Committer:
svlach
Date:
Wed Dec 08 21:23:21 2010 +0000
Revision:
1:dcf2f8359398
Parent:
0:70c3bea805ee

        

Who changed what in which revision?

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svlach 0:70c3bea805ee 1 //---------------------------------------------------------------------------
svlach 0:70c3bea805ee 2 // Copyright (C) 2000 Dallas Semiconductor Corporation, All Rights Reserved.
svlach 0:70c3bea805ee 3 //
svlach 0:70c3bea805ee 4 // Permission is hereby granted, free of charge, to any person obtaining a
svlach 0:70c3bea805ee 5 // copy of this software and associated documentation files (the "Software"),
svlach 0:70c3bea805ee 6 // to deal in the Software without restriction, including without limitation
svlach 0:70c3bea805ee 7 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
svlach 0:70c3bea805ee 8 // and/or sell copies of the Software, and to permit persons to whom the
svlach 0:70c3bea805ee 9 // Software is furnished to do so, subject to the following conditions:
svlach 0:70c3bea805ee 10 //
svlach 0:70c3bea805ee 11 // The above copyright notice and this permission notice shall be included
svlach 0:70c3bea805ee 12 // in all copies or substantial portions of the Software.
svlach 0:70c3bea805ee 13 //
svlach 0:70c3bea805ee 14 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
svlach 0:70c3bea805ee 15 // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
svlach 0:70c3bea805ee 16 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
svlach 0:70c3bea805ee 17 // IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
svlach 0:70c3bea805ee 18 // OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
svlach 0:70c3bea805ee 19 // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
svlach 0:70c3bea805ee 20 // OTHER DEALINGS IN THE SOFTWARE.
svlach 0:70c3bea805ee 21 //
svlach 0:70c3bea805ee 22 // Except as contained in this notice, the name of Dallas Semiconductor
svlach 0:70c3bea805ee 23 // shall not be used except as stated in the Dallas Semiconductor
svlach 0:70c3bea805ee 24 // Branding Policy.
svlach 0:70c3bea805ee 25 //--------------------------------------------------------------------------
svlach 0:70c3bea805ee 26 //
svlach 0:70c3bea805ee 27 // crcutil.c - Keeps track of the CRC for 16 and 8 bit operations
svlach 0:70c3bea805ee 28 // version 2.00
svlach 0:70c3bea805ee 29
svlach 0:70c3bea805ee 30 // Include files
svlach 1:dcf2f8359398 31 #include "ownet.h"
svlach 0:70c3bea805ee 32
svlach 0:70c3bea805ee 33 // Local global variables
svlach 0:70c3bea805ee 34 unsigned short utilcrc16[MAX_PORTNUM];
svlach 0:70c3bea805ee 35 uchar utilcrc8[MAX_PORTNUM];
svlach 0:70c3bea805ee 36 static short oddparity[16] = { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 };
svlach 0:70c3bea805ee 37 static uchar dscrc_table[] = {
svlach 0:70c3bea805ee 38 0, 94,188,226, 97, 63,221,131,194,156,126, 32,163,253, 31, 65,
svlach 0:70c3bea805ee 39 157,195, 33,127,252,162, 64, 30, 95, 1,227,189, 62, 96,130,220,
svlach 0:70c3bea805ee 40 35,125,159,193, 66, 28,254,160,225,191, 93, 3,128,222, 60, 98,
svlach 0:70c3bea805ee 41 190,224, 2, 92,223,129, 99, 61,124, 34,192,158, 29, 67,161,255,
svlach 0:70c3bea805ee 42 70, 24,250,164, 39,121,155,197,132,218, 56,102,229,187, 89, 7,
svlach 0:70c3bea805ee 43 219,133,103, 57,186,228, 6, 88, 25, 71,165,251,120, 38,196,154,
svlach 0:70c3bea805ee 44 101, 59,217,135, 4, 90,184,230,167,249, 27, 69,198,152,122, 36,
svlach 0:70c3bea805ee 45 248,166, 68, 26,153,199, 37,123, 58,100,134,216, 91, 5,231,185,
svlach 0:70c3bea805ee 46 140,210, 48,110,237,179, 81, 15, 78, 16,242,172, 47,113,147,205,
svlach 0:70c3bea805ee 47 17, 79,173,243,112, 46,204,146,211,141,111, 49,178,236, 14, 80,
svlach 0:70c3bea805ee 48 175,241, 19, 77,206,144,114, 44,109, 51,209,143, 12, 82,176,238,
svlach 0:70c3bea805ee 49 50,108,142,208, 83, 13,239,177,240,174, 76, 18,145,207, 45,115,
