Mike Fruge / OneWire

Implementation of 1-Wire with added Alarm Search Functionality

Dependents:   Max32630_One_Wire_Interface

OneWire_Masters/OneWireMaster.cpp@36:b6b5985a5e40, 2016-04-04 (annotated)

Committer:
IanBenzMaxim
Date:
Mon Apr 04 13:46:06 2016 +0000
Revision:
36:b6b5985a5e40
Parent:
32:bce180b544ed
Child:
42:698635a0d073
Corrected missed naming replacement.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
j3 5:ce108eeb878d 1 /******************************************************************//**
j3 5:ce108eeb878d 2 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
j3 5:ce108eeb878d 3 *
j3 5:ce108eeb878d 4 * Permission is hereby granted, free of charge, to any person obtaining a
j3 5:ce108eeb878d 5 * copy of this software and associated documentation files (the "Software"),
j3 5:ce108eeb878d 6 * to deal in the Software without restriction, including without limitation
j3 5:ce108eeb878d 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
j3 5:ce108eeb878d 8 * and/or sell copies of the Software, and to permit persons to whom the
j3 5:ce108eeb878d 9 * Software is furnished to do so, subject to the following conditions:
j3 5:ce108eeb878d 10 *
j3 5:ce108eeb878d 11 * The above copyright notice and this permission notice shall be included
j3 5:ce108eeb878d 12 * in all copies or substantial portions of the Software.
j3 5:ce108eeb878d 13 *
j3 5:ce108eeb878d 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
j3 5:ce108eeb878d 15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
j3 5:ce108eeb878d 16 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
j3 5:ce108eeb878d 17 * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
j3 5:ce108eeb878d 18 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
j3 5:ce108eeb878d 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
j3 5:ce108eeb878d 20 * OTHER DEALINGS IN THE SOFTWARE.
j3 5:ce108eeb878d 21 *
j3 5:ce108eeb878d 22 * Except as contained in this notice, the name of Maxim Integrated
j3 5:ce108eeb878d 23 * Products, Inc. shall not be used except as stated in the Maxim Integrated
j3 5:ce108eeb878d 24 * Products, Inc. Branding Policy.
j3 5:ce108eeb878d 25 *
j3 5:ce108eeb878d 26 * The mere transfer of this software does not imply any licenses
j3 5:ce108eeb878d 27 * of trade secrets, proprietary technology, copyrights, patents,
j3 5:ce108eeb878d 28 * trademarks, maskwork rights, or any other form of intellectual
j3 5:ce108eeb878d 29 * property whatsoever. Maxim Integrated Products, Inc. retains all
j3 5:ce108eeb878d 30 * ownership rights.
j3 5:ce108eeb878d 31 **********************************************************************/
j3 5:ce108eeb878d 32
j3 5:ce108eeb878d 33
j3 15:f6cb0d906fb6 34 #include "OneWireMaster.h"
IanBenzMaxim 27:d5aaefa252f1 35 #include "RomId.hpp"
IanBenzMaxim 27:d5aaefa252f1 36
IanBenzMaxim 27:d5aaefa252f1 37
IanBenzMaxim 27:d5aaefa252f1 38 using namespace std;
j3 15:f6cb0d906fb6 39
j3 15:f6cb0d906fb6 40
j3 17:b646b1e3970b 41 const uint16_t OneWireMaster::_oddparity[] = { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 };
