ESP8266 Community Forum

This is interesting topic. I was first planning to use my DS1307 to wakeup esp8266, but then found this:
http://forum.arduino.cc/index.php?topic=137067.0

I think DS1337 would be better:
http://timewitharduino.blogspot.fi/2010 ... s1337.html
http://forum.arduino.cc/index.php?topic=20937.0
http://electronics.stackexchange.com/qu ... ds1337-rtc

I have ordered the DS1337 now.

Here is an other interesting link to a project where they used the DS1337 in combination with mosfet AO3401 to turn on a sensor. I'm hoping it would work with the esp8266 as well.

http://letsmakerobots.com/node/34872
http://letsmakerobots.com/node/33532

i am following your results

Sleepy Head wrote:well i think the context here is saving battery power so the sensor can run for weeks.
Waking the esp8266 every half hour just to go to sleep again is going to consume too much power.

I'm reading up on RTC modules now. They can run a long time with battery backup.

Assuming the chip draws 20mA with wifi functionality turned off, and it needs 600ms for the startup and go to sleep again:
http://www.wolframalpha.com/input/?i=20 ... eek+in+mAh
You lose 1mAh of charge per week.

Does not seem worth to add an external timer for that..
Instead I would modify the lua sleep() method, so that a sleep check is performed in C before the lua machine starts.
That should significantly reduce the time the chip is actually on.