Implementation of 1-Wire with added Alarm Search Functionality
Dependents: Max32630_One_Wire_Interface
RomId/RomCommands.cpp
- Committer:
- mfruge
- Date:
- 2019-08-13
- Revision:
- 142:85b71cfd617e
- Parent:
- 139:f0e0a7976846
File content as of revision 142:85b71cfd617e:
/******************************************************************//** * 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 "RomId/RomCommands.h" using namespace OneWire::crc; namespace OneWire { namespace RomCommands { enum OwRomCmd { ReadRomCmd = 0x33, MatchRomCmd = 0x55, SearchRomCmd = 0xF0, SkipRomCmd = 0xCC, ResumeCmd = 0xA5, OverdriveSkipRomCmd = 0x3C, OverdriveMatchRomCmd = 0x69, AlarmSearchCmd = 0xEC }; void SearchState::reset() { last_discrepancy = 0; last_device_flag = false; last_family_discrepancy = 0; romId = RomId(); } void SearchState::findFamily(uint8_t familyCode) { reset(); romId.familyCode() = familyCode; last_discrepancy = 64; } void 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 OWFirst(OneWireMaster & master, SearchState & searchState) { // Reset and begin a new search searchState.reset(); return OWSearch(master, searchState); } OneWireMaster::CmdResult OWNext(OneWireMaster & master, SearchState & searchState) { // Continue the previous search return OWSearch(master, searchState); } OneWireMaster::CmdResult OWVerify(OneWireMaster & master, 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(master, searchState); if (result == OneWireMaster::Success) { // check if same device found if (romId != searchState.romId) { result = OneWireMaster::OperationFailure; } } return result; } OneWireMaster::CmdResult OWReadRom(OneWireMaster & master, RomId & romId) { OneWireMaster::CmdResult result; RomId readId; result = master.OWReset(); if (result == OneWireMaster::Success) { result = master.OWWriteByte(ReadRomCmd); } // read the ROM if (result == OneWireMaster::Success) { result = master.OWReadBlock(readId.buffer.data(), readId.buffer.size()); } // verify CRC8 if (result == OneWireMaster::Success) { if (readId.valid()) { romId = readId; } else { result = OneWireMaster::OperationFailure; } } return result; } OneWireMaster::CmdResult OWSkipRom(OneWireMaster & master) { OneWireMaster::CmdResult result; result = master.OWReset(); if (result == OneWireMaster::Success) { result = master.OWWriteByte(SkipRomCmd); } return result; } OneWireMaster::CmdResult OWMatchRom(OneWireMaster & master, const RomId & romId) { OneWireMaster::CmdResult result; uint8_t buf[1 + RomId::Buffer::csize]; // use MatchROM result = master.OWReset(); if (result == OneWireMaster::Success) { buf[0] = MatchRomCmd; std::memcpy(&buf[1], romId.buffer.data(), romId.buffer.size()); // send command and rom result = master.OWWriteBlock(buf, 1 + romId.buffer.size()); } return result; } OneWireMaster::CmdResult OWOverdriveSkipRom(OneWireMaster & master) { OneWireMaster::CmdResult result = master.OWSetSpeed(OneWireMaster::StandardSpeed); if (result == OneWireMaster::Success) { result = master.OWReset(); } if (result == OneWireMaster::Success) { result = master.OWWriteByte(OverdriveSkipRomCmd); } if (result == OneWireMaster::Success) { result = master.OWSetSpeed(OneWireMaster::OverdriveSpeed); } return result; } OneWireMaster::CmdResult OWOverdriveMatchRom(OneWireMaster & master, const RomId & romId) { OneWireMaster::CmdResult result; // use overdrive MatchROM master.OWSetSpeed(OneWireMaster::StandardSpeed); result = master.OWReset(); if (result == OneWireMaster::Success) { result = master.OWWriteByte(OverdriveMatchRomCmd); if (result == OneWireMaster::Success) { master.OWSetSpeed(OneWireMaster::OverdriveSpeed); // send ROM result = master.OWWriteBlock(romId.buffer.data(), romId.buffer.size()); } } return result; } OneWireMaster::CmdResult OWResume(OneWireMaster & master) { OneWireMaster::CmdResult result; result = master.OWReset(); if (result == OneWireMaster::Success) { result = master.OWWriteByte(ResumeCmd); } return result; } OneWireMaster::CmdResult OWSearch(OneWireMaster & master, SearchState & searchState) { return OWSearchAll(master, searchState, false); } OneWireMaster::CmdResult OWAlarmSearch(OneWireMaster & master, SearchState & searchState) { return OWSearchAll(master, searchState, true); } OneWireMaster::CmdResult OWFirstAlarm(OneWireMaster & master, SearchState & searchState) { searchState.reset(); return OWAlarmSearch(master, searchState); } OneWireMaster::CmdResult OWNextAlarm(OneWireMaster & master, SearchState & searchState) { return OWAlarmSearch(master, searchState); } OneWireMaster::CmdResult OWSearchAll(OneWireMaster & master, SearchState & searchState, bool alarmSearch) { 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 = master.OWReset(); if (result != OneWireMaster::Success) { // reset the search searchState.reset(); return result; } // issue the search command if(alarmSearch){ master.OWWriteByte(AlarmSearchCmd); } else{ master.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.buffer[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 = master.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.buffer[rom_byte_number] |= rom_byte_mask; } else { searchState.romId.buffer[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 = calculateCrc8(crc8, searchState.romId.buffer[rom_byte_number]); // accumulate the CRC rom_byte_number++; rom_byte_mask = 1; } } } while (rom_byte_number < searchState.romId.buffer.size()); // loop until through all ROM bytes 0-7 // if the search was successful then if (!((id_bit_number <= (searchState.romId.buffer.size() * 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); } } }