nes-proj/core/sys/clock.h

115 lines
3.5 KiB
C
Raw Normal View History

/** \addtogroup sys
* @{
*/
/**
* \defgroup clock Clock library
*
* The clock library is the interface between Contiki and the platform
* specific clock functionality. The clock library performs a single
* function: measuring time. Additionally, the clock library provides
* a macro, CLOCK_SECOND, which corresponds to one second of system
* time.
*
* \note The clock library need in many cases not be used
* directly. Rather, the \ref timer "timer library" or the \ref etimer
* "event timers" should be used.
*
* \sa \ref timer "Timer library"
* \sa \ref etimer "Event timers"
*
* @{
*/
/*
* Copyright (c) 2004, Swedish Institute of Computer Science.
* 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.
*
* Author: Adam Dunkels <adam@sics.se>
*
* $Id: clock.h,v 1.7 2008/08/15 19:16:09 adamdunkels Exp $
*/
#ifndef __CLOCK_H__
#define __CLOCK_H__
#include "contiki-conf.h"
/**
* Check if a clock time value is less than another clock time value.
*
* This macro checks if a clock time value is less than another clock
* time value. This macro is needed to correctly handle wrap-around of
* clock time values.
*
*/
#define CLOCK_LT(a, b) ((clock_time_t)((a) - (b)) < \
((clock_time_t)(~((clock_time_t)0)) >> 1))
2007-09-07 10:20:30 +00:00
/**
* Initialize the clock library.
*
* This function initializes the clock library and should be called
* from the main() function of the system.
*
*/
void clock_init(void);
/**
* Get the current clock time.
*
* This function returns the current system clock time.
*
* \return The current clock time, measured in system ticks.
*/
CCIF clock_time_t clock_time(void);
void clock_delay(unsigned int);
/**
* A second, measured in system clock time.
*
* \hideinitializer
*/
#ifdef CLOCK_CONF_SECOND
#define CLOCK_SECOND CLOCK_CONF_SECOND
#else
#define CLOCK_SECOND (clock_time_t)32
#endif
int clock_fine_max(void);
unsigned short clock_fine(void);
CCIF unsigned long clock_seconds(void);
#endif /* __CLOCK_H__ */
/** @} */
/** @} */