time_t __time32( time_t * timer )
{
time_t t;
/* Add the time offset */
t = rtcStartTime;
/* Add time based on number of counter overflows*/
t += rtcOverflowCounter * overflow_interval;
/* Correct if overflow interval is not an integer*/
if ( overflow_interval_r != 0 )
{
t += rtcOverflowCounter * overflow_interval_r / COUNTS_PER_SEC;
}
/* Add the number of seconds for BURTC */
t += (BURTC_CounterGet() / COUNTS_PER_SEC);
/* Copy system time to timer if not NULL*/
if ( !timer )
{
timer = &t;
}
return t;
}
/**************************************************************************//**
* @brief vPortSetupTimerInterrupt
* Override the default definition of vPortSuppressTicksAndSleep() that is weakly
* defined in the FreeRTOS Cortex-M3 port layer layer
*****************************************************************************/
void vPortSuppressTicksAndSleep(portTickType xExpectedIdleTime)
{
unsigned long ulReloadValue, ulCompleteTickPeriods;
portTickType xModifiableIdleTime;
/* Make sure the SysTick reload value does not overflow the counter. */
if (xExpectedIdleTime > xMaximumPossibleSuppressedTicks)
{
xExpectedIdleTime = xMaximumPossibleSuppressedTicks;
}
/* Calculate the reload value required to wait xExpectedIdleTime
* tick periods. -1 is used because this code will execute part way
* through one of the tick periods, and the fraction of a tick period is
* accounted for later. */
ulReloadValue = (ulTimerReloadValueForOneTick * (xExpectedIdleTime ));
if (ulReloadValue > ulStoppedTimerCompensation)
{
ulReloadValue -= ulStoppedTimerCompensation;
}
/* Stop the SysTick momentarily. The time the SysTick is stopped for
* is accounted for as best it can be, but using the tickless mode will
* inevitably result in some tiny drift of the time maintained by the
* kernel with respect to calendar time. */
/* Stop the RTC clock*/
BURTC_Enable(false);
/* Enter a critical section but don't use the taskENTER_CRITICAL()
* method as that will mask interrupts that should exit sleep mode. */
INT_Disable();
/* The tick flag is set to false before sleeping. If it is true when sleep
* mode is exited then sleep mode was probably exited because the tick was
* suppressed for the entire xExpectedIdleTime period. */
intTickFlag = false;
/* If a context switch is pending or a task is waiting for the scheduler
* to be unsuspended then abandon the low power entry. */
if (eTaskConfirmSleepModeStatus() == eAbortSleep)
{
BURTC_Enable(true);
/* Re-enable interrupts */
INT_Enable();
}
else
{
/* Set the new reload value. */
ulReloadValue -= BURTC_CounterGet();
BURTC_CompareSet(0, ulReloadValue);
/* Restart the counter*/
BURTC_CounterReset();
/* Sleep until something happens. configPRE_SLEEP_PROCESSING() can
* set its parameter to 0 to indicate that its implementation contains
* its own wait for interrupt or wait for event instruction, and so wfi
* should not be executed again. However, the original expected idle
* time variable must remain unmodified, so a copy is taken. */
xModifiableIdleTime = xExpectedIdleTime;
configPRE_SLEEP_PROCESSING(xModifiableIdleTime);
if (xModifiableIdleTime > 0)
{
SLEEP_Sleep();
__DSB();
__ISB();
}
configPOST_SLEEP_PROCESSING(xExpectedIdleTime);
/* Stop SysTick. Again, the time the SysTick is stopped for is
* accounted for as best it can be, but using the tickless mode will
* inevitably result in some tiny drift of the time maintained by the
* kernel with respect to calendar time. */
BURTC_Enable(false);
/* Re-enable interrupts - see comments above __disable_interrupt()
* call above. */
INT_Enable();
if (intTickFlag != false)
{
/* The tick interrupt has already executed,
* Reset the alarm value with whatever remains of this tick period. */
BURTC_CompareSet(0, TIMER_CAPACITY & (ulTimerReloadValueForOneTick - BURTC_CounterGet()));
/* The tick interrupt handler will already have pended the tick
* processing in the kernel. As the pending tick will be
* processed as soon as this function exits, the tick value
* maintained by the tick is stepped forward by one less than the
* time spent waiting. */
ulCompleteTickPeriods = xExpectedIdleTime - 1UL;
}
else
{
/* Some other interrupt than system tick ended the sleep.
* Calculate how many tick periods passed while the processor
* was waiting */
ulCompleteTickPeriods = BURTC_CounterGet() / ulTimerReloadValueForOneTick;
/* The reload value is set to whatever fraction of a single tick
* period remains. */
if (ulCompleteTickPeriods == 0)
{
ulReloadValue = ulTimerReloadValueForOneTick - BURTC_CounterGet();
}
else
{
ulReloadValue = BURTC_CounterGet() - (ulCompleteTickPeriods * ulTimerReloadValueForOneTick);
}
BURTC_CompareSet(0, ulReloadValue);
}
/* Restart the RTCounter*/
BURTC_CounterReset();
/* The tick forward by the number of tick periods that
* remained in a low power state. */
vTaskStepTick(ulCompleteTickPeriods);
}
}
