Prusa-Firmware/Firmware/TimerRemaining.h
2018-06-11 21:19:58 +02:00

40 lines
896 B
C++

/**
* @file
* @author Marek Bel
*/
#ifndef TIMERREMAINING_H
#define TIMERREMAINING_H
#include "Timer.h"
#include "Arduino.h"
#include <limits.h>
class TimerRemaining : public LongTimer
{
public:
/**
* @brief Time remaining to expiration
*
* @param msPeriod timer period in milliseconds
* @return time remaining to expiration in milliseconds
* @retval 0 Timer has expired, or was not even started.
*/
unsigned long remaining(unsigned long msPeriod)
{
if (!m_isRunning) return 0;
if (expired(msPeriod)) return 0;
const unsigned long now = millis();
if ((m_started <= m_started + msPeriod) || (now < m_started))
{
return (m_started + msPeriod - now);
}
else //(now >= m_started)
{
return ULONG_MAX - now + (m_started + msPeriod);
}
}
};
#endif // ifndef TIMERREMAINING_H