/* * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc. * * This file is part of PortaPack. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 51 Franklin Street, * Boston, MA 02110-1301, USA. */ #include "tpms_packet.hpp" #include "crc.hpp" namespace tpms { Timestamp Packet::received_at() const { return packet_.timestamp(); } ManchesterFormatted Packet::symbols_formatted() const { return format_manchester(decoder_); } Optional Packet::reading(const SignalType signal_type) const { if( signal_type == SignalType::FLM ) { const auto length = crc_valid_length(); switch(length) { case 64: return Reading { Reading::Type::FLM_64, reader_.read(0, 32), Pressure { static_cast(reader_.read(32, 8)) * 4 / 3 }, Temperature { static_cast(reader_.read(40, 8) & 0x7f) - 50 } }; case 72: return Reading { Reading::Type::FLM_72, reader_.read(0, 32), Pressure { static_cast(reader_.read(40, 8)) * 4 / 3 }, Temperature { static_cast(reader_.read(48, 8)) - 50 } }; case 80: return Reading { Reading::Type::FLM_80, reader_.read(8, 32), Pressure { static_cast(reader_.read(48, 8)) * 4 / 3 }, Temperature { static_cast(reader_.read(56, 8)) - 50 } }; default: return { }; } } if( signal_type == SignalType::Schrader ) { const auto flags = reader_.read(0, 3); const auto checksum = reader_.read(35, 2); return Reading { Reading::Type::Schrader, reader_.read(3, 24), Pressure { static_cast(reader_.read(27, 8)) } }; } if( signal_type == SignalType::GMC ) { return Reading { Reading::Type::GMC_96, reader_.read(20, 32), Pressure { static_cast(reader_.read(52, 8)) } }; } return { }; } size_t Packet::crc_valid_length() const { constexpr uint32_t checksum_bytes = 0b1111111; constexpr uint32_t crc_72_bytes = 0b111111111; constexpr uint32_t crc_80_bytes = 0b1111111110; std::array bytes; for(size_t i=0; i crc_72 { 0x01, 0x00 }; CRC<8> crc_80 { 0x01, 0x00 }; for(size_t i=0; i