//////////////////////////////////////////////////////////////////////
//// ////
//// eth_rxcounters.v ////
//// ////
//// This file is part of the Ethernet IP core project ////
//// http://www.opencores.org/cores/ethmac/ ////
//// ////
//// Author(s): ////
//// - Igor Mohor (igorM@opencores.org) ////
//// - Novan Hartadi (novan@vlsi.itb.ac.id) ////
//// - Mahmud Galela (mgalela@vlsi.itb.ac.id) ////
//// ////
//// 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_rxcounters.v,v $
// 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 1.1 2001/06/27 21:26:19 mohor
// Initial release of the RxEthMAC module.
//
//
//
//
//
//
`include "timescale.v"
module eth_rxcounters (MRxClk, Reset, MRxDV, StateIdle, StateSFD, StateData, StateDrop, StatePreamble,
MRxDEqD, DlyCrcEn, DlyCrcCnt, Transmitting, MaxFL, r_IFG, HugEn, IFGCounterEq24,
ByteCntEq0, ByteCntEq1, ByteCntEq6, ByteCntGreat2, ByteCntSmall7, ByteCntMaxFrame,
ByteCnt
);
parameter Tp = 1;
input MRxClk;
input Reset;
input MRxDV;
input StateSFD;
input [1:0] StateData;
input MRxDEqD;
input StateIdle;
input StateDrop;
input DlyCrcEn;
input StatePreamble;
input Transmitting;
input HugEn;
input [15:0] MaxFL;
input r_IFG;
output IFGCounterEq24; // IFG counter reaches 9600 ns (960 ns)
output [3:0] DlyCrcCnt; // Delayed CRC counter
output ByteCntEq0; // Byte counter = 0
output ByteCntEq1; // Byte counter = 1
output ByteCntEq6; // Byte counter = 6
output ByteCntGreat2; // Byte counter > 2
output ByteCntSmall7; // Byte counter < 7
output ByteCntMaxFrame; // Byte counter = MaxFL
output [15:0] ByteCnt; // Byte counter
wire ResetByteCounter;
wire IncrementByteCounter;
wire ResetIFGCounter;
wire IncrementIFGCounter;
wire ByteCntMax;
reg [15:0] ByteCnt;
reg [3:0] DlyCrcCnt;
reg [4:0] IFGCounter;
assign ResetByteCounter = MRxDV & (StateSFD & MRxDEqD | StateData[0] & ByteCntMaxFrame);
assign IncrementByteCounter = ~ResetByteCounter & MRxDV &
(StatePreamble | StateSFD | StateIdle & ~Transmitting |
StateData[1] & ~ByteCntMax & ~(DlyCrcEn & |DlyCrcCnt)
);
always @ (posedge MRxClk or posedge Reset)
begin
if(Reset)
ByteCnt[15:0] else
begin
if(ResetByteCounter)
ByteCnt[15:0] else
if(IncrementByteCounter)
ByteCnt[15:0] end
end
assign ByteCntEq0 = ByteCnt == 16'h0;
assign ByteCntEq1 = ByteCnt == 16'h1;
assign ByteCntEq6 = ByteCnt == 16'h6;
assign ByteCntGreat2 = ByteCnt > 16'h2;
assign ByteCntSmall7 = ByteCnt < 16'h7;
assign ByteCntMax = ByteCnt == 16'hffff;
assign ByteCntMaxFrame = ByteCnt == MaxFL[15:0] & ~HugEn;
assign ResetIFGCounter = StateSFD & MRxDV & MRxDEqD | StateDrop;
assign IncrementIFGCounter = ~ResetIFGCounter & (StateDrop | StateIdle | StatePreamble | StateSFD) & ~IFGCounterEq24;
always @ (posedge MRxClk or posedge Reset)
begin
if(Reset)
IFGCounter[4:0] else
begin
if(ResetIFGCounter)
IFGCounter[4:0] else
if(IncrementIFGCounter)
IFGCounter[4:0] end
end
assign IFGCounterEq24 = (IFGCounter[4:0] == 5'h18) | r_IFG; // 24*400 = 9600 ns or r_IFG is set to 1
always @ (posedge MRxClk or posedge Reset)
begin
if(Reset)
DlyCrcCnt[3:0] else
begin
if(DlyCrcCnt[3:0] == 4'h9)
DlyCrcCnt[3:0] else
if(DlyCrcEn & StateSFD)
DlyCrcCnt[3:0] else
if(DlyCrcEn & (|DlyCrcCnt[3:0]))
DlyCrcCnt[3:0] end
end
endmodule
