Maxim Integrated / OneWire

1-Wire® library for mbed. Complete 1-Wire library that supports our silicon masters along with a bit-bang master on the MAX32600MBED platform with one common interface for mbed. Slave support has also been included and more slaves will be added as time permits.

Dependents:   MAXREFDES131_Qt_Demo MAX32630FTHR_iButton_uSD_Logger MAX32630FTHR_DS18B20_uSD_Logger MAXREFDES130_131_Demo ... more

Superseded by MaximInterface.

OneWire_Masters/OneWireMaster.cpp@42:698635a0d073, 2016-04-06 (annotated)

Committer:
j3
Date:
Wed Apr 06 04:30:37 2016 +0000
Revision:
42:698635a0d073
Parent:
36:b6b5985a5e40
Child:
43:23017dcd2ec3
set romId of local searchState in OWVerify = too romId being passed to OWVerify (rom ID of device being verified)

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 42:698635a0d073 66
j3 42:698635a0d073 67 searchState.romId = romId;
j3 15:f6cb0d906fb6 68
j3 15:f6cb0d906fb6 69 // set search to find the same device
IanBenzMaxim 32:bce180b544ed 70 searchState.last_discrepancy = 64;
IanBenzMaxim 32:bce180b544ed 71 searchState.last_device_flag = false;
j3 15:f6cb0d906fb6 72
IanBenzMaxim 32:bce180b544ed 73 result = OWSearch(searchState);
j3 23:e8e403d61359 74 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 75 {
j3 15:f6cb0d906fb6 76 // check if same device found
IanBenzMaxim 32:bce180b544ed 77 if (romId != searchState.romId)
j3 15:f6cb0d906fb6 78 {
j3 23:e8e403d61359 79 result = OneWireMaster::OperationFailure;
j3 15:f6cb0d906fb6 80 }
j3 15:f6cb0d906fb6 81 }
j3 15:f6cb0d906fb6 82
j3 17:b646b1e3970b 83 return result;
j3 15:f6cb0d906fb6 84 }
j3 15:f6cb0d906fb6 85
j3 15:f6cb0d906fb6 86
j3 15:f6cb0d906fb6 87 //*********************************************************************
IanBenzMaxim 32:bce180b544ed 88 void OneWireMaster::OWTargetSetup(SearchState & searchState)
j3 15:f6cb0d906fb6 89 {
j3 15:f6cb0d906fb6 90 // set the search state to find SearchFamily type devices
IanBenzMaxim 32:bce180b544ed 91 std::uint8_t familyCode = searchState.romId.familyCode();
IanBenzMaxim 32:bce180b544ed 92 searchState.reset();
IanBenzMaxim 32:bce180b544ed 93 searchState.romId.setFamilyCode(familyCode);
IanBenzMaxim 32:bce180b544ed 94 searchState.last_discrepancy = 64;
j3 15:f6cb0d906fb6 95 }
j3 5:ce108eeb878d 96
j3 5:ce108eeb878d 97
j3 5:ce108eeb878d 98 //*********************************************************************
IanBenzMaxim 32:bce180b544ed 99 void OneWireMaster::OWFamilySkipSetup(SearchState & searchState)
j3 15:f6cb0d906fb6 100 {
j3 15:f6cb0d906fb6 101 // set the Last discrepancy to last family discrepancy
IanBenzMaxim 32:bce180b544ed 102 searchState.last_discrepancy = searchState.last_family_discrepancy;
j3 17:b646b1e3970b 103
j3 15:f6cb0d906fb6 104 // clear the last family discrpepancy
IanBenzMaxim 32:bce180b544ed 105 searchState.last_family_discrepancy = 0;
j3 17:b646b1e3970b 106
j3 15:f6cb0d906fb6 107 // check for end of list
IanBenzMaxim 32:bce180b544ed 108 if (searchState.last_discrepancy == 0)
j3 15:f6cb0d906fb6 109 {