j3 15:f6cb0d906fb6 42
j3 15:f6cb0d906fb6 43
IanBenzMaxim 32:bce180b544ed 44 OneWireMaster::CmdResult OneWireMaster::OWFirst(SearchState & searchState)
j3 15:f6cb0d906fb6 45 {
j3 17:b646b1e3970b 46 // reset the search state
IanBenzMaxim 32:bce180b544ed 47 searchState.reset();
j3 17:b646b1e3970b 48
IanBenzMaxim 32:bce180b544ed 49 return OWSearch(searchState);
j3 15:f6cb0d906fb6 50 }
j3 15:f6cb0d906fb6 51
j3 15:f6cb0d906fb6 52
j3 15:f6cb0d906fb6 53 //*********************************************************************
IanBenzMaxim 32:bce180b544ed 54 OneWireMaster::CmdResult OneWireMaster::OWNext(SearchState & searchState)
j3 15:f6cb0d906fb6 55 {
j3 17:b646b1e3970b 56 // leave the search state alone
IanBenzMaxim 32:bce180b544ed 57 return OWSearch(searchState);
j3 15:f6cb0d906fb6 58 }
j3 15:f6cb0d906fb6 59
j3 15:f6cb0d906fb6 60
j3 15:f6cb0d906fb6 61 //*********************************************************************
j3 23:e8e403d61359 62 OneWireMaster::CmdResult OneWireMaster::OWVerify(const RomId & romId)
j3 15:f6cb0d906fb6 63 {
j3 23:e8e403d61359 64 OneWireMaster::CmdResult result;
IanBenzMaxim 32:bce180b544ed 65 SearchState searchState;
j3 15:f6cb0d906fb6 66
j3 15:f6cb0d906fb6 67 // set search to find the same device
IanBenzMaxim 32:bce180b544ed 68 searchState.last_discrepancy = 64;
IanBenzMaxim 32:bce180b544ed 69 searchState.last_device_flag = false;
j3 15:f6cb0d906fb6 70
IanBenzMaxim 32:bce180b544ed 71 result = OWSearch(searchState);
j3 23:e8e403d61359 72 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 73 {
j3 15:f6cb0d906fb6 74 // check if same device found
IanBenzMaxim 32:bce180b544ed 75 if (romId != searchState.romId)
j3 15:f6cb0d906fb6 76 {
j3 23:e8e403d61359 77 result = OneWireMaster::OperationFailure;
j3 15:f6cb0d906fb6 78 }
j3 15:f6cb0d906fb6 79 }
j3 15:f6cb0d906fb6 80
j3 17:b646b1e3970b 81 return result;
j3 15:f6cb0d906fb6 82 }
j3 15:f6cb0d906fb6 83
j3 15:f6cb0d906fb6 84
j3 15:f6cb0d906fb6 85 //*********************************************************************
IanBenzMaxim 32:bce180b544ed 86 void OneWireMaster::OWTargetSetup(SearchState & searchState)
j3 15:f6cb0d906fb6 87 {
j3 15:f6cb0d906fb6 88 // set the search state to find SearchFamily type devices
IanBenzMaxim 32:bce180b544ed 89 std::uint8_t familyCode = searchState.romId.familyCode();
IanBenzMaxim 32:bce180b544ed 90 searchState.reset();
IanBenzMaxim 32:bce180b544ed 91 searchState.romId.setFamilyCode(familyCode);
IanBenzMaxim 32:bce180b544ed 92 searchState.last_discrepancy = 64;
j3 15:f6cb0d906fb6 93 }
j3 5:ce108eeb878d 94
j3 5:ce108eeb878d 95
j3 5:ce108eeb878d 96 //*********************************************************************
IanBenzMaxim 32:bce180b544ed 97 void OneWireMaster::OWFamilySkipSetup(SearchState & searchState)
j3 15:f6cb0d906fb6 98 {
j3 15:f6cb0d906fb6 99 // set the Last discrepancy to last family discrepancy
IanBenzMaxim 32:bce180b544ed 100 searchState.last_discrepancy = searchState.last_family_discrepancy;
j3 17:b646b1e3970b 101
j3 15:f6cb0d906fb6 102 // clear the last family discrpepancy
