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CLK/Storage/TimedEventLoop.cpp

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//
// TimedEventLoop.cpp
// Clock Signal
//
// Created by Thomas Harte on 29/07/2016.
// Copyright © 2016 Thomas Harte. All rights reserved.
//
#include "TimedEventLoop.hpp"
#include "../NumberTheory/Factors.hpp"
#include <algorithm>
using namespace Storage;
TimedEventLoop::TimedEventLoop(unsigned int input_clock_rate) :
_input_clock_rate(input_clock_rate) {}
void TimedEventLoop::run_for_cycles(int number_of_cycles)
{
_cycles_until_event -= number_of_cycles;
while(_cycles_until_event <= 0)
{
process_next_event();
}
}
unsigned int TimedEventLoop::get_cycles_until_next_event()
{
return (unsigned int)std::max(_cycles_until_event, 0);
}
void TimedEventLoop::reset_timer()
{
_subcycles_until_event.set_zero();
_cycles_until_event = 0;
}
void TimedEventLoop::reset_timer_to_offset(Time offset)
{
// TODO: apply
}
void TimedEventLoop::jump_to_next_event()
{
reset_timer();
process_next_event();
}
void TimedEventLoop::set_next_event_time_interval(Time interval)
{
// Calculate [interval]*[input clock rate] + [subcycles until this event].
int64_t denominator = (int64_t)interval.clock_rate * (int64_t)_subcycles_until_event.clock_rate;
int64_t numerator =
(int64_t)_subcycles_until_event.clock_rate * (int64_t)_input_clock_rate * (int64_t)interval.length +
(int64_t)interval.clock_rate * (int64_t)_subcycles_until_event.length;
// Simplify now, to prepare for stuffing into possibly 32-bit quantities
int64_t common_divisor = NumberTheory::greatest_common_divisor(numerator % denominator, denominator);
denominator /= common_divisor;
numerator /= common_divisor;
// So this event will fire in the integral number of cycles from now, putting us at the remainder
// number of subcycles
_cycles_until_event = (int)(numerator / denominator);
_subcycles_until_event.length = (unsigned int)(numerator % denominator);
_subcycles_until_event.clock_rate = (unsigned int)denominator;
}
Time TimedEventLoop::get_time_into_next_event()
{
2016-09-18 14:29:45 +00:00
// TODO: calculate, presumably as [length of interval] - ([cycles left] + [subcycles left])
Time zero;
return zero;
}