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Superseded by MaximInterface.
Masters/OneWireMaster.cpp
- Committer:
- IanBenzMaxim
- Date:
- 2016-05-16
- Revision:
- 77:529edb329ee0
- Parent:
- 76:84e6c4994e29
- Child:
- 78:0cbbac7f2016
File content as of revision 77:529edb329ee0:
/******************************************************************//** * Copyright (C) 2016 Maxim Integrated Products, Inc., 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 MAXIM INTEGRATED 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 Maxim Integrated * Products, Inc. shall not be used except as stated in the Maxim Integrated * Products, Inc. Branding Policy. * * The mere transfer of this software does not imply any licenses * of trade secrets, proprietary technology, copyrights, patents, * trademarks, maskwork rights, or any other form of intellectual * property whatsoever. Maxim Integrated Products, Inc. retains all * ownership rights. **********************************************************************/ #include "OneWireMaster.h" #include "RomId.h" using OneWire::OneWireMaster; enum OwRomCmd { ReadRomCmd = 0x33, MatchRomCmd = 0x55, SearchRomCmd = 0xF0, SkipRomCmd = 0xCC, ResumeCmd = 0xA5, OverdriveSkipRomCmd = 0x3C, OverdriveMatchRomCmd = 0x69 }; OneWireMaster::CmdResult OneWireMaster::OWWriteBlock(const uint8_t *sendBuf, uint8_t sendLen) { CmdResult result; for (uint8_t idx = 0; idx < sendLen; idx++) { result = OWWriteByte(sendBuf[idx]); if (result != Success) { break; } } return result; } OneWireMaster::CmdResult OneWireMaster::OWReadBlock(uint8_t *recvBuf, uint8_t recvLen) { CmdResult result; for (uint8_t idx = 0; idx < recvLen; idx++) { result = OWReadByte(recvBuf[idx]); if (result != Success) { break; } } return result; } OneWireMaster::CmdResult OneWireMaster::OWTriplet(SearchDirection & searchDirection, uint8_t & sbr, uint8_t & tsb) { CmdResult result; result = OWReadBit(sbr); if (result == Success) { result = OWReadBit(tsb); } if (result == Success) { if (sbr) { searchDirection = WriteOne; } else if (tsb) { searchDirection = WriteZero; } // else: use search_direction parameter result = OWWriteBit((searchDirection == WriteOne) ? 1 : 0); } return result; } uint16_t OneWireMaster::calculateCrc16(uint16_t crc16, uint16_t data) { const uint16_t oddparity[] = { 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 }; data = (data ^ (crc16 & 0xff)) & 0xff; crc16 >>= 8; if (oddparity[data & 0xf] ^ oddparity[data >> 4]) { crc16 ^= 0xc001; } data <<= 6; crc16 ^= data; data <<= 1; crc16 ^= data; return crc16; } uint16_t OneWireMaster::calculateCrc16(const uint8_t * data, size_t dataOffset, size_t dataLen, uint16_t crc) { for (size_t i = dataOffset; i < (dataLen + dataOffset); i++) { crc = calculateCrc16(crc, data[i]); } return crc; } void OneWireMaster::SearchState::reset() { last_discrepancy = 0; last_device_flag = false; last_family_discrepancy = 0; romId.reset(); } void OneWireMaster::SearchState::findFamily(uint8_t familyCode) { reset(); romId.setFamilyCode(familyCode); last_discrepancy = 64; } void OneWireMaster::SearchState::skipCurrentFamily() { // set the Last discrepancy to last family discrepancy last_discrepancy = last_family_discrepancy; // clear the last family discrpepancy last_family_discrepancy = 0; // check for end of list if (last_discrepancy == 0) { last_device_flag = true; } } OneWireMaster::CmdResult OneWireMaster::OWFirst(SearchState & searchState) { // Reset and begin a new search searchState.reset(); return OWSearch(searchState); } OneWireMaster::CmdResult OneWireMaster::OWNext(SearchState & searchState) { // Continue the previous search return OWSearch(searchState); } OneWireMaster::CmdResult OneWireMaster::OWVerify(const RomId & romId) { OneWireMaster::CmdResult result; SearchState searchState; searchState.romId = romId; // set search to find the same device searchState.last_discrepancy = 64; searchState.last_device_flag = false; result = OWSearch(searchState); if (result == OneWireMaster::Success) { // check if same device found if (romId != searchState.romId) { result = OneWireMaster::OperationFailure; } } return result; } OneWireMaster::CmdResult OneWireMaster::OWReadRom(RomId & romId) { OneWireMaster::CmdResult result; RomId readId; result = OWReset(); if (result == OneWireMaster::Success) { result = OWWriteByte(ReadRomCmd); } // read the ROM if (result == OneWireMaster::Success) { result = OWReadBlock(readId, RomId::byteLen); } // verify CRC8 if (result == OneWireMaster::Success) { if (readId.crc8Valid()) { romId = readId; } else { result = OneWireMaster::OperationFailure; } } return result; } OneWireMaster::CmdResult