IanBenzMaxim 32:bce180b544ed 103 searchState.last_family_discrepancy = 0;
j3 17:b646b1e3970b 104
j3 15:f6cb0d906fb6 105 // check for end of list
IanBenzMaxim 32:bce180b544ed 106 if (searchState.last_discrepancy == 0)
j3 15:f6cb0d906fb6 107 {
IanBenzMaxim 32:bce180b544ed 108 searchState.last_device_flag = true;
j3 15:f6cb0d906fb6 109 }
j3 15:f6cb0d906fb6 110 }
j3 15:f6cb0d906fb6 111
j3 15:f6cb0d906fb6 112
j3 15:f6cb0d906fb6 113 //*********************************************************************
j3 23:e8e403d61359 114 OneWireMaster::CmdResult OneWireMaster::OWReadROM(RomId & romId)
j3 15:f6cb0d906fb6 115 {
j3 23:e8e403d61359 116 OneWireMaster::CmdResult result;
j3 17:b646b1e3970b 117 uint8_t buf[2 + RomId::byteLen];
j3 17:b646b1e3970b 118
j3 17:b646b1e3970b 119 result = OWReset();
j3 23:e8e403d61359 120 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 121 {
IanBenzMaxim 24:8942d8478d68 122 result = OWWriteByte(READ_ROM);
j3 17:b646b1e3970b 123 }
j3 17:b646b1e3970b 124
j3 17:b646b1e3970b 125 // read the ROM
j3 23:e8e403d61359 126 if (result == OneWireMaster::Success)
j3 17:b646b1e3970b 127 {
j3 17:b646b1e3970b 128 result = OWReadBlock(buf, RomId::byteLen);
j3 15:f6cb0d906fb6 129 }
j3 15:f6cb0d906fb6 130
j3 17:b646b1e3970b 131 // verify CRC8
IanBenzMaxim 24:8942d8478d68 132 if ((result == OneWireMaster::Success) && (RomId::calculateCRC8(buf, RomId::byteLen) == 0))
j3 17:b646b1e3970b 133 {
j3 17:b646b1e3970b 134 romId = RomId(reinterpret_cast<std::uint8_t (&)[RomId::byteLen]>(buf[0]));
j3 17:b646b1e3970b 135 }
j3 17:b646b1e3970b 136
j3 17:b646b1e3970b 137 return result;
j3 15:f6cb0d906fb6 138 }
j3 15:f6cb0d906fb6 139
j3 15:f6cb0d906fb6 140
j3 15:f6cb0d906fb6 141 //*********************************************************************
j3 23:e8e403d61359 142 OneWireMaster::CmdResult OneWireMaster::OWSkipROM(void)
j3 15:f6cb0d906fb6 143 {
j3 23:e8e403d61359 144 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 145
j3 17:b646b1e3970b 146 result = OWReset();
j3 23:e8e403d61359 147 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 148 {
IanBenzMaxim 24:8942d8478d68 149 result = OWWriteByte(SKIP_ROM);
j3 15:f6cb0d906fb6 150 }
j3 15:f6cb0d906fb6 151
j3 17:b646b1e3970b 152 return result;
j3 15:f6cb0d906fb6 153 }
j3 15:f6cb0d906fb6 154
j3 15:f6cb0d906fb6 155
j3 15:f6cb0d906fb6 156 //*********************************************************************
j3 23:e8e403d61359 157 OneWireMaster::CmdResult OneWireMaster::OWMatchROM(const RomId & romId)
j3 15:f6cb0d906fb6 158 {
j3 23:e8e403d61359 159 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 160
j3 17:b646b1e3970b 161 uint8_t buf[1 + RomId::byteLen];
j3 17:b646b1e3970b 162
j3 17:b646b1e3970b 163 // use MatchROM
j3 17:b646b1e3970b 164 result = OWReset();
j3 23:e8e403d61359 165 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 166 {
IanBenzMaxim 24:8942d8478d68 167 buf[0] = MATCH_ROM;
j3 17:b646b1e3970b 168 std::memcpy(&buf[1], romId, RomId::byteLen);
j3 17:b646b1e3970b 169 // send command and rom
j3 17:b646b1e3970b 170 result = OWWriteBlock(buf, 1 + RomId::byteLen);
j3 15:f6cb0d906fb6 171 }