IanBenzMaxim 32:bce180b544ed 110 searchState.last_device_flag = true;
j3 15:f6cb0d906fb6 111 }
j3 15:f6cb0d906fb6 112 }
j3 15:f6cb0d906fb6 113
j3 15:f6cb0d906fb6 114
j3 15:f6cb0d906fb6 115 //*********************************************************************
j3 23:e8e403d61359 116 OneWireMaster::CmdResult OneWireMaster::OWReadROM(RomId & romId)
j3 15:f6cb0d906fb6 117 {
j3 23:e8e403d61359 118 OneWireMaster::CmdResult result;
j3 17:b646b1e3970b 119 uint8_t buf[2 + RomId::byteLen];
j3 17:b646b1e3970b 120
j3 17:b646b1e3970b 121 result = OWReset();
j3 23:e8e403d61359 122 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 123 {
IanBenzMaxim 24:8942d8478d68 124 result = OWWriteByte(READ_ROM);
j3 17:b646b1e3970b 125 }
j3 17:b646b1e3970b 126
j3 17:b646b1e3970b 127 // read the ROM
j3 23:e8e403d61359 128 if (result == OneWireMaster::Success)
j3 17:b646b1e3970b 129 {
j3 17:b646b1e3970b 130 result = OWReadBlock(buf, RomId::byteLen);
j3 15:f6cb0d906fb6 131 }
j3 15:f6cb0d906fb6 132
j3 17:b646b1e3970b 133 // verify CRC8
IanBenzMaxim 24:8942d8478d68 134 if ((result == OneWireMaster::Success) && (RomId::calculateCRC8(buf, RomId::byteLen) == 0))
j3 17:b646b1e3970b 135 {
j3 17:b646b1e3970b 136 romId = RomId(reinterpret_cast<std::uint8_t (&)[RomId::byteLen]>(buf[0]));
j3 17:b646b1e3970b 137 }
j3 17:b646b1e3970b 138
j3 17:b646b1e3970b 139 return result;
j3 15:f6cb0d906fb6 140 }
j3 15:f6cb0d906fb6 141
j3 15:f6cb0d906fb6 142
j3 15:f6cb0d906fb6 143 //*********************************************************************
j3 23:e8e403d61359 144 OneWireMaster::CmdResult OneWireMaster::OWSkipROM(void)
j3 15:f6cb0d906fb6 145 {
j3 23:e8e403d61359 146 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 147
j3 17:b646b1e3970b 148 result = OWReset();
j3 23:e8e403d61359 149 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 150 {
IanBenzMaxim 24:8942d8478d68 151 result = OWWriteByte(SKIP_ROM);
j3 15:f6cb0d906fb6 152 }
j3 15:f6cb0d906fb6 153
j3 17:b646b1e3970b 154 return result;
j3 15:f6cb0d906fb6 155 }
j3 15:f6cb0d906fb6 156
j3 15:f6cb0d906fb6 157
j3 15:f6cb0d906fb6 158 //*********************************************************************
j3 23:e8e403d61359 159 OneWireMaster::CmdResult OneWireMaster::OWMatchROM(const RomId & romId)
j3 15:f6cb0d906fb6 160 {
j3 23:e8e403d61359 161 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 162
j3 17:b646b1e3970b 163 uint8_t buf[1 + RomId::byteLen];
j3 17:b646b1e3970b 164
j3 17:b646b1e3970b 165 // use MatchROM
j3 17:b646b1e3970b 166 result = OWReset();
j3 23:e8e403d61359 167 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 168 {
IanBenzMaxim 24:8942d8478d68 169 buf[0] = MATCH_ROM;
j3 17:b646b1e3970b 170 std::memcpy(&buf[1], romId, RomId::byteLen);
j3 17:b646b1e3970b 171 // send command and rom
j3 17:b646b1e3970b 172 result = OWWriteBlock(buf, 1 + RomId::byteLen);
j3 15:f6cb0d906fb6 173 }
j3 17:b646b1e3970b 174
j3 17:b646b1e3970b 175 return result;
j3 15:f6cb0d906fb6 176 }
j3 15:f6cb0d906fb6 177
j3 15:f6cb0d906fb6 178
j3 15:f6cb0d906fb6 179 //*********************************************************************
