// Copyright 2009 Altera Corporation. All rights reserved. // Altera products are protected under numerous U.S. and foreign patents, // maskwork rights, copyrights and other intellectual property laws. // // This reference design file, and your use thereof, is subject to and governed // by the terms and conditions of the applicable Altera Reference Design // License Agreement (either as signed by you or found at www.altera.com). By // using this reference design file, you indicate your acceptance of such terms // and conditions between you and Altera Corporation. In the event that you do // not agree with such terms and conditions, you may not use the reference // design file and please promptly destroy any copies you have made. // // This reference design file is being provided on an "as-is" basis and as an // accommodation and therefore all warranties, representations or guarantees of // any kind (whether express, implied or statutory) including, without // limitation, warranties of merchantability, non-infringement, or fitness for // a particular purpose, are specifically disclaimed. By making this reference // design file available, Altera expressly does not recommend, suggest or // require that this reference design file be used in combination with any // other product not provided by Altera. ///////////////////////////////////////////////////////////////////////////// // // 32 bit CRC of 4 data bits (forward - LSB first) // polynomial : 00a00805 // x^23 + x^21 + x^11 + x^2 + x^0 // // CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC DDDD // 00000000001111111111222222222233 0000 // 01234567890123456789012345678901 0123 // C00 = ............................#... .... // C01 = .............................#.. .... // C02 = ............................#.#. .... // C03 = .............................#.# .... // C04 = #.............................#. .... // C05 = .#.............................# .... // C06 = ..#............................. .... // C07 = ...#............................ .... // C08 = ....#........................... .... // C09 = .....#.......................... .... // C10 = ......#......................... .... // C11 = .......#....................#... .... // C12 = ........#....................#.. .... // C13 = .........#....................#. .... // C14 = ..........#....................# .... // C15 = ...........#.................... .... // C16 = ............#................... .... // C17 = .............#.................. .... // C18 = ..............#................. .... // C19 = ...............#................ .... // C20 = ................#............... .... // C21 = .................#..........#... .... // C22 = ..................#..........#.. .... // C23 = ...................#........#.#. .... // C24 = ....................#........#.# .... // C25 = .....................#........#. .... // C26 = ......................#........# .... // C27 = .......................#........ .... // C28 = ........................#....... .... // C29 = .........................#...... .... // C30 = ..........................#..... .... // C31 = ...........................#.... .... // // Number of XORs used is 32 // Maximum XOR input count is 3 // Best possible depth in 4 LUTs = 1 // Best possible depth in 5 LUTs = 1 // Best possible depth in 6 LUTs = 1 // Total XOR inputs 48 // module fec_rot_4 ( input [31:0] c, output [31:0] co ); assign co[0] = c[28]; assign co[1] = c[29]; assign co[2] = c[28] ^ c[30]; assign co[3] = c[29] ^ c[31]; assign co[4] = c[0] ^ c[30]; assign co[5] = c[1] ^ c[31]; assign co[6] = c[2]; assign co[7] = c[3]; assign co[8] = c[4]; assign co[9] = c[5]; assign co[10] = c[6]; assign co[11] = c[7] ^ c[28]; assign co[12] = c[8] ^ c[29]; assign co[13] = c[9] ^ c[30]; assign co[14] = c[10] ^ c[31]; assign co[15] = c[11]; assign co[16] = c[12]; assign co[17] = c[13]; assign co[18] = c[14]; assign co[19] = c[15]; assign co[20] = c[16]; assign co[21] = c[17] ^ c[28]; assign co[22] = c[18] ^ c[29]; assign co[23] = c[19] ^ c[28] ^ c[30]; assign co[24] = c[20] ^ c[29] ^ c[31]; assign co[25] = c[21] ^ c[30]; assign co[26] = c[22] ^ c[31]; assign co[27] = c[23]; assign co[28] = c[24]; assign co[29] = c[25]; assign co[30] = c[26]; assign co[31] = c[27]; endmodule