nuttx-apps/examples/obd2/obd2_main.c

/****************************************************************************
 * examples/obd2/obd2_main.c
 *
 *   Copyright (C) 2017 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>
#include <stdio.h>

#include "canutils/obd.h"
#include "canutils/obd_pid.h"
#include "canutils/obd_frame.h"

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * obd2_main
 ****************************************************************************/

#ifdef BUILD_MODULE
int main(int argc, FAR char *argv[])
#else
int obd2_main(int argc, char *argv[])
#endif
{
  struct obd_dev_s *dev;
  int ret;

  dev = obd_init("/dev/can0", 0, 0);
  if (!dev)
    {
      printf("Failed to initialize the OBD-II device!\n");
      return -1;
    }

  /* Request the RPM */

  ret = obd_send_request(dev, OBD_SHOW_DATA, OBD_PID_RPM);
  if (ret < 0)
    {
      printf("Failed to request RPM!\n");
      return -1;
    }

  /* Wait for response */

  ret = obd_wait_response(dev, OBD_SHOW_DATA, OBD_PID_RPM, 100);
  if (ret < 0)
    {
      printf("Failed to receive the response!\n");
      return -1;
    }

  /* Decode the received PID */

  printf("RPM = %s\n", obd_decode_pid(dev, OBD_PID_RPM));

  return 0;
}