--- /dev/null
+//---------------------------------------------------------------------------
+// Copyright (C) 2000 Dallas Semiconductor Corporation, All Rights Reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+// IN NO EVENT SHALL DALLAS SEMICONDUCTOR BE LIABLE FOR ANY CLAIM, DAMAGES
+// OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+// OTHER DEALINGS IN THE SOFTWARE.
+//
+// Except as contained in this notice, the name of Dallas Semiconductor
+// shall not be used except as stated in the Dallas Semiconductor
+// Branding Policy.
+//--------------------------------------------------------------------------
+//
+// crcutil.c - Keeps track of the CRC for 16 and 8 bit operations
+// version 2.00
+
+// Include files
+#include "ownet.h"
+
+// Local global variables
+ushort utilcrc16[MAX_PORTNUM];
+uchar utilcrc8[MAX_PORTNUM];
+static short oddparity[16] = { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 };
+static uchar dscrc_table[] = {
+ 0, 94,188,226, 97, 63,221,131,194,156,126, 32,163,253, 31, 65,
+ 157,195, 33,127,252,162, 64, 30, 95, 1,227,189, 62, 96,130,220,
+ 35,125,159,193, 66, 28,254,160,225,191, 93, 3,128,222, 60, 98,
+ 190,224, 2, 92,223,129, 99, 61,124, 34,192,158, 29, 67,161,255,
+ 70, 24,250,164, 39,121,155,197,132,218, 56,102,229,187, 89, 7,
+ 219,133,103, 57,186,228, 6, 88, 25, 71,165,251,120, 38,196,154,
+ 101, 59,217,135, 4, 90,184,230,167,249, 27, 69,198,152,122, 36,
+ 248,166, 68, 26,153,199, 37,123, 58,100,134,216, 91, 5,231,185,
+ 140,210, 48,110,237,179, 81, 15, 78, 16,242,172, 47,113,147,205,
+ 17, 79,173,243,112, 46,204,146,211,141,111, 49,178,236, 14, 80,
+ 175,241, 19, 77,206,144,114, 44,109, 51,209,143, 12, 82,176,238,
+ 50,108,142,208, 83, 13,239,177,240,174, 76, 18,145,207, 45,115,
+ 202,148,118, 40,171,245, 23, 73, 8, 86,180,234,105, 55,213,139,
+ 87, 9,235,181, 54,104,138,212,149,203, 41,119,244,170, 72, 22,
+ 233,183, 85, 11,136,214, 52,106, 43,117,151,201, 74, 20,246,168,
+ 116, 42,200,150, 21, 75,169,247,182,232, 10, 84,215,137,107, 53};
+
+//--------------------------------------------------------------------------
+// Reset crc16 to the value passed in
+//
+// 'reset' - data to set crc16 to.
+//
+void setcrc16(int portnum, ushort reset)
+{
+ utilcrc16[portnum&0x0FF] = reset;
+ return;
+}
+
+//--------------------------------------------------------------------------
+// Reset crc8 to the value passed in
+//
+// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
+// indicate the symbolic port number.
+// 'reset' - data to set crc8 to
+//
+void setcrc8(int portnum, uchar reset)
+{
+ utilcrc8[portnum&0x0FF] = reset;
+ return;
+}
+
+//--------------------------------------------------------------------------
+// Calculate a new CRC16 from the input data short. Return the current
+// CRC16 and also update the global variable CRC16.
+//
+// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
+// indicate the symbolic port number.
+// 'data' - data to perform a CRC16 on
+//
+// Returns: the current CRC16
+//
+ushort docrc16(int portnum, ushort cdata)
+{
+ cdata = (cdata ^ (utilcrc16[portnum&0x0FF] & 0xff)) & 0xff;
+ utilcrc16[portnum&0x0FF] >>= 8;
+
+ if (oddparity[cdata & 0xf] ^ oddparity[cdata >> 4])
+ utilcrc16[portnum&0x0FF] ^= 0xc001;
+
+ cdata <<= 6;
+ utilcrc16[portnum&0x0FF] ^= cdata;
+ cdata <<= 1;
+ utilcrc16[portnum&0x0FF] ^= cdata;
+
+ return utilcrc16[portnum&0x0FF];
+}
+
+//--------------------------------------------------------------------------
+// Update the Dallas Semiconductor One Wire CRC (utilcrc8) from the global
+// variable utilcrc8 and the argument.
+//
+// 'portnum' - number 0 to MAX_PORTNUM-1. This number is provided to
+// indicate the symbolic port number.
+// 'x' - data byte to calculate the 8 bit crc from
+//
+// Returns: the updated utilcrc8.
+//
+uchar docrc8(int portnum, uchar x)
+{
+ utilcrc8[portnum&0x0FF] = dscrc_table[utilcrc8[portnum&0x0FF] ^ x];
+ return utilcrc8[portnum&0x0FF];
+}
tm3d / owSlave2.git / blobdiff