danYour plan to use a Ds3231 chip and have the Pi shutdown automatically sounds good.
I don't know of any other way to keep accurate time on the Raspi.
The RTC information I sent you a link for in an earlier post is old and I have been working on new instructions for using an RTC with the newest raspbian versions (Jessie or Stretch).
I don't know your location or what access you have to electronic components but there is a nice RTC that is designed specifically for the Pi from Adafruit:
https://www.adafruit.com/product/3386
You just need to get it with the battery and plug it on to the Pi's GPIO pins (pins 1 to 6). It will work with the relay_16 SIP plugin.
I will post here as soon as I have the new instructions ready.
Dan
Many thanks for your replay
here are some updates
i have tried to buy Ds3231 from local reseller at the beginning they said it is available but when i get there they said they only have DS1302 witch is different chip ! although i have tried hardly to hooked up and make it work with My rpi but no luck . then i ordered the one that you recommend but it will take about Five weeks to deliver "i live in 3rd world country
"
until then i have decided to do the following :
as soon as i have deployed everything i will post the entire project diagrams and pictures in desired forum
many thanks again for this nice community Dan
Shad
I don't know of any other way to keep accurate time on the Raspi.
The RTC information I sent you a link for in an earlier post is old and I have been working on new instructions for using an RTC with the newest raspbian versions (Jessie or Stretch).
I don't know your location or what access you have to electronic components but there is a nice RTC that is designed specifically for the Pi from Adafruit:
https://www.adafruit.com/product/3386
You just need to get it with the battery and plug it on to the Pi's GPIO pins (pins 1 to 6). It will work with the relay_16 SIP plugin.
I will post here as soon as I have the new instructions ready.
Dan
Many thanks for your replay
here are some updates
i have tried to buy Ds3231 from local reseller at the beginning they said it is available but when i get there they said they only have DS1302 witch is different chip ! although i have tried hardly to hooked up and make it work with My rpi but no luck . then i ordered the one that you recommend but it will take about Five weeks to deliver "i live in 3rd world country
"until then i have decided to do the following :
- installing hardware timer that only allow power to entire project from 07:00 PM to11:00 PM (Real Time) it will allow power to the project only in that window
http://www.acehardware.co.id/ace_media/p...imer_1.jpg
- put this line in crontab @reboot sudo date -s "04-JAN-2014 19:00:00"; (Dummy Time)
- schedule sip to run daily at 19:30 (Dummy Time)
- schedule auto system shutdown at 23:00 using cron tab (Dummy Time)
- since there is not any online ntp in the surroundings the rpi will stick to the dummy time
- Irrigation will run during that time
as soon as i have deployed everything i will post the entire project diagrams and pictures in desired forum
many thanks again for this nice community Dan
Shad