j3 23:e8e403d61359 180 OneWireMaster::CmdResult OneWireMaster::OWOverdriveSkipROM(void)
j3 15:f6cb0d906fb6 181 {
IanBenzMaxim 32:bce180b544ed 182 OneWireMaster::CmdResult result = OWSetSpeed(SPEED_STANDARD);
j3 15:f6cb0d906fb6 183
j3 23:e8e403d61359 184 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 185 {
j3 17:b646b1e3970b 186 result = OWReset();
j3 15:f6cb0d906fb6 187 }
j3 15:f6cb0d906fb6 188
j3 23:e8e403d61359 189 if (result == OneWireMaster::Success)
j3 17:b646b1e3970b 190 {
IanBenzMaxim 24:8942d8478d68 191 result = OWWriteByte(OVERDRIVE_SKIP_ROM);
j3 17:b646b1e3970b 192 }
j3 17:b646b1e3970b 193
j3 23:e8e403d61359 194 if (result == OneWireMaster::Success)
j3 17:b646b1e3970b 195 {
IanBenzMaxim 32:bce180b544ed 196 result = OWSetSpeed(SPEED_OVERDRIVE);
j3 17:b646b1e3970b 197 }
j3 17:b646b1e3970b 198
j3 17:b646b1e3970b 199 return result;
j3 15:f6cb0d906fb6 200 }
j3 15:f6cb0d906fb6 201
j3 15:f6cb0d906fb6 202
j3 15:f6cb0d906fb6 203 //*********************************************************************
j3 23:e8e403d61359 204 OneWireMaster::CmdResult OneWireMaster::OWOverdriveMatchROM(const RomId & romId)
j3 15:f6cb0d906fb6 205 {
j3 23:e8e403d61359 206 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 207
j3 17:b646b1e3970b 208 // use overdrive MatchROM
IanBenzMaxim 32:bce180b544ed 209 OWSetSpeed(SPEED_STANDARD);
j3 17:b646b1e3970b 210
j3 17:b646b1e3970b 211 result = OWReset();
j3 23:e8e403d61359 212 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 213 {
IanBenzMaxim 24:8942d8478d68 214 result = OWWriteByte(OVERDRIVE_MATCH_ROM);
j3 23:e8e403d61359 215 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 216 {
IanBenzMaxim 32:bce180b544ed 217 OWSetSpeed(SPEED_OVERDRIVE);
j3 17:b646b1e3970b 218 // send ROM
j3 17:b646b1e3970b 219 result = OWWriteBlock(romId, RomId::byteLen);
j3 15:f6cb0d906fb6 220 }
j3 15:f6cb0d906fb6 221 }
j3 17:b646b1e3970b 222 return result;
j3 15:f6cb0d906fb6 223 }
j3 15:f6cb0d906fb6 224
j3 15:f6cb0d906fb6 225
j3 15:f6cb0d906fb6 226 //*********************************************************************
j3 23:e8e403d61359 227 OneWireMaster::CmdResult OneWireMaster::OWResume(void)
j3 15:f6cb0d906fb6 228 {
j3 23:e8e403d61359 229 OneWireMaster::CmdResult result;
j3 15:f6cb0d906fb6 230
j3 17:b646b1e3970b 231 result = OWReset();
j3 23:e8e403d61359 232 if (result == OneWireMaster::Success)
j3 15:f6cb0d906fb6 233 {
IanBenzMaxim 24:8942d8478d68 234 result = OWWriteByte(RESUME);
j3 15:f6cb0d906fb6 235 }
j3 15:f6cb0d906fb6 236
j3 17:b646b1e3970b 237 return result;
j3 15:f6cb0d906fb6 238 }
j3 15:f6cb0d906fb6 239
j3 15:f6cb0d906fb6 240
IanBenzMaxim 32:bce180b544ed 241 OneWireMaster::CmdResult OneWireMaster::OWSearch(SearchState & searchState)
IanBenzMaxim 32:bce180b544ed 242 {
IanBenzMaxim 32:bce180b544ed 243 std::uint8_t id_bit_number;
IanBenzMaxim 32:bce180b544ed 244 std::uint8_t last_zero, rom_byte_number;
IanBenzMaxim 32:bce180b544ed 245 std::uint8_t id_bit, cmp_id_bit;
IanBenzMaxim 36:b6b5985a5e40 246 std::uint8_t rom_byte_mask;
