void vPortSetupTimerInterrupt( void )
{
/* Configure the RTCC to generate the RTOS tick interrupt. */
/* The maximum number of ticks that can be suppressed depends on the clock
frequency. */
xMaximumPossibleSuppressedTicks = ULONG_MAX / ulReloadValueForOneTick;
/* Ensure LE modules are accessible. */
CMU_ClockEnable( cmuClock_CORELE, true );
/* Use LFXO. */
CMU_ClockSelectSet( cmuClock_LFE, cmuSelect_LFXO );
/* Enable clock to the RTC module. */
CMU_ClockEnable( cmuClock_RTCC, true );
/* Use channel 1 to generate the RTOS tick interrupt. */
RTCC_ChannelCCVSet( lpRTCC_CHANNEL, ulReloadValueForOneTick );
RTCC_Init( &xRTCInitStruct );
RTCC_ChannelInit( lpRTCC_CHANNEL, &xRTCCChannel1InitStruct );
RTCC_EM4WakeupEnable( true );
/* Disable RTCC interrupt. */
RTCC_IntDisable( _RTCC_IF_MASK );
RTCC_IntClear( _RTCC_IF_MASK );
RTCC->CNT = _RTCC_CNT_RESETVALUE;
/* The tick interrupt must be set to the lowest priority possible. */
NVIC_SetPriority( RTCC_IRQn, configLIBRARY_LOWEST_INTERRUPT_PRIORITY );
NVIC_ClearPendingIRQ( RTCC_IRQn );
NVIC_EnableIRQ( RTCC_IRQn );
RTCC_IntEnable( RTCC_IEN_CC1 );
RTCC_Enable( true );
#if( lpUSE_TEST_TIMER == 1 )
{
void prvSetupTestTimer( void );
/* A second timer is used to test the path where the MCU is brought out
of a low power state by a timer other than the tick timer. */
prvSetupTestTimer();
}
#endif
}
void lp_ticker_set_interrupt(timestamp_t timestamp)
{
uint64_t timestamp_ticks;
uint64_t current_ticks = RTCC_CounterGet();
timestamp_t current_time = ((uint64_t)(current_ticks * 1000000) / (LOW_ENERGY_CLOCK_FREQUENCY / RTC_CLOCKDIV_INT));
/* Initialize RTC */
lp_ticker_init();
/* calculate offset value */
timestamp_t offset = timestamp - current_time;
if(offset > 0xEFFFFFFF) offset = 100;
/* map offset to RTC value */
// ticks = offset * RTC frequency div 1000000
timestamp_ticks = ((uint64_t)offset * (LOW_ENERGY_CLOCK_FREQUENCY / RTC_CLOCKDIV_INT)) / 1000000;
// checking the rounding. If timeout is wanted between RTCC ticks, irq should be configured to
// trigger in the latter RTCC-tick. Otherwise ticker-api fails to send timer event to its client
if(((timestamp_ticks * 1000000) / (LOW_ENERGY_CLOCK_FREQUENCY / RTC_CLOCKDIV_INT)) < offset){
timestamp_ticks++;
}
timestamp_ticks += current_ticks;
/* RTCC has 32 bit resolution */
timestamp_ticks &= 0xFFFFFFFF;
/* check for RTCC limitation */
if((timestamp_ticks - RTCC_CounterGet()) >= 0x80000000) timestamp_ticks = RTCC_CounterGet() + 2;
/* init channel */
RTCC_CCChConf_TypeDef ccchConf = RTCC_CH_INIT_COMPARE_DEFAULT;
RTCC_ChannelInit(0,&ccchConf);
/* Set callback */
RTCC_ChannelCCVSet(0, (uint32_t)timestamp_ticks);
RTCC_IntEnable(RTCC_IF_CC0);
}
int rtc_set_alarm(struct tm *time, rtc_alarm_cb_t cb, void *arg)
{
rtc_state.alarm_cb = cb;
rtc_state.alarm_arg = arg;
rtc_state.alarm_year = time->tm_year;
/* disable interrupt so it doesn't accidentally trigger */
RTCC_IntDisable(RTCC_IEN_CC0);
/* set compare registers */
RTCC_ChannelDateSet(0,
RTCC_Channel_Month2BCD(time->tm_mon) |
RTCC_Channel_Day2BCD(time->tm_mday));
RTCC_ChannelTimeSet(0,
RTCC_Channel_Hour2BCD(time->tm_hour) |
RTCC_Channel_Minute2BCD(time->tm_min) |
RTCC_Channel_Second2BCD(time->tm_sec));
/* enable the interrupt */
RTCC_IntClear(RTCC_IFC_CC0);
RTCC_IntEnable(RTCC_IEN_CC0);
return 0;
}
