nes-proj/os/net/mac/tsch/tsch-adaptive-timesync.h
2018-04-28 13:02:11 -07:00

77 lines
2.8 KiB
C

/*
* Copyright (c) 2015, SICS Swedish ICT.
* All rights reserved.
*
* 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 of the Institute 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 INSTITUTE 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 INSTITUTE 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.
*
* This file is part of the Contiki operating system.
*
*/
/**
* \addtogroup tsch
* @{
* \file
* TSCH adaptive time synchronization
*/
#ifndef __TSCH_ADAPTIVE_TIMESYNC_H__
#define __TSCH_ADAPTIVE_TIMESYNC_H__
/********** Includes **********/
#include "contiki.h"
/***** External Variables *****/
/** \brief The neighbor last used as our time source */
extern struct tsch_neighbor *last_timesource_neighbor;
/********** Functions *********/
/**
* \brief Updates timesync information for a given neighbor
* \param n The neighbor
* \param time_delta_asn ASN time delta since last synchronization, i.e. number of slots elapsed
* \param drift_correction The measured drift in ticks since last synchronization
*/
void tsch_timesync_update(struct tsch_neighbor *n, uint16_t time_delta_asn, int32_t drift_correction);
/**
* \brief Computes time compensation for a given point in the future
* \param delta_ticks The number of ticks in the future we want to calculate compensation for
* \return The time compensation
*/
int32_t tsch_timesync_adaptive_compensate(rtimer_clock_t delta_ticks);
/**
* \brief Gives the estimated clock drift w.r.t. the time source in PPM (parts per million)
* \return The time drift in PPM
*/
long int tsch_adaptive_timesync_get_drift_ppm(void);
#endif /* __TSCH_ADAPTIVE_TIMESYNC_H__ */
/** @} */