j3 17:b646b1e3970b 172
j3 17:b646b1e3970b 173 return result;
j3 15:f6cb0d906fb6 174 }
j3 15:f6cb0d906fb6 175
j3 15:f6cb0d906fb6 176
j3 15:f6cb0d906fb6 177 //*********************************************************************
j3 23:e8e403d61359 178 OneWireMaster::CmdResult OneWireMaster::OWOverdriveSkipROM(void)
j3 15:f6cb0d906fb6 179 {
IanBenzMaxim 32:bce180b544ed 180 OneWireMaster::CmdResult result = OWSetSpeed(SPEED_STANDARD);
j3 15:f6cb0d906fb6 181
j3 23:e8e403d61359 182 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 183 {
j3 17:b646b1e3970b 184 result = OWReset();
j3 15:f6cb0d906fb6 185 }
j3 15:f6cb0d906fb6 186
j3 23:e8e403d61359 187 if (result == OneWireMaster::Success)
j3 17:b646b1e3970b 188 {
IanBenzMaxim 24:8942d8478d68 189 result = OWWriteByte(OVERDRIVE_SKIP_ROM);
j3 17:b646b1e3970b 190 }
j3 17:b646b1e3970b 191
j3 23:e8e403d61359 192 if (result == OneWireMaster::Success)
j3 17:b646b1e3970b 193 {
IanBenzMaxim 32:bce180b544ed 194 result = OWSetSpeed(SPEED_OVERDRIVE);
j3 17:b646b1e3970b 195 }
j3 17:b646b1e3970b 196
j3 17:b646b1e3970b 197 return result;
j3 15:f6cb0d906fb6 198 }
j3 15:f6cb0d906fb6 199
j3 15:f6cb0d906fb6 200
j3 15:f6cb0d906fb6 201 //*********************************************************************
j3 23:e8e403d61359 202 OneWireMaster::CmdResult OneWireMaster::OWOverdriveMatchROM(const RomId & romId)
j3 15:f6cb0d906fb6 203 {
j3 23:e8e403d61359 204 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 205
j3 17:b646b1e3970b 206 // use overdrive MatchROM
IanBenzMaxim 32:bce180b544ed 207 OWSetSpeed(SPEED_STANDARD);
j3 17:b646b1e3970b 208
j3 17:b646b1e3970b 209 result = OWReset();
j3 23:e8e403d61359 210 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 211 {
IanBenzMaxim 24:8942d8478d68 212 result = OWWriteByte(OVERDRIVE_MATCH_ROM);
j3 23:e8e403d61359 213 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 214 {
IanBenzMaxim 32:bce180b544ed 215 OWSetSpeed(SPEED_OVERDRIVE);
j3 17:b646b1e3970b 216 // send ROM
j3 17:b646b1e3970b 217 result = OWWriteBlock(romId, RomId::byteLen);
j3 15:f6cb0d906fb6 218 }
j3 15:f6cb0d906fb6 219 }
j3 17:b646b1e3970b 220 return result;
j3 15:f6cb0d906fb6 221 }
j3 15:f6cb0d906fb6 222
j3 15:f6cb0d906fb6 223
j3 15:f6cb0d906fb6 224 //*********************************************************************
j3 23:e8e403d61359 225 OneWireMaster::CmdResult OneWireMaster::OWResume(void)
j3 15:f6cb0d906fb6 226 {
j3 23:e8e403d61359 227 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 228
j3 17:b646b1e3970b 229 result = OWReset();
j3 23:e8e403d61359 230 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 231 {
IanBenzMaxim 24:8942d8478d68 232 result = OWWriteByte(RESUME);
j3 15:f6cb0d906fb6 233 }
j3 15:f6cb0d906fb6 234
j3 17:b646b1e3970b 235 return result;
j3 15:f6cb0d906fb6 236 }
j3 15:f6cb0d906fb6 237
j3 15:f6cb0d906fb6 238
IanBenzMaxim 32:bce180b544ed 239 OneWireMaster::CmdResult OneWireMaster::OWSearch(SearchState & searchState)
IanBenzMaxim 32:bce180b544ed 240 {
IanBenzMaxim 32:bce180b544ed 241 std::uint8_t id_bit_number;
IanBenzMaxim 32:bce180b544ed 242 std::uint8_t last_zero, rom_byte_number;
