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arduino-libraries / RTCZero

RTC Library for SAMD21 based boards
http://arduino.cc/en/Reference/RTC
GNU Lesser General Public License v2.1
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Crystal-less implementation time issue #50

Closed ubidefeo closed 5 years ago

ubidefeo commented 5 years ago

I have used this code to successfully set the device to sleep and wake up after 20 seconds, but on the Nano 33 IoT it won't work and I guess it's due to how seconds are turned into ticks and the fact that it doesn't tick at 32KHz. Just guessing :) Works on MKR Zero, MKR WiFi 1010 and MKR GSM 1400

RTCZero realTimeClock;

void enterSleep(){
  realTimeClock.begin();
  uint32_t rtcEpoch = realTimeClock.getEpoch();
  realTimeClock.setAlarmEpoch(rtcEpoch + 20);
  realTimeClock.enableAlarm(realTimeClock.MATCH_HHMMSS);

  realTimeClock.attachInterrupt(ISR);
  realTimeClock.standbyMode();
}

void ISR(){
  playWakeUpSequence = true;
  realTimeClock.disableAlarm();
  realTimeClock.setTime(hours, minutes, seconds);
}
pnndra commented 5 years ago

Hi. Since we don't have a 32khz crystal rtc can't be used on this board

ubidefeo commented 5 years ago

Ran a test not dependant on Serial output by blinking the onboard LED 3 times at wakeup and it indeed worked. So it might just be a case of bus stall as referenced in #44 . I'll close this one but maybe someone can take a look if it's the case to merge that PR :)