IanBenzMaxim 32:bce180b544ed 247 bool search_result;
IanBenzMaxim 32:bce180b544ed 248 std::uint8_t crc8 = 0;
IanBenzMaxim 32:bce180b544ed 249 SearchDirection search_direction;
IanBenzMaxim 32:bce180b544ed 250
IanBenzMaxim 32:bce180b544ed 251 // initialize for search
IanBenzMaxim 32:bce180b544ed 252 id_bit_number = 1;
IanBenzMaxim 32:bce180b544ed 253 last_zero = 0;
IanBenzMaxim 32:bce180b544ed 254 rom_byte_number = 0;
IanBenzMaxim 32:bce180b544ed 255 rom_byte_mask = 1;
IanBenzMaxim 32:bce180b544ed 256 search_result = false;
IanBenzMaxim 32:bce180b544ed 257
IanBenzMaxim 32:bce180b544ed 258 // if the last call was not the last one
IanBenzMaxim 32:bce180b544ed 259 if (!searchState.last_device_flag)
IanBenzMaxim 32:bce180b544ed 260 {
IanBenzMaxim 32:bce180b544ed 261 // 1-Wire reset
IanBenzMaxim 32:bce180b544ed 262 OneWireMaster::CmdResult result = OWReset();
IanBenzMaxim 32:bce180b544ed 263 if (result != OneWireMaster::Success)
IanBenzMaxim 32:bce180b544ed 264 {
IanBenzMaxim 32:bce180b544ed 265 // reset the search
IanBenzMaxim 32:bce180b544ed 266 searchState.reset();
IanBenzMaxim 32:bce180b544ed 267 return result;
IanBenzMaxim 32:bce180b544ed 268 }
IanBenzMaxim 32:bce180b544ed 269
IanBenzMaxim 32:bce180b544ed 270 // issue the search command
IanBenzMaxim 32:bce180b544ed 271 OneWireMaster::OWWriteByte(SEARCH_ROM);
IanBenzMaxim 32:bce180b544ed 272
IanBenzMaxim 32:bce180b544ed 273 // loop to do the search
IanBenzMaxim 32:bce180b544ed 274 do
IanBenzMaxim 32:bce180b544ed 275 {
IanBenzMaxim 32:bce180b544ed 276 // if this discrepancy if before the Last Discrepancy
IanBenzMaxim 32:bce180b544ed 277 // on a previous next then pick the same as last time
IanBenzMaxim 32:bce180b544ed 278 if (id_bit_number < searchState.last_discrepancy)
IanBenzMaxim 32:bce180b544ed 279 {
IanBenzMaxim 32:bce180b544ed 280 if ((searchState.romId[rom_byte_number] & rom_byte_mask) > 0)
IanBenzMaxim 32:bce180b544ed 281 search_direction = DIRECTION_WRITE_ONE;
IanBenzMaxim 32:bce180b544ed 282 else
IanBenzMaxim 32:bce180b544ed 283 search_direction = DIRECTION_WRITE_ZERO;
IanBenzMaxim 32:bce180b544ed 284 }
IanBenzMaxim 32:bce180b544ed 285 else
IanBenzMaxim 32:bce180b544ed 286 {
IanBenzMaxim 32:bce180b544ed 287 // if equal to last pick 1, if not then pick 0
IanBenzMaxim 32:bce180b544ed 288 if (id_bit_number == searchState.last_discrepancy)
IanBenzMaxim 32:bce180b544ed 289 search_direction = DIRECTION_WRITE_ONE;
IanBenzMaxim 32:bce180b544ed 290 else
IanBenzMaxim 32:bce180b544ed 291 search_direction = DIRECTION_WRITE_ZERO;
IanBenzMaxim 32:bce180b544ed 292 }
IanBenzMaxim 32:bce180b544ed 293
IanBenzMaxim 32:bce180b544ed 294 // Peform a triple operation on the DS2465 which will perform 2 read bits and 1 write bit
IanBenzMaxim 32:bce180b544ed 295 result = OWTriplet(search_direction, id_bit, cmp_id_bit);
IanBenzMaxim 32:bce180b544ed 296 if (result != OneWireMaster::Success)
IanBenzMaxim 32:bce180b544ed 297 return result;
IanBenzMaxim 32:bce180b544ed 298
IanBenzMaxim 32:bce180b544ed 299 // check for no devices on 1-wire
