-//---------------------------------------------------------------------------\r
-// Copyright (C) 2000 Dallas Semiconductor Corporation, All Rights Reserved.\r
-//\r
-// Permission is hereby granted, free of charge, to any person obtaining a\r
-// copy of this software and associated documentation files (the "Software"),\r
-// to deal in the Software without restriction, including without limitation\r
-// the rights to use, copy, modify, merge, publish, distribute, sublicense,\r
-// and/or sell copies of the Software, and to permit persons to whom the\r
-// Software is furnished to do so, subject to the following conditions:\r
-//\r
-// The above copyright notice and this permission notice shall be included\r
-// in all copies or substantial portions of the Software.\r
-//\r
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS\r
-// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF\r
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.\r
-// IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES\r
-// OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,\r
-// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR\r
-// OTHER DEALINGS IN THE SOFTWARE.\r
-//\r
-// Except as contained in this notice, the name of Dallas Semiconductor\r
-// shall not be used except as stated in the Dallas Semiconductor\r
-// Branding Policy.\r
-//--------------------------------------------------------------------------\r
-//\r
-// crcutil.c - Keeps track of the CRC for 16 and 8 bit operations\r
-// version 2.00\r
-\r
-// Include files\r
-#include "ownet.h"\r
-\r
-// Local global variables\r
-ushort utilcrc16[MAX_PORTNUM];\r
-uchar utilcrc8[MAX_PORTNUM];\r
-static short oddparity[16] = { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 };\r
-static uchar dscrc_table[] = {\r
- 0, 94,188,226, 97, 63,221,131,194,156,126, 32,163,253, 31, 65,\r
- 157,195, 33,127,252,162, 64, 30, 95, 1,227,189, 62, 96,130,220,\r
- 35,125,159,193, 66, 28,254,160,225,191, 93, 3,128,222, 60, 98,\r
- 190,224, 2, 92,223,129, 99, 61,124, 34,192,158, 29, 67,161,255,\r
- 70, 24,250,164, 39,121,155,197,132,218, 56,102,229,187, 89, 7,\r
- 219,133,103, 57,186,228, 6, 88, 25, 71,165,251,120, 38,196,154,\r
- 101, 59,217,135, 4, 90,184,230,167,249, 27, 69,198,152,122, 36,\r
- 248,166, 68, 26,153,199, 37,123, 58,100,134,216, 91, 5,231,185,\r
- 140,210, 48,110,237,179, 81, 15, 78, 16,242,172, 47,113,147,205,\r
- 17, 79,173,243,112, 46,204,146,211,141,111, 49,178,236, 14, 80,\r
- 175,241, 19, 77,206,144,114, 44,109, 51,209,143, 12, 82,176,238,\r
- 50,108,142,208, 83, 13,239,177,240,174, 76, 18,145,207, 45,115,\r
- 202,148,118, 40,171,245, 23, 73, 8, 86,180,234,105, 55,213,139,\r
- 87, 9,235,181, 54,104,138,212,149,203, 41,119,244,170, 72, 22,\r
- 233,183, 85, 11,136,214, 52,106, 43,117,151,201, 74, 20,246,168,\r
- 116, 42,200,150, 21, 75,169,247,182,232, 10, 84,215,137,107, 53};\r
-\r
-//--------------------------------------------------------------------------\r
-// Reset crc16 to the value passed in\r
-//\r
-// 'reset' - data to set crc16 to.\r
-//\r
-void setcrc16(int portnum, ushort reset)\r
-{\r
- utilcrc16[portnum&0x0FF] = reset;\r
- return;\r
-}\r
-\r
-//--------------------------------------------------------------------------\r
-// Reset crc8 to the value passed in\r
-//\r
-// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to\r
-// indicate the symbolic port number.\r
-// 'reset' - data to set crc8 to\r
-//\r
-void setcrc8(int portnum, uchar reset)\r
-{\r
- utilcrc8[portnum&0x0FF] = reset;\r
- return;\r
-}\r
-\r
-//--------------------------------------------------------------------------\r
-// Calculate a new CRC16 from the input data short. Return the current\r
-// CRC16 and also update the global variable CRC16.\r
-//\r
-// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to\r
-// indicate the symbolic port number.\r
-// 'data' - data to perform a CRC16 on\r
-//\r
-// Returns: the current CRC16\r
-//\r
-ushort docrc16(int portnum, ushort cdata)\r
-{\r
- cdata = (cdata ^ (utilcrc16[portnum&0x0FF] & 0xff)) & 0xff;\r
- utilcrc16[portnum&0x0FF] >>= 8;\r
-\r
- if (oddparity[cdata & 0xf] ^ oddparity[cdata >> 4])\r
- utilcrc16[portnum&0x0FF] ^= 0xc001;\r
-\r
- cdata <<= 6;\r
- utilcrc16[portnum&0x0FF] ^= cdata;\r
- cdata <<= 1;\r
- utilcrc16[portnum&0x0FF] ^= cdata;\r
-\r
- return utilcrc16[portnum&0x0FF];\r
-}\r
-\r
-//--------------------------------------------------------------------------\r
-// Update the Dallas Semiconductor One Wire CRC (utilcrc8) from the global\r
-// variable utilcrc8 and the argument.\r
-//\r
-// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to\r
-// indicate the symbolic port number.\r
-// 'x' - data byte to calculate the 8 bit crc from\r
-//\r
-// Returns: the updated utilcrc8.\r
-//\r
-uchar docrc8(int portnum, uchar x)\r
-{\r
- utilcrc8[portnum&0x0FF] = dscrc_table[utilcrc8[portnum&0x0FF] ^ x];\r
- return utilcrc8[portnum&0x0FF];\r
-}\r