Subversion Repositories usb2uart

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

////                                                             ////

////  USB CRC16 Modules                                          ////

////                                                             ////

////                                                             ////

////  Author: Rudolf Usselmann                                   ////

////          rudi@asics.ws                                      ////

////                                                             ////

////                                                             ////

////  Downloaded from: http://www.opencores.org/cores/usb1_funct/////

////                                                             ////

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

////                                                             ////

//// Copyright (C) 2000-2002 Rudolf Usselmann                    ////

////                         www.asics.ws                        ////

////                         rudi@asics.ws                       ////

////                                                             ////

//// 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 SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////

//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////

//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////

//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////

//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////

//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////

//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////

//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////

//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////

//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////

//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////

//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////

//// POSSIBILITY OF SUCH DAMAGE.                                 ////

////                                                             ////

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

//  CVS Log

//

//  $Id: usb1_crc16.v,v 1.1.1.1 2002-09-19 12:07:39 rudi Exp $

//

//  $Date: 2002-09-19 12:07:39 $

//  $Revision: 1.1.1.1 $

//  $Author: rudi $

//  $Locker:  $

//  $State: Exp $

//

// Change History:

//               $Log: not supported by cvs2svn $

//

//

//

//

//

//

//                            

`include "usb1_defines.v"

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

//

// CRC16

//

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

module usb1_crc16(crc_in, din, crc_out);

input   [15:0]   crc_in;

input   [7:0]    din;

output  [15:0]   crc_out;

assign crc_out[0] =      din[7] ^ din[6] ^ din[5] ^ din[4] ^ din[3] ^

                        din[2] ^ din[1] ^ din[0] ^ crc_in[8] ^ crc_in[9] ^

                        crc_in[10] ^ crc_in[11] ^ crc_in[12] ^ crc_in[13] ^

                        crc_in[14] ^ crc_in[15];

assign crc_out[1] =     din[7] ^ din[6] ^ din[5] ^ din[4] ^ din[3] ^ din[2] ^

                        din[1] ^ crc_in[9] ^ crc_in[10] ^ crc_in[11] ^

                        crc_in[12] ^ crc_in[13] ^ crc_in[14] ^ crc_in[15];

assign crc_out[2] =     din[1] ^ din[0] ^ crc_in[8] ^ crc_in[9];

assign crc_out[3] =     din[2] ^ din[1] ^ crc_in[9] ^ crc_in[10];

assign crc_out[4] =     din[3] ^ din[2] ^ crc_in[10] ^ crc_in[11];

assign crc_out[5] =     din[4] ^ din[3] ^ crc_in[11] ^ crc_in[12];

assign crc_out[6] =     din[5] ^ din[4] ^ crc_in[12] ^ crc_in[13];

assign crc_out[7] =     din[6] ^ din[5] ^ crc_in[13] ^ crc_in[14];

assign crc_out[8] =     din[7] ^ din[6] ^ crc_in[0] ^ crc_in[14] ^ crc_in[15];

assign crc_out[9] =     din[7] ^ crc_in[1] ^ crc_in[15];

assign crc_out[10] =    crc_in[2];

assign crc_out[11] =    crc_in[3];

assign crc_out[12] =    crc_in[4];

assign crc_out[13] =    crc_in[5];

assign crc_out[14] =    crc_in[6];

assign crc_out[15] =    din[7] ^ din[6] ^ din[5] ^ din[4] ^ din[3] ^ din[2] ^

                        din[1] ^ din[0] ^ crc_in[7] ^ crc_in[8] ^ crc_in[9] ^

                        crc_in[10] ^ crc_in[11] ^ crc_in[12] ^ crc_in[13] ^

                        crc_in[14] ^ crc_in[15];

endmodule