IanBenzMaxim 32:bce180b544ed 300 if ((id_bit) && (cmp_id_bit))
IanBenzMaxim 32:bce180b544ed 301 break;
IanBenzMaxim 32:bce180b544ed 302 else
IanBenzMaxim 32:bce180b544ed 303 {
IanBenzMaxim 32:bce180b544ed 304 if ((!id_bit) && (!cmp_id_bit) && (search_direction == DIRECTION_WRITE_ZERO))
IanBenzMaxim 32:bce180b544ed 305 {
IanBenzMaxim 32:bce180b544ed 306 last_zero = id_bit_number;
IanBenzMaxim 32:bce180b544ed 307
IanBenzMaxim 32:bce180b544ed 308 // check for Last discrepancy in family
IanBenzMaxim 32:bce180b544ed 309 if (last_zero < 9)
IanBenzMaxim 32:bce180b544ed 310 searchState.last_family_discrepancy = last_zero;
IanBenzMaxim 32:bce180b544ed 311 }
IanBenzMaxim 32:bce180b544ed 312
IanBenzMaxim 32:bce180b544ed 313 // set or clear the bit in the ROM byte rom_byte_number
IanBenzMaxim 32:bce180b544ed 314 // with mask rom_byte_mask
IanBenzMaxim 32:bce180b544ed 315 if (search_direction == DIRECTION_WRITE_ONE)
IanBenzMaxim 32:bce180b544ed 316 searchState.romId[rom_byte_number] |= rom_byte_mask;
IanBenzMaxim 32:bce180b544ed 317 else
IanBenzMaxim 32:bce180b544ed 318 searchState.romId[rom_byte_number] &= (std::uint8_t)~rom_byte_mask;
IanBenzMaxim 32:bce180b544ed 319
IanBenzMaxim 32:bce180b544ed 320 // increment the byte counter id_bit_number
IanBenzMaxim 32:bce180b544ed 321 // and shift the mask rom_byte_mask
IanBenzMaxim 32:bce180b544ed 322 id_bit_number++;
IanBenzMaxim 32:bce180b544ed 323 rom_byte_mask <<= 1;
IanBenzMaxim 32:bce180b544ed 324
IanBenzMaxim 32:bce180b544ed 325 // if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask
IanBenzMaxim 32:bce180b544ed 326 if (rom_byte_mask == 0)
IanBenzMaxim 32:bce180b544ed 327 {
IanBenzMaxim 32:bce180b544ed 328 crc8 = RomId::calculateCRC8(crc8, searchState.romId[rom_byte_number]); // accumulate the CRC
IanBenzMaxim 32:bce180b544ed 329 rom_byte_number++;
IanBenzMaxim 32:bce180b544ed 330 rom_byte_mask = 1;
IanBenzMaxim 32:bce180b544ed 331 }
IanBenzMaxim 32:bce180b544ed 332 }
IanBenzMaxim 32:bce180b544ed 333 }
IanBenzMaxim 32:bce180b544ed 334 while(rom_byte_number < RomId::byteLen); // loop until through all ROM bytes 0-7
IanBenzMaxim 32:bce180b544ed 335
IanBenzMaxim 32:bce180b544ed 336 // if the search was successful then
IanBenzMaxim 32:bce180b544ed 337 if (!((id_bit_number <= (RomId::byteLen * 8)) || (crc8 != 0)))
IanBenzMaxim 32:bce180b544ed 338 {
IanBenzMaxim 32:bce180b544ed 339 // search successful so set m_last_discrepancy,m_last_device_flag,search_result
IanBenzMaxim 32:bce180b544ed 340 searchState.last_discrepancy = last_zero;
IanBenzMaxim 32:bce180b544ed 341
IanBenzMaxim 32:bce180b544ed 342 // check for last device
IanBenzMaxim 32:bce180b544ed 343 if (searchState.last_discrepancy == 0)
IanBenzMaxim 32:bce180b544ed 344 searchState.last_device_flag = true;
IanBenzMaxim 32:bce180b544ed 345
IanBenzMaxim 32:bce180b544ed 346 search_result = true;
IanBenzMaxim 32:bce180b544ed 347 }
IanBenzMaxim 32:bce180b544ed 348 }
IanBenzMaxim 32:bce180b544ed 349
IanBenzMaxim 32:bce180b544ed 350 // if no device found then reset counters so next 'search' will be like a first
