/* * Copyright (C) 2014 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. */ #ifndef __I2C_PP_H__ #define __I2C_PP_H__ #include #include "ch.h" #include "hal.h" struct I2CClockConfig { float clock_source_f; float bus_f; float high_period_ns; static constexpr float period_ns(const float f) { return 1e9 / f; } constexpr uint32_t i2c_period_count() const { return period_ns(bus_f) / period_ns(clock_source_f) + 0.5f; } constexpr uint32_t i2c_high_count() const { return high_period_ns / period_ns(clock_source_f) + 0.5f; } constexpr uint32_t i2c_low_count() const { return i2c_period_count() - i2c_high_count(); } }; class I2C { public: using address_t = uint8_t; constexpr I2C(I2CDriver* const driver) : _driver(driver) { } void start(const I2CConfig& config); void stop(); bool probe(i2caddr_t addr, systime_t timeout = TIME_INFINITE); bool receive( const address_t slave_address, uint8_t* const data, const size_t count, const systime_t timeout = TIME_INFINITE); bool transmit( const address_t slave_address, const uint8_t* const data, const size_t count, const systime_t timeout = TIME_INFINITE); private: I2CDriver* const _driver; bool transfer( const address_t slave_address, const uint8_t* const data_tx, const size_t count_tx, uint8_t* const data_rx, const size_t count_rx, const systime_t timeout); }; #endif /*__I2C_PP_H__*/