Sleep and wake timer every 3 minutes

[zuser999]

Hello,

I'm working with a PIC18 and I want to put this PIC into sleep mode and wake it up every 3 minute. How is that possible?
The WDT can put the PIC into sleep only 2.3 seconds.

The IDE I'm working in is MikroC

Thank you

 

[xpress_embedo]

WDT is used to wake your PIC.

Follow this rule:-
Configure watchdog time for the delay required by you
Enable the Watch Dog Timer

Clear Watch Dog Timer
Sleep()
//Controller is in sleep Mode and will wake when watch dog timer overflows

Do it repeatedly

 

[zuser999]

I don't want the PIC to wake up every 2.3 seconds and then put it into sleep. I want the PIC to wake up every 3 minutes and then go to sleep.
As I said in my post, with WDT you can put your PIC into sleep mode for 2.3 sec

 

[wp100]

Hi,

Using the method xpress_embedo suggests only wakes the chip for a couple of nano seconds so it can check/update a 3 min counter and goes back to sleep ; unless the 3 mins has elapsed.

It seems all other methods of waking from sleep requires an external interrupt or possibly Timer1 interrupt if you used a very low speed oscillator - see this thread.
https://www.microchip.com/forums/m596595.aspx