IanBenzMaxim 32:bce180b544ed 243 std::uint8_t id_bit, cmp_id_bit;
IanBenzMaxim 36:b6b5985a5e40 244 std::uint8_t rom_byte_mask;
IanBenzMaxim 32:bce180b544ed 245 bool search_result;
IanBenzMaxim 32:bce180b544ed 246 std::uint8_t crc8 = 0;
IanBenzMaxim 32:bce180b544ed 247 SearchDirection search_direction;
IanBenzMaxim 32:bce180b544ed 248
IanBenzMaxim 32:bce180b544ed 249 // initialize for search
IanBenzMaxim 32:bce180b544ed 250 id_bit_number = 1;
IanBenzMaxim 32:bce180b544ed 251 last_zero = 0;
IanBenzMaxim 32:bce180b544ed 252 rom_byte_number = 0;
IanBenzMaxim 32:bce180b544ed 253 rom_byte_mask = 1;
IanBenzMaxim 32:bce180b544ed 254 search_result = false;
IanBenzMaxim 32:bce180b544ed 255
IanBenzMaxim 32:bce180b544ed 256 // if the last call was not the last one
IanBenzMaxim 32:bce180b544ed 257 if (!searchState.last_device_flag)
IanBenzMaxim 32:bce180b544ed 258 {
IanBenzMaxim 32:bce180b544ed 259 // 1-Wire reset
IanBenzMaxim 32:bce180b544ed 260 OneWireMaster::CmdResult result = OWReset();
IanBenzMaxim 32:bce180b544ed 261 if (result != OneWireMaster::Success)
IanBenzMaxim 32:bce180b544ed 262 {
IanBenzMaxim 32:bce180b544ed 263 // reset the search
IanBenzMaxim 32:bce180b544ed 264 searchState.reset();
IanBenzMaxim 32:bce180b544ed 265 return result;
IanBenzMaxim 32:bce180b544ed 266 }
IanBenzMaxim 32:bce180b544ed 267
IanBenzMaxim 32:bce180b544ed 268 // issue the search command
IanBenzMaxim 32:bce180b544ed 269 OneWireMaster::OWWriteByte(SEARCH_ROM);
IanBenzMaxim 32:bce180b544ed 270
IanBenzMaxim 32:bce180b544ed 271 // loop to do the search
IanBenzMaxim 32:bce180b544ed 272 do
IanBenzMaxim 32:bce180b544ed 273 {
IanBenzMaxim 32:bce180b544ed 274 // if this discrepancy if before the Last Discrepancy
IanBenzMaxim 32:bce180b544ed 275 // on a previous next then pick the same as last time
IanBenzMaxim 32:bce180b544ed 276 if (id_bit_number < searchState.last_discrepancy)
IanBenzMaxim 32:bce180b544ed 277 {
IanBenzMaxim 32:bce180b544ed 278 if ((searchState.romId[rom_byte_number] & rom_byte_mask) > 0)
IanBenzMaxim 32:bce180b544ed 279 search_direction = DIRECTION_WRITE_ONE;
IanBenzMaxim 32:bce180b544ed 280 else
IanBenzMaxim 32:bce180b544ed 281 search_direction = DIRECTION_WRITE_ZERO;
IanBenzMaxim 32:bce180b544ed 282 }
IanBenzMaxim 32:bce180b544ed 283 else
IanBenzMaxim 32:bce180b544ed 284 {
IanBenzMaxim 32:bce180b544ed 285 // if equal to last pick 1, if not then pick 0
IanBenzMaxim 32:bce180b544ed 286 if (id_bit_number == searchState.last_discrepancy)
IanBenzMaxim 32:bce180b544ed 287 search_direction = DIRECTION_WRITE_ONE;
IanBenzMaxim 32:bce180b544ed 288 else
IanBenzMaxim 32:bce180b544ed 289 search_direction = DIRECTION_WRITE_ZERO;
IanBenzMaxim 32:bce180b544ed 290 }
IanBenzMaxim 32:bce180b544ed 291
IanBenzMaxim 32:bce180b544ed 292 // Peform a triple operation on the DS2465 which will perform 2 read bits and 1 write bit
IanBenzMaxim 32:bce180b544ed 293 result = OWTriplet(search_direction, id_bit, cmp_id_bit);
IanBenzMaxim 32:bce180b544ed 294 if (result != OneWireMaster::Success)
IanBenzMaxim 32:bce180b544ed 295 return result;
