| ///////////////////////////////////////////////////////////////////// |
| //// //// |
| //// 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 "usb1d_defines.v" |
| |
| /////////////////////////////////////////////////////////////////// |
| // |
| // CRC16 |
| // |
| /////////////////////////////////////////////////////////////////// |
| |
| module usb1d_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 |
| |
