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Topic: Energy saving question and RTC DS3234 Alarms (Read 1 time) previous topic - next topic

xload

Feb 01, 2013, 02:10 am Last Edit: Feb 02, 2013, 07:39 pm by xload Reason: 1
Hello I need to wake up the arduino every 10 or 15 minutes, I have the DS3234 RTC, but I don't understand how set the alarm,somebody can help me?

Best regards.

Quick5pnt0

Try searching google for the timealarm library.

UKHeliBob

When you say "wake up the arduino" what state is it in at the time and how does it get in that state ?
Please do not send me PMs asking for help.  Post in the forum then everyone will benefit from seeing the questions and answers.

xload

Hello, a lot of thanks to all, the problem in the time alarm library is that the arduino is always on, I need that the arduino go to sleep and wake up each 15 minutes to save battery, I think that the DS3234 RTC have internal alarms to do this, but I don't understand how to set up to activate each 15 minutes.

el_supremo

I don't think you can make the DS3234 alarm every 15 minutes. You would have to set an alarm to go off every minute and then, when the alarm does go off, read the minutes register to see if it is 0, 15 , 30 or 45.

Pete

xload


I don't think you can make the DS3234 alarm every 15 minutes. You would have to set an alarm to go off every minute and then, when the alarm does go off, read the minutes register to see if it is 0, 15 , 30 or 45.

Pete


A lot of thanks Pete, do you know if there is any RTC that I can program to wake up the arduino each 15 minutes? I really need save battery.

Best regards.

PaulS

Quote
I really need save battery.

How much battery are you going to save by not waking up, seeing that the time is not right, and going back to sleep. Those few milli-micro-amps aren't going to matter all that much.

robtillaart

#7
Feb 02, 2013, 07:07 pm Last Edit: Feb 02, 2013, 07:09 pm by robtillaart Reason: 1
The best description I know about sleep modes of Arduino is here - http://www.gammon.com.au/forum/?id=11497 -

Better change the title of your thread to "Sleep mode (how)" or "energy saving mode question" because that is the question.

The current title reflect a solution (or not ;)

Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

robtillaart


search for different sleep modes on the page mentioned
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

el_supremo

I've used the DS3231 (I2C similar to DS3234) to wake up every minute and do a task once every ten minutes. The time spent awake when not performing a task is negligible.

Pete

xload

#10
Feb 02, 2013, 07:29 pm Last Edit: Feb 02, 2013, 07:31 pm by xload Reason: 1
Hello, the problem is not how to sleep the arduino, the problem is how to wake up each 10 or 15 minutes,if there is not another way i will try the el_supremo solution, waking up each minute :(

robtillaart

Some sleep modes keep the timers active,
These timers can be programmed to trigger an ISR.
This ISR can wake the system when appropriate

Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

xload


Some sleep modes keep the timers active,
These timers can be programmed to trigger an ISR.
This ISR can wake the system when appropriate



Hello robtillaart, do you have an example? I don't found it.

robtillaart

That info Is on the same page - http://www.gammon.com.au/forum/?id=11497 - search for "Waking from sleep with a timer"
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

xload


That info Is on the same page - http://www.gammon.com.au/forum/?id=11497 - search for "Waking from sleep with a timer"


Hello robtillaart, I understand that in the example the arduino is waking up each 8 seconds, the maximum that you can set up a watchdog, but I need wake up each 10 or 15 minutes, how can I do this?

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