IanBenzMaxim 32:bce180b544ed 296
IanBenzMaxim 32:bce180b544ed 297 // check for no devices on 1-wire
IanBenzMaxim 32:bce180b544ed 298 if ((id_bit) && (cmp_id_bit))
IanBenzMaxim 32:bce180b544ed 299 break;
IanBenzMaxim 32:bce180b544ed 300 else
IanBenzMaxim 32:bce180b544ed 301 {
IanBenzMaxim 32:bce180b544ed 302 if ((!id_bit) && (!cmp_id_bit) && (search_direction == DIRECTION_WRITE_ZERO))
IanBenzMaxim 32:bce180b544ed 303 {
IanBenzMaxim 32:bce180b544ed 304 last_zero = id_bit_number;
IanBenzMaxim 32:bce180b544ed 305
IanBenzMaxim 32:bce180b544ed 306 // check for Last discrepancy in family
IanBenzMaxim 32:bce180b544ed 307 if (last_zero < 9)
IanBenzMaxim 32:bce180b544ed 308 searchState.last_family_discrepancy = last_zero;
IanBenzMaxim 32:bce180b544ed 309 }
IanBenzMaxim 32:bce180b544ed 310
IanBenzMaxim 32:bce180b544ed 311 // set or clear the bit in the ROM byte rom_byte_number
IanBenzMaxim 32:bce180b544ed 312 // with mask rom_byte_mask
IanBenzMaxim 32:bce180b544ed 313 if (search_direction == DIRECTION_WRITE_ONE)
IanBenzMaxim 32:bce180b544ed 314 searchState.romId[rom_byte_number] |= rom_byte_mask;
IanBenzMaxim 32:bce180b544ed 315 else
IanBenzMaxim 32:bce180b544ed 316 searchState.romId[rom_byte_number] &= (std::uint8_t)~rom_byte_mask;
IanBenzMaxim 32:bce180b544ed 317
IanBenzMaxim 32:bce180b544ed 318 // increment the byte counter id_bit_number
IanBenzMaxim 32:bce180b544ed 319 // and shift the mask rom_byte_mask
IanBenzMaxim 32:bce180b544ed 320 id_bit_number++;
IanBenzMaxim 32:bce180b544ed 321 rom_byte_mask <<= 1;
IanBenzMaxim 32:bce180b544ed 322
IanBenzMaxim 32:bce180b544ed 323 // if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask
IanBenzMaxim 32:bce180b544ed 324 if (rom_byte_mask == 0)
IanBenzMaxim 32:bce180b544ed 325 {
IanBenzMaxim 32:bce180b544ed 326 crc8 = RomId::calculateCRC8(crc8, searchState.romId[rom_byte_number]); // accumulate the CRC
IanBenzMaxim 32:bce180b544ed 327 rom_byte_number++;
IanBenzMaxim 32:bce180b544ed 328 rom_byte_mask = 1;
IanBenzMaxim 32:bce180b544ed 329 }
IanBenzMaxim 32:bce180b544ed 330 }
IanBenzMaxim 32:bce180b544ed 331 }
IanBenzMaxim 32:bce180b544ed 332 while(rom_byte_number < RomId::byteLen); // loop until through all ROM bytes 0-7
IanBenzMaxim 32:bce180b544ed 333
IanBenzMaxim 32:bce180b544ed 334 // if the search was successful then
IanBenzMaxim 32:bce180b544ed 335 if (!((id_bit_number <= (RomId::byteLen * 8)) || (crc8 != 0)))
IanBenzMaxim 32:bce180b544ed 336 {
IanBenzMaxim 32:bce180b544ed 337 // search successful so set m_last_discrepancy,m_last_device_flag,search_result
IanBenzMaxim 32:bce180b544ed 338 searchState.last_discrepancy = last_zero;
IanBenzMaxim 32:bce180b544ed 339
IanBenzMaxim 32:bce180b544ed 340 // check for last device
IanBenzMaxim 32:bce180b544ed 341 if (searchState.last_discrepancy == 0)
IanBenzMaxim 32:bce180b544ed 342 searchState.last_device_flag = true;
IanBenzMaxim 32:bce180b544ed 343
IanBenzMaxim 32:bce180b544ed 344 search_result = true;
IanBenzMaxim 32:bce180b544ed 345 }
IanBenzMaxim 32:bce180b544ed 346 }
IanBenzMaxim 32:bce180b544ed 347
