I decided to use an external clock (RTC) in order to wake up my Pro-Mini every minute or hour depending on the application.
I am a bit disappointed to still need ~7mA when in sleep mode. Added to that are the 3mA of the RTC, but that's another problem.
7mA includes the power LED on the Mini, which I have not yet removed (I wish I did not have to, not sure how much i'd save...)
Power supply is 4 x AA batteries ~(~6V) directly to any of the Mini's VCC.
My question is:
Is there a 'deeper' sleep mode than the one I am using below?
I am using:
#include <DS3232RTC.h>
#include <TimeLib.h>
#include <avr/sleep.h>
and:
attach_RTC_interupt(); delay(100);
set_sleep_mode(SLEEP_MODE_PWR_DOWN);
sleep_enable();
sleep_mode(); // here the CPu is actually put to sleep. The program continues from here after waking up
sleep_disable(); // first thing after waking from sleep: disable sleep.
detach_RTC_interupt();
Regards,
Pascal.