mhz16.hpp

/*
 * Author: Jon Trulson <jtrulson@ics.com>
 * Copyright (c) 2015 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 <string>
#include <iostream>

#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <termios.h>
#include <sys/time.h>
#include <sys/select.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <mraa/uart.h>

const int MHZ16_DEFAULT_UART = 0;

// protocol start and end codes
const uint8_t MHZ16_START = 0x7e;
const uint8_t MHZ16_END   = 0x7e;

namespace upm {
  class MHZ16 {
  public:


    MHZ16(int uart);

    ~MHZ16();

    bool dataAvailable(unsigned int millis);

    int readData(char *buffer, int len);

    int writeData(char *buffer, int len);

    bool setupTty(speed_t baud=B9600);

    bool verifyPacket(uint8_t *pkt, int len);

    bool getData();

    int getGas();

    int getTemperature();

    void calibrateZeroPoint();

  protected:
    int ttyFd() { return m_ttyFd; };

  private:
    mraa_uart_context m_uart;
    int m_ttyFd;
    int gas;
    int temp;
  };
}