svlach 0:70c3bea805ee 50 202,148,118, 40,171,245, 23, 73, 8, 86,180,234,105, 55,213,139,
svlach 0:70c3bea805ee 51 87, 9,235,181, 54,104,138,212,149,203, 41,119,244,170, 72, 22,
svlach 0:70c3bea805ee 52 233,183, 85, 11,136,214, 52,106, 43,117,151,201, 74, 20,246,168,
svlach 0:70c3bea805ee 53 116, 42,200,150, 21, 75,169,247,182,232, 10, 84,215,137,107, 53};
svlach 0:70c3bea805ee 54
svlach 0:70c3bea805ee 55 //--------------------------------------------------------------------------
svlach 0:70c3bea805ee 56 // Reset crc16 to the value passed in
svlach 0:70c3bea805ee 57 //
svlach 0:70c3bea805ee 58 // 'reset' - data to set crc16 to.
svlach 0:70c3bea805ee 59 //
svlach 0:70c3bea805ee 60 void setcrc16(int portnum, unsigned short reset)
svlach 0:70c3bea805ee 61 {
svlach 0:70c3bea805ee 62 utilcrc16[portnum&0x0FF] = reset;
svlach 0:70c3bea805ee 63 return;
svlach 0:70c3bea805ee 64 }
svlach 0:70c3bea805ee 65
svlach 0:70c3bea805ee 66 //--------------------------------------------------------------------------
svlach 0:70c3bea805ee 67 // Reset crc8 to the value passed in
svlach 0:70c3bea805ee 68 //
svlach 0:70c3bea805ee 69 // 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
svlach 0:70c3bea805ee 70 // indicate the symbolic port number.
svlach 0:70c3bea805ee 71 // 'reset' - data to set crc8 to
svlach 0:70c3bea805ee 72 //
svlach 0:70c3bea805ee 73 void setcrc8(int portnum, uchar reset)
svlach 0:70c3bea805ee 74 {
svlach 0:70c3bea805ee 75 utilcrc8[portnum&0x0FF] = reset;
svlach 0:70c3bea805ee 76 return;
svlach 0:70c3bea805ee 77 }
svlach 0:70c3bea805ee 78
svlach 0:70c3bea805ee 79 //--------------------------------------------------------------------------
svlach 0:70c3bea805ee 80 // Calculate a new CRC16 from the input data short. Return the current
svlach 0:70c3bea805ee 81 // CRC16 and also update the global variable CRC16.
svlach 0:70c3bea805ee 82 //
svlach 0:70c3bea805ee 83 // 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
svlach 0:70c3bea805ee 84 // indicate the symbolic port number.
svlach 0:70c3bea805ee 85 // 'data' - data to perform a CRC16 on
svlach 0:70c3bea805ee 86 //
svlach 0:70c3bea805ee 87 // Returns: the current CRC16
svlach 0:70c3bea805ee 88 //
svlach 0:70c3bea805ee 89 unsigned short docrc16(int portnum, unsigned short cdata)
svlach 0:70c3bea805ee 90 {
svlach 0:70c3bea805ee 91 cdata = (cdata ^ (utilcrc16[portnum&0x0FF] & 0xff)) & 0xff;
svlach 0:70c3bea805ee 92 utilcrc16[portnum&0x0FF] >>= 8;
svlach 0:70c3bea805ee 93
svlach 0:70c3bea805ee 94 if (oddparity[cdata & 0xf] ^ oddparity[cdata >> 4])
svlach 0:70c3bea805ee 95 utilcrc16[portnum&0x0FF] ^= 0xc001;
svlach 0:70c3bea805ee 96
svlach 0:70c3bea805ee 97 cdata <<= 6;
svlach 0:70c3bea805ee 98 utilcrc16[portnum&0x0FF] ^= cdata;
svlach 0:70c3bea805ee 99 cdata <<= 1;
svlach 0:70c3bea805ee 100 utilcrc16[portnum&0x0FF] ^= cdata;
svlach 0:70c3bea805ee 101
svlach 0:70c3bea805ee 102 return utilcrc16[portnum&0x0FF];
svlach 0:70c3bea805ee 103 }
svlach 0:70c3bea805ee 104
svlach 0:70c3bea805ee 105 //--------------------------------------------------------------------------
svlach 0:70c3bea805ee 106 // Update the Dallas Semiconductor One Wire CRC (utilcrc8) from the global
svlach 0:70c3bea805ee 107 // variable utilcrc8 and the argument.
svlach 0:70c3bea805ee 108 //
svlach 0:70c3bea805ee 109 // 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
svlach 0:70c3bea805ee 110 // indicate the symbolic port number.
svlach 0:70c3bea805ee 111 // 'x' - data byte to calculate the 8 bit crc from
svlach 0:70c3bea805ee 112 //
svlach 0:70c3bea805ee 113 // Returns: the updated utilcrc8.
svlach 0:70c3bea805ee 114 //
svlach 0:70c3bea805ee 115 uchar docrc8(int portnum, uchar x)
svlach 0:70c3bea805ee 116 {
svlach 0:70c3bea805ee 117 utilcrc8[portnum&0x0FF] = dscrc_table[utilcrc8[portnum&0x0FF] ^ x];
svlach 0:70c3bea805ee 118 return utilcrc8[portnum&0x0FF];
svlach 0:70c3bea805ee 119 }