Long sleep with Interrupts.

Projects Programming
1

Hi I have been playing with Interrupts and sleep but I am stuck on sleeping for longer than 1 second based on timers.

Using timer 1 on the micro pro. I can with Timer 2 get a 1Hz interrupt. And am also using pins 2 and 3 as standard hardware Intrrupts.

What I want is for the Arduino to sleep for about 1 minute, it does not have to been millisecond accurate. It to measure temp of pond every X minutes and record the data.

How can I sleep for X number of seconds / minutes. Looking at the prescalers on the timers timer 1 with its 16bit registrar and prescaler of ,1024 gives a max of 1Hz

I am sure I am missing a simply way to do this, but is there a way to get a longer timer interval than 1Hz to use as intrupt?

Thank you.

Aaron

2

I know I could do this by passing number of milliseconds to sleep for.

But my thought is to simply always be in sleep, and use intrupts to fire if code before dropping back to sleep.

So it never wakes up unless woken, rather than "sleep for X minutes" I want to say sleep untill woken"

And then be able to start a timer at any point after putting it to sleep to then run a job in X number of seconds.

3

Because the processor can wake up and go back to sleep very quickly, if your goal is power saving, you can just wake up every second, increment a counter, and go back to sleep if your system sleep interval is not expired.