/* * Author: Brendan Le Foll * Copyright (c) 2014 Intel Corporation. * * 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 THE AUTHORS OR COPYRIGHT HOLDERS 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. */ #pragma once #include "i2c.h" #include "types.hpp" #include namespace mraa { /** * @brief API to Inter-Integrated Circuit * * An I2c object represents an i2c master and can talk multiple i2c slaves by * selecting the correct address * @htmlinclude i2c.txt * * @snippet I2c-compass.cpp Interesting */ class I2c { public: /** * Instantiates an i2c bus. Multiple instances of the same bus can * exist and the bus is not guarranteed to be on the correct address * before read/write. * * @param bus The i2c bus to use * @param raw Whether to disable pinmapper for your board */ I2c(int bus, bool raw = false) { if (raw) { m_i2c = mraa_i2c_init_raw(bus); } else { m_i2c = mraa_i2c_init(bus); } if (m_i2c == NULL) { throw std::invalid_argument("Invalid i2c bus"); } } /** * Closes the I2c Bus used. This does not guarrantee the bus will not * be usable by anyone else or communicates this disconnect to any * slaves. */ ~I2c() { mraa_i2c_stop(m_i2c); } /** * Sets the i2c Frequency for communication. Your board may not support * the set frequency. Anyone can change this at any time and this will * affect every slave on the bus * * @param mode Frequency to set the bus to * @return Result of operation */ Result frequency(I2cMode mode) { return (Result) mraa_i2c_frequency(m_i2c, (mraa_i2c_mode_t) mode); } /** * Set the slave to talk to, typically called before every read/write * operation * * @param address Communicate to the i2c slave on this address * @return Result of operation */ Result address(uint8_t address) { return (Result) mraa_i2c_address(m_i2c, address); } /** * Read exactly one byte from the bus * * @return char read from the bus */ uint8_t readByte() { return (uint8_t) mraa_i2c_read_byte(m_i2c); } /** * Read length bytes from the bus into *data pointer * * @param data Data to read into * @param length Size of read in bytes to make * @return length of read, should match length */ int read(uint8_t* data, int length) { return mraa_i2c_read(m_i2c, data, length); } /** * Read byte from an i2c register * * @param reg Register to read from * @return char read from register */ uint8_t readReg(uint8_t reg) { return mraa_i2c_read_byte_data(m_i2c, reg); } /** * Read word from an i2c register * * @param reg Register to read from * @return char read from register */ uint16_t readWordReg(uint8_t reg) { return mraa_i2c_read_word_data(m_i2c, reg); } /** * Read length bytes from the bus into *data pointer starting from * an i2c register * * @param reg Register to read from * @param data pointer to the byte array to read data in to * @param length max number of bytes to read * @return length passed to the function or -1 */ int readBytesReg(uint8_t reg, uint8_t* data, int length) { return mraa_i2c_read_bytes_data(m_i2c, reg, data, length); } /** * Write a byte on the bus * * @param data The byte to send on the bus * @return Result of operation */ Result writeByte(uint8_t data) { return (Result) mraa_i2c_write_byte(m_i2c, data); } /** * Write length bytes to the bus, the first byte in the array is the * command/register to write * * @param data Buffer to send on the bus, first byte is i2c command * @param length Size of buffer to send * @return Result of operation */ Result write(const uint8_t* data, int length) { return (Result) mraa_i2c_write(m_i2c, data, length); } /** * Write a byte to an i2c register * * @param reg Register to write to * @param data Value to write to register * @return Result of operation */ Result writeReg(uint8_t reg, uint8_t data) { return (Result) mraa_i2c_write_byte_data(m_i2c, data, reg); } /** * Write a word to an i2c register * * @param reg Register to write to * @param data Value to write to register * @return Result of operation */ Result writeWordReg(uint8_t reg, uint16_t data) { return (Result) mraa_i2c_write_word_data(m_i2c, data, reg); } private: mraa_i2c_context m_i2c; }; }