000..167513b --- /dev/null +++ b/ethernet/source/ethernet/eth_shiftreg.v @@ -0,0 +1,157 @@ +////////////////////////////////////////////////////////////////////// +//// //// +//// eth_shiftreg.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_shiftreg.v,v $ +// Revision 1.1 2007-03-20 17:50:56 sithglan +// add shit +// +// Revision 1.6 2005/03/08 14:45:09 igorm +// Case statement improved for synthesys. +// +// Revision 1.5 2002/08/14 18:16:59 mohor +// LinkFail signal was not latching appropriate bit. +// +// Revision 1.4 2002/03/02 21:06:01 mohor +// LinkFail signal was not latching appropriate bit. +// +// 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_shiftreg(Clk, Reset, MdcEn_n, Mdi, Fiad, Rgad, CtrlData, WriteOp, ByteSelect, + LatchByte, ShiftedBit, Prsd, LinkFail); + + +parameter Tp=1; + +input Clk; // Input clock (Host clock) +input Reset; // Reset signal +input MdcEn_n; // Enable signal is asserted for one Clk period before Mdc falls. +input Mdi; // MII input data +input [4:0] Fiad; // PHY address +input [4:0] Rgad; // Register address (within the selected PHY) +input [15:0]CtrlData; // Control data (data to be written to the PHY) +input WriteOp; // The current operation is a PHY register write operation +input [3:0] ByteSelect; // Byte select +input [1:0] LatchByte; // Byte select for latching (read operation) + +output ShiftedBit; // Bit shifted out of the shift register +output[15:0]Prsd; // Read Status Data (data read from the PHY) +output LinkFail; // Link Integrity Signal + +reg [7:0] ShiftReg; // Shift register for shifting the data in and out +reg [15:0]Prsd; +reg LinkFail; + + + + +// ShiftReg[7:0] :: Shift Register Data +always @ (posedge Clk or posedge Reset) +begin + if(Reset) + begin + ShiftReg[7:0] <= #Tp 8'h0; + Prsd[15:0] <= #Tp 16'h0; + LinkFail <= #Tp 1'b0; + end + else + begin + if(MdcEn_n) + begin + if(|ByteSelect) + begin + case (ByteSelect[3:0]) // synopsys parallel_case full_case + 4'h1 : ShiftReg[7:0] <= #Tp {2'b01, ~WriteOp, WriteOp, Fiad[4:1]}; + 4'h2 : ShiftReg[7:0] <= #Tp {Fiad[0], Rgad[4:0], 2'b10}; + 4'h4 : ShiftReg[7:0] <= #Tp CtrlData[15:8]; + 4'h8 : ShiftReg[7:0] <= #Tp CtrlData[7:0]; + endcase + end + else + begin + ShiftReg[7:0] <= #Tp {ShiftReg[6:0], Mdi}; + if(LatchByte[0]) + begin + Prsd[7:0] <= #Tp {ShiftReg[6:0], Mdi}; + if(Rgad == 5'h01) + LinkFail <= #Tp ~ShiftReg[1]; // this is bit [2], because it is not shifted yet + end + else + begin + if(LatchByte[1]) + Prsd[15:8] <= #Tp {ShiftReg[6:0], Mdi}; + end + end + end + end +end + + +assign ShiftedBit = ShiftReg[7]; + + +endmodule