IanBenzMaxim 32:bce180b544ed 348 // if no device found then reset counters so next 'search' will be like a first
IanBenzMaxim 32:bce180b544ed 349 if (!search_result || (searchState.romId.familyCode() == 0))
IanBenzMaxim 32:bce180b544ed 350 {
IanBenzMaxim 32:bce180b544ed 351 searchState.reset();
IanBenzMaxim 32:bce180b544ed 352 search_result = false;
IanBenzMaxim 32:bce180b544ed 353 }
IanBenzMaxim 32:bce180b544ed 354
IanBenzMaxim 32:bce180b544ed 355 return search_result ? OneWireMaster::Success : OneWireMaster::OperationFailure;
IanBenzMaxim 32:bce180b544ed 356 }
IanBenzMaxim 32:bce180b544ed 357
IanBenzMaxim 32:bce180b544ed 358
IanBenzMaxim 32:bce180b544ed 359 OneWireMaster::CmdResult OneWireMaster::OWTriplet(SearchDirection & search_direction, std::uint8_t & sbr, std::uint8_t & tsb)
IanBenzMaxim 32:bce180b544ed 360 {
IanBenzMaxim 32:bce180b544ed 361 CmdResult result;
IanBenzMaxim 32:bce180b544ed 362 result = OWReadBit(sbr);
IanBenzMaxim 32:bce180b544ed 363 if (result == Success)
IanBenzMaxim 32:bce180b544ed 364 result = OWReadBit(tsb);
IanBenzMaxim 32:bce180b544ed 365 if (result == Success)
IanBenzMaxim 32:bce180b544ed 366 {
IanBenzMaxim 32:bce180b544ed 367 if (sbr == 1)
IanBenzMaxim 32:bce180b544ed 368 search_direction = DIRECTION_WRITE_ONE;
IanBenzMaxim 32:bce180b544ed 369 else if ((sbr == 0) && (tsb == 1))
IanBenzMaxim 32:bce180b544ed 370 search_direction = DIRECTION_WRITE_ZERO;
IanBenzMaxim 32:bce180b544ed 371 // else: use search_direction parameter
IanBenzMaxim 32:bce180b544ed 372
IanBenzMaxim 32:bce180b544ed 373 result = OWWriteBit((search_direction == DIRECTION_WRITE_ONE) ? 1 : 0);
IanBenzMaxim 32:bce180b544ed 374 }
IanBenzMaxim 32:bce180b544ed 375 return result;
IanBenzMaxim 32:bce180b544ed 376 }
IanBenzMaxim 32:bce180b544ed 377
IanBenzMaxim 32:bce180b544ed 378
j3 17:b646b1e3970b 379 //--------------------------------------------------------------------------
j3 17:b646b1e3970b 380 // Calculate a new CRC16 from the input data shorteger. Return the current
j3 17:b646b1e3970b 381 // CRC16 and also update the global variable CRC16.
j3 17:b646b1e3970b 382 //
j3 17:b646b1e3970b 383 uint16_t OneWireMaster::calculateCRC16(uint16_t CRC16, uint16_t data)
j3 15:f6cb0d906fb6 384 {
j3 17:b646b1e3970b 385 data = (data ^ (CRC16 & 0xff)) & 0xff;
j3 17:b646b1e3970b 386 CRC16 >>= 8;
j3 17:b646b1e3970b 387
j3 17:b646b1e3970b 388 if (_oddparity[data & 0xf] ^ _oddparity[data >> 4])
j3 17:b646b1e3970b 389 CRC16 ^= 0xc001;
j3 17:b646b1e3970b 390
j3 17:b646b1e3970b 391 data <<= 6;
j3 17:b646b1e3970b 392 CRC16 ^= data;
j3 17:b646b1e3970b 393 data <<= 1;
j3 17:b646b1e3970b 394 CRC16 ^= data;
j3 17:b646b1e3970b 395
j3 17:b646b1e3970b 396 return CRC16;
j3 15:f6cb0d906fb6 397 }
j3 15:f6cb0d906fb6 398
j3 17:b646b1e3970b 399 uint16_t OneWireMaster::calculateCRC16(const uint8_t * data, size_t data_offset, size_t data_len, uint16_t crc)
j3 17:b646b1e3970b 400 {
j3 17:b646b1e3970b 401 for (size_t i = data_offset; i < (data_len + data_offset); i++)
j3 17:b646b1e3970b 402 crc = calculateCRC16(crc, data[i]);
j3 17:b646b1e3970b 403 return crc;
IanBenzMaxim 21:00c94aeb533e 404 }