IanBenzMaxim 32:bce180b544ed 351 if (!search_result || (searchState.romId.familyCode() == 0))
IanBenzMaxim 32:bce180b544ed 352 {
IanBenzMaxim 32:bce180b544ed 353 searchState.reset();
IanBenzMaxim 32:bce180b544ed 354 search_result = false;
IanBenzMaxim 32:bce180b544ed 355 }
IanBenzMaxim 32:bce180b544ed 356
IanBenzMaxim 32:bce180b544ed 357 return search_result ? OneWireMaster::Success : OneWireMaster::OperationFailure;
IanBenzMaxim 32:bce180b544ed 358 }
IanBenzMaxim 32:bce180b544ed 359
IanBenzMaxim 32:bce180b544ed 360
IanBenzMaxim 32:bce180b544ed 361 OneWireMaster::CmdResult OneWireMaster::OWTriplet(SearchDirection & search_direction, std::uint8_t & sbr, std::uint8_t & tsb)
IanBenzMaxim 32:bce180b544ed 362 {
IanBenzMaxim 32:bce180b544ed 363 CmdResult result;
IanBenzMaxim 32:bce180b544ed 364 result = OWReadBit(sbr);
IanBenzMaxim 32:bce180b544ed 365 if (result == Success)
IanBenzMaxim 32:bce180b544ed 366 result = OWReadBit(tsb);
IanBenzMaxim 32:bce180b544ed 367 if (result == Success)
IanBenzMaxim 32:bce180b544ed 368 {
IanBenzMaxim 32:bce180b544ed 369 if (sbr == 1)
IanBenzMaxim 32:bce180b544ed 370 search_direction = DIRECTION_WRITE_ONE;
IanBenzMaxim 32:bce180b544ed 371 else if ((sbr == 0) && (tsb == 1))
IanBenzMaxim 32:bce180b544ed 372 search_direction = DIRECTION_WRITE_ZERO;
IanBenzMaxim 32:bce180b544ed 373 // else: use search_direction parameter
IanBenzMaxim 32:bce180b544ed 374
IanBenzMaxim 32:bce180b544ed 375 result = OWWriteBit((search_direction == DIRECTION_WRITE_ONE) ? 1 : 0);
IanBenzMaxim 32:bce180b544ed 376 }
IanBenzMaxim 32:bce180b544ed 377 return result;
IanBenzMaxim 32:bce180b544ed 378 }
IanBenzMaxim 32:bce180b544ed 379
IanBenzMaxim 32:bce180b544ed 380
j3 17:b646b1e3970b 381 //--------------------------------------------------------------------------
j3 17:b646b1e3970b 382 // Calculate a new CRC16 from the input data shorteger. Return the current
j3 17:b646b1e3970b 383 // CRC16 and also update the global variable CRC16.
j3 17:b646b1e3970b 384 //
j3 17:b646b1e3970b 385 uint16_t OneWireMaster::calculateCRC16(uint16_t CRC16, uint16_t data)
j3 15:f6cb0d906fb6 386 {
j3 17:b646b1e3970b 387 data = (data ^ (CRC16 & 0xff)) & 0xff;
j3 17:b646b1e3970b 388 CRC16 >>= 8;
j3 17:b646b1e3970b 389
j3 17:b646b1e3970b 390 if (_oddparity[data & 0xf] ^ _oddparity[data >> 4])
j3 17:b646b1e3970b 391 CRC16 ^= 0xc001;
j3 17:b646b1e3970b 392
j3 17:b646b1e3970b 393 data <<= 6;
j3 17:b646b1e3970b 394 CRC16 ^= data;
j3 17:b646b1e3970b 395 data <<= 1;
j3 17:b646b1e3970b 396 CRC16 ^= data;
j3 17:b646b1e3970b 397
j3 17:b646b1e3970b 398 return CRC16;
j3 15:f6cb0d906fb6 399 }
j3 15:f6cb0d906fb6 400
j3 17:b646b1e3970b 401 uint16_t OneWireMaster::calculateCRC16(const uint8_t * data, size_t data_offset, size_t data_len, uint16_t crc)
j3 17:b646b1e3970b 402 {
j3 17:b646b1e3970b 403 for (size_t i = data_offset; i < (data_len + data_offset); i++)
j3 17:b646b1e3970b 404 crc = calculateCRC16(crc, data[i]);
j3 17:b646b1e3970b 405 return crc;
IanBenzMaxim 21:00c94aeb533e 406 }