How to using RTC to wake Arduino up periodically?

Hey guys. I want to make Arduino get in to sleep mode and woke up by the DS1302 periodically. I searched some information about it and found someone said that should use the RTC with alarm function like DS3231. Should i changed the DS1302 to DS3231 ? Can i make the RTC send the high potential periodically ? Thanks for your reply!

Can i make the RTC send the high potential periodically ?

No. Spend a $ for a 3231

One option might be to use the 1Hz output from the RTC connected to an interrupt pin and put the Arduino to sleep between. It will wake for a few ms every second but should be asleep 90+% of the time saving some power. A quick Google finds this that seems to cover the basics. Another option might be this.

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Riva: One option might be to use the 1Hz output from the RTC connected to an interrupt pin and put the Arduino to sleep between. It will wake for a few ms every second but should be asleep 90+% of the time saving some power. A quick Google finds this that seems to cover the basics. Another option might be this.

Thank you very much Riva. I have another question.Can Arduino output the high potential when it during "power down" mode?

fxsh1301: I have another question.Can Arduino output the high potential when it during "power down" mode?

I think the pin states are maintained in all sleep modes.

Riva: One option might be to use the 1Hz output from the RTC connected to an interrupt pin and put the Arduino to sleep between. It will wake for a few ms every second but should be asleep 90+% of the time saving some power. A quick Google finds this that seems to cover the basics. Another option might be this.

The ATmega328P has a Power Save mode that leaves Timer2 on and able to wake the microcontroller. Set Timer2 to CTC mode and an external clock, and use the 1HZ output to feed the Timer input. Enable the overflow interrupt for Timer2 and it will wake the micro up when the timer gets to the value in OCR2A.

Power Save mode usually requires only a few hundred more nanoamps than the full Power Down mode, which will usually make very little difference in your overall battery life.