Colony

#include "time.h"

/**

 * Copyright (c) 2007 Colony Project

 * 

 * 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.

 **/

/**

 * @file time.c

 * @brief Timer code

 *

 * Implementation of functions for timers.

 *

 * @author Colony Project, CMU Robotics Club

 **/

/*

time.c

anything that requires a delay

mostly delay_ms

author: Robotics Club, Colony Project

Change Log:

	4.7.08 - Austin

		Modified for bay boards

	2.5.07 - Kevin

		Aaron fixed the orb/servo code and made them use timer3 but compare registers B and C. He hard set the prescaler

		to 8 so the RTC broke. Changed it so that we use a 8 prescaler which sets the compare match at 1/16th of a second.

		You now count how many 16ths of a second you want until you trigger your actual interrupt. Works. Changed defines

		for time so you can still call rtc_init with a scale but now it is defined in terms of actual time like second, quarter_second

		etc. Read that section in the time.h file for more information. Tested and works, though the clock drifts more than

		it used to

	1.30.07 - Kevin

		Modified the clock to run on timer3 on the Dragonfly. Works with decent accuracy. Using a prescaler of 256

	the timer counts up to a precomputer value which will trigger an interrupt and reset the timer. Multiples of

	256 change it by that multiple. Refer to the time.h file for all possible prescalers.

		The interrupt will call a specified function _rtc_func every pulse.

		All of it has been tested and it works.

*/

#include <avr/interrupt.h>

#include <util/delay.h>

#include <time.h>

#include <serial.h>

static volatile int _rtc_val = 0;

static volatile int _rtc_pulse = 0;

static volatile int _rtc_scale = 32;	//Defaults to 1 Second per pulse

static void (*_rtc_f)(void) = 0;

/**

 * @defgroup time Time

 * @brief Time functions

 * 

 * Functions dealing with time.

 * 

 * @{

 **/

/**

 * Delays for the specified number of milliseconds.

 * The accuracy of this function is unknown.

 *

 * @param ms the number of milliseconds to delay for

 **/

void delay_ms(int ms) 

{

	for(; ms > 15; ms-=15)

		_delay_ms(15);

	_delay_ms(ms);

}

/* 	Prescales defined in time.h. SECOND will give you 1 second.

	More scales are defined in the time.h file.

	rtc_func is the address to a function that you want called every clock tick. */

/**

 * Initializes the real time clock. Prescales are defined in time.h.

 * For example, SECOND will give 1 second. The specified function is

 * called every clock tick. For the real time clock to activate,

 * interrupts must be enabled. (through sei() )

 *

 * @param prescale_opt the period with which the timer is triggered

 * @param rtc_func the function called when the timer is triggered

 *

 * @see rtc_get, rtc_reset

 *

 **/

void rtc_init(int prescale_opt, void (*rtc_func)(void)) {

	/* 	Interrupt on match to ICR1 */

	TIMSK1 |= _BV(ICIE1);

	/*	Store the pointer to the function to be used in the interrupt */

	_rtc_f = rtc_func;

	/*	Store how many 1/16ths of a second you want to let by before triggering an interrupt */

	_rtc_scale = prescale_opt;

}

/**

 * Returns the time elapsed in seconds since the last call to

 * rtc_init or rtc_reset.

 *

 * @return the number of seconds since the last call to rtc_init or rtc_reset

 *

 * @see rtc_init, rtc_reset

 **/

int rtc_get(void){

	return _rtc_val;

}

/**

 * Resets the real time clock counter to 0.

 *

 * @see rtc_init, rtc_get

 **/

void rtc_reset(void){

	_rtc_val = 0;

}

/** @} **/ //end defgroup

/*	Called every pulse. Function in _rtc_f is called every _rtc_scale and also the counter is updated.

	Bascially, since the pulse is hard set at 1/16s  you want to count how many 16ths of a second have passed

	and when it reaches the amount of time you want, execute the code. */

ISR(TIMER1_CAPT_vect) {

	if (_rtc_pulse ==  _rtc_scale) {

		//Increment the real time clock counter

		_rtc_val++;

		//Calls the function tied to the real time clock if defined

		if(_rtc_f != 0)

			_rtc_f();

		//Resets the pulse until the next scale is matched

		_rtc_pulse = 0;

	}	

	//Updates the amount of pulses seen since the last scale match

	_rtc_pulse++;

}

/**

 * Copyright (c) 2007 Colony Project

 * 

 * 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.

 **/

/**

 * @file time.h

 * @brief Contains time-related functions and definitions

 *

 * Contains functions and definitions for dealing with time,

 * namely delay_ms and the realtime clock.

 *

 * @author Colony Project, CMU Robotics Club

 **/

#ifndef _TIME_H_

#define _TIME_H_

/*	Predefined times for prescale_opt in time.c.

	To make you own, know that a pulse is 1/16th of a second. You cannot get less than this. To get more, you need

	to know how many 16ths of a second are in the time you want. (Time_desired * 16 = prescaler_opt)

*/

/**

 * @addtogroup time

 * @{

 **/

/** @brief A sixteenth of a second **/

#define SIXTEENTH_SECOND 14

/** @brief An eighth of a second **/

#define EIGTH_SECOND 28

/** @brief A quarter of a second **/

#define QUARTER_SECOND 55

/** @brief Half of a second **/

#define HALF_SECOND	110

/** @brief One second **/

#define SECOND 220

/** @brief Two seconds **/

#define TWO_SECOND 440

/** @brief Four seconds **/

#define FOUR_SECOND 880

/** @brief Delay execution for the specified time **/

void delay_ms(int ms) ;

/** @brief Enable the realtime clock **/

void rtc_init(int prescale_opt, void (*rtc_func)(void));

/** @brief Reset the counter of the realtime clock **/

void rtc_reset(void);

/** @brief Get the value of the realtime clock. **/

int rtc_get(void);

/** @} **/

#endif