OneWireMaster::OWSkipRom() { OneWireMaster::CmdResult result; result = OWReset(); if (result == OneWireMaster::Success) { result = OWWriteByte(SkipRomCmd); } return result; } OneWireMaster::CmdResult OneWireMaster::OWMatchRom(const RomId & romId) { OneWireMaster::CmdResult result; uint8_t buf[1 + RomId::byteLen]; // use MatchROM result = OWReset(); if (result == OneWireMaster::Success) { buf[0] = MatchRomCmd; std::memcpy(&buf[1], romId, RomId::byteLen); // send command and rom result = OWWriteBlock(buf, 1 + RomId::byteLen); } return result; } OneWireMaster::CmdResult OneWireMaster::OWOverdriveSkipRom() { OneWireMaster::CmdResult result = OWSetSpeed(OneWireMaster::StandardSpeed); if (result == OneWireMaster::Success) { result = OWReset(); } if (result == OneWireMaster::Success) { result = OWWriteByte(OverdriveSkipRomCmd); } if (result == OneWireMaster::Success) { result = OWSetSpeed(OneWireMaster::OverdriveSpeed); } return result; } OneWireMaster::CmdResult OneWireMaster::OWOverdriveMatchRom(const RomId & romId) { OneWireMaster::CmdResult result; // use overdrive MatchROM OWSetSpeed(OneWireMaster::StandardSpeed); result = OWReset(); if (result == OneWireMaster::Success) { result = OWWriteByte(OverdriveMatchRomCmd); if (result == OneWireMaster::Success) { OWSetSpeed(OneWireMaster::OverdriveSpeed); // send ROM result = OWWriteBlock(romId, RomId::byteLen); } } return result; } OneWireMaster::CmdResult OneWireMaster::OWResume() { OneWireMaster::CmdResult result; result = OWReset(); if (result == OneWireMaster::Success) { result = OWWriteByte(ResumeCmd); } return result; } OneWireMaster::CmdResult OneWireMaster::OWSearch(SearchState & searchState) { uint8_t id_bit_number; uint8_t last_zero, rom_byte_number; uint8_t id_bit, cmp_id_bit; uint8_t rom_byte_mask; bool search_result; uint8_t crc8 = 0; OneWireMaster::SearchDirection search_direction; // initialize for search id_bit_number = 1; last_zero = 0; rom_byte_number = 0; rom_byte_mask = 1; search_result = false; // if the last call was not the last one if (!searchState.last_device_flag) { // 1-Wire reset OneWireMaster::CmdResult result = OWReset(); if (result != OneWireMaster::Success) { // reset the search searchState.reset(); return result; } // issue the search command OWWriteByte(SearchRomCmd); // loop to do the search do { // if this discrepancy if before the Last Discrepancy // on a previous next then pick the same as last time if (id_bit_number < searchState.last_discrepancy) { if ((searchState.romId[rom_byte_number] & rom_byte_mask) > 0) { search_direction = OneWireMaster::WriteOne; } else { search_direction = OneWireMaster::WriteZero; } } else { // if equal to last pick 1, if not then pick 0 if (id_bit_number == searchState.last_discrepancy) { search_direction = OneWireMaster::WriteOne; } else { search_direction = OneWireMaster::WriteZero; } } // Peform a triple operation on the DS2465 which will perform 2 read bits and 1 write bit result = OWTriplet(search_direction, id_bit, cmp_id_bit); if (result != OneWireMaster::Success) { return result; } // check for no devices on 1-wire if (id_bit && cmp_id_bit) { break; } else { if (!id_bit && !cmp_id_bit && (search_direction == OneWireMaster::WriteZero)) { last_zero = id_bit_number; // check for Last discrepancy in family if (last_zero < 9) { searchState.last_family_discrepancy = last_zero; } } // set or clear the bit in the ROM byte rom_byte_number // with mask rom_byte_mask if (search_direction == OneWireMaster::WriteOne) { searchState.romId[rom_byte_number] |= rom_byte_mask; } else { searchState.romId[rom_byte_number] &= (uint8_t)~rom_byte_mask; } // increment the byte counter id_bit_number // and shift the mask rom_byte_mask id_bit_number++; rom_byte_mask <<= 1; // if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask if (rom_byte_mask == 0) { crc8 = RomId::calculateCrc8(crc8, searchState.romId[rom_byte_number]); // accumulate the CRC rom_byte_number++; rom_byte_mask = 1; } } } while (rom_byte_number < RomId::byteLen); // loop until through all ROM bytes 0-7 // if the search was successful then if (!((id_bit_number <= (RomId::byteLen * 8)) || (crc8 != 0))) { // search successful so set m_last_discrepancy,m_last_device_flag,search_result searchState.last_discrepancy = last_zero; // check for last device if (searchState.last_discrepancy == 0) { searchState.last_device_flag = true; } search_result = true; } } // if no device found then reset counters so next 'search' will be like a first if (!search_result || (searchState.romId.familyCode() == 0)) { searchState.reset(); search_result = false; } return (search_result ? OneWireMaster::Success : OneWireMaster::OperationFailure); }