OpenFPGA/openfpga_flow/benchmarks/iwls2005/usb_funct/rtl/usbf_crc16.v

116 lines
5.3 KiB
Verilog

/////////////////////////////////////////////////////////////////////
//// ////
//// USB CRC5 and CRC16 Modules ////
//// ////
//// ////
//// Author: Rudolf Usselmann ////
//// rudi@asics.ws ////
//// ////
//// ////
//// Downloaded from: http://www.opencores.org/cores/usb/ ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000-2003 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: usbf_crc16.v,v 1.2 2003/10/17 02:36:57 rudi Exp $
//
// $Date: 2003/10/17 02:36:57 $
// $Revision: 1.2 $
// $Author: rudi $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: usbf_crc16.v,v $
// Revision 1.2 2003/10/17 02:36:57 rudi
// - Disabling bit stuffing and NRZI encoding during speed negotiation
// - Now the core can send zero size packets
// - Fixed register addresses for some of the higher endpoints
// (conversion between decimal/hex was wrong)
// - The core now does properly evaluate the function address to
// determine if the packet was intended for it.
// - Various other minor bugs and typos
//
// Revision 1.1 2001/08/03 05:30:09 rudi
//
//
// 1) Reorganized directory structure
//
// Revision 1.0 2001/03/07 09:17:12 rudi
//
//
// Changed all revisions to revision 1.0. This is because OpenCores CVS
// interface could not handle the original '0.1' revision ....
//
// Revision 0.1.0.1 2001/02/28 08:10:42 rudi
// Initial Release
//
//
`include "usbf_defines.v"
///////////////////////////////////////////////////////////////////
//
// CRC16
//
///////////////////////////////////////////////////////////////////
module usbf_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