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// File        : ../RTL/serialInterfaceEngine/usbTxWireArbiter.v

// Generated   : 11/10/06 05:37:24

// From        : ../RTL/serialInterfaceEngine/usbTxWireArbiter.asf

// By          : FSM2VHDL ver. 5.0.0.9

//////////////////////////////////////////////////////////////////////

////                                                              ////

//// usbTxWireArbiter

////                                                              ////

//// This file is part of the usbhostslave opencores effort.

//// http://www.opencores.org/cores/usbhostslave/                 ////

////                                                              ////

//// Module Description:                                          ////

//// 

////                                                              ////

//// To Do:                                                       ////

//// 

////                                                              ////

//// Author(s):                                                   ////

//// - Steve Fielding, sfielding@base2designs.com                 ////

////                                                              ////

//////////////////////////////////////////////////////////////////////

////                                                              ////

//// Copyright (C) 2004 Steve Fielding and OPENCORES.ORG          ////

////                                                              ////

//// 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                     ////

////                                                              ////

//////////////////////////////////////////////////////////////////////

//

`include "timescale.v"

`include "usbhostslave_constants_h.v"

`include "usbhostslave_serialinterfaceengine_h.v"

module USBTxWireArbiter (SIETxCtrl, SIETxData, SIETxFSRate, SIETxGnt, SIETxReq, SIETxWEn, TxBits, TxCtl, TxFSRate, USBWireRdyIn, USBWireRdyOut, USBWireWEn, clk, prcTxByteCtrl, prcTxByteData, prcTxByteFSRate, prcTxByteGnt, prcTxByteReq, prcTxByteWEn, rst);

input   SIETxCtrl;

input   [1:0] SIETxData;

input   SIETxFSRate;

input   SIETxReq;

input   SIETxWEn;

input   USBWireRdyIn;

input   clk;

input   prcTxByteCtrl;

input   [1:0] prcTxByteData;

input   prcTxByteFSRate;

input   prcTxByteReq;

input   prcTxByteWEn;

input   rst;

output  SIETxGnt;

output  [1:0] TxBits;

output  TxCtl;

output  TxFSRate;

output  USBWireRdyOut;

output  USBWireWEn;

output  prcTxByteGnt;

wire    SIETxCtrl;

wire    [1:0] SIETxData;

wire    SIETxFSRate;

reg     SIETxGnt, next_SIETxGnt;

wire    SIETxReq;

wire    SIETxWEn;

reg     [1:0] TxBits, next_TxBits;

reg     TxCtl, next_TxCtl;

reg     TxFSRate, next_TxFSRate;

wire    USBWireRdyIn;

reg     USBWireRdyOut, next_USBWireRdyOut;

reg     USBWireWEn, next_USBWireWEn;

wire    clk;

wire    prcTxByteCtrl;

wire    [1:0] prcTxByteData;

wire    prcTxByteFSRate;

reg     prcTxByteGnt, next_prcTxByteGnt;

wire    prcTxByteReq;

wire    prcTxByteWEn;

wire    rst;

// diagram signals declarations

reg  muxSIENotPTXB, next_muxSIENotPTXB;

// BINARY ENCODED state machine: txWireArb

// State codes definitions:

`define START_TARB 2'b00

`define TARB_WAIT_REQ 2'b01

`define PTXB_ACT 2'b10

`define SIE_TX_ACT 2'b11

reg [1:0] CurrState_txWireArb;

reg [1:0] NextState_txWireArb;

// Diagram actions (continuous assignments allowed only: assign ...)

// processTxByte/SIETransmitter mux

always @(USBWireRdyIn)

begin

    USBWireRdyOut <= USBWireRdyIn;

end

always @(muxSIENotPTXB or SIETxWEn or SIETxData or

SIETxCtrl or prcTxByteWEn or prcTxByteData or prcTxByteCtrl or

SIETxFSRate or prcTxByteFSRate)

begin

    if (muxSIENotPTXB  == 1'b1)

    begin

        USBWireWEn <= SIETxWEn;

        TxBits <= SIETxData;

        TxCtl <= SIETxCtrl;

        TxFSRate <= SIETxFSRate;

    end

    else

    begin

        USBWireWEn <= prcTxByteWEn;

        TxBits <= prcTxByteData;

        TxCtl <= prcTxByteCtrl;

        TxFSRate <= prcTxByteFSRate;

    end

end

//--------------------------------------------------------------------

// Machine: txWireArb

//--------------------------------------------------------------------

//----------------------------------

// Next State Logic (combinatorial)

//----------------------------------

always @ (prcTxByteReq or SIETxReq or prcTxByteGnt or muxSIENotPTXB or SIETxGnt or CurrState_txWireArb)

begin : txWireArb_NextState

  NextState_txWireArb <= CurrState_txWireArb;

  // Set default values for outputs and signals

  next_prcTxByteGnt <= prcTxByteGnt;

  next_muxSIENotPTXB <= muxSIENotPTXB;

  next_SIETxGnt <= SIETxGnt;

  case (CurrState_txWireArb)

    `START_TARB:

      NextState_txWireArb <= `TARB_WAIT_REQ;

    `TARB_WAIT_REQ:

      if (prcTxByteReq == 1'b1)

      begin

        NextState_txWireArb <= `PTXB_ACT;

        next_prcTxByteGnt <= 1'b1;

        next_muxSIENotPTXB <= 1'b0;

      end

      else if (SIETxReq == 1'b1)

      begin

        NextState_txWireArb <= `SIE_TX_ACT;

        next_SIETxGnt <= 1'b1;

        next_muxSIENotPTXB <= 1'b1;

      end

    `PTXB_ACT:

      if (prcTxByteReq == 1'b0)

      begin

        NextState_txWireArb <= `TARB_WAIT_REQ;

        next_prcTxByteGnt <= 1'b0;

      end

    `SIE_TX_ACT:

      if (SIETxReq == 1'b0)

      begin

        NextState_txWireArb <= `TARB_WAIT_REQ;

        next_SIETxGnt <= 1'b0;

      end

  endcase

end

//----------------------------------

// Current State Logic (sequential)

//----------------------------------

always @ (posedge clk)

begin : txWireArb_CurrentState

  if (rst)

    CurrState_txWireArb <= `START_TARB;

  else

    CurrState_txWireArb <= NextState_txWireArb;

end

//----------------------------------

// Registered outputs logic

//----------------------------------

always @ (posedge clk)

begin : txWireArb_RegOutput

  if (rst)

  begin

    muxSIENotPTXB <= 1'b0;

    prcTxByteGnt <= 1'b0;

    SIETxGnt <= 1'b0;

  end

  else

  begin

    muxSIENotPTXB <= next_muxSIENotPTXB;

    prcTxByteGnt <= next_prcTxByteGnt;

    SIETxGnt <= next_SIETxGnt;

  end

end

endmodule