Any suggestions ?

Hello guys ,

I'm working on a system consists of 2 sensors + buzzer + LCD screen .
Now the idea that I struggled to accomplish is that I need a way to make the work of second sensor and LCD are conditional with the work of the first sensor .
for example :
" The light sensor + LCD screen will not work until the temperature and humidity ( DHT11 ) are reached to specific values . I need a way to turn on the second sensor once the required measurements are gained from the first sensor " .
Once I connected the battery with the UNO , both sensors + LCD start working and draw current ( which reduces the battery life ) ,

I want to extend battery life as mush as possible , Is there any method to do that ?!
I heard about sleep mode , but actually I don't know what is it exactly or how to apply it in my code .

Hi FOS,

Did you google arduino sleep mode? This is the first hit arduino sleep mode.
Have a look at that and see if that helps.

You asked: 'Is there any method to extend battery life as mush as possible?'

Yes there is. Check out Nick Gannon's example on this site for a really cool and complete solution, but also google "extend battery life arduino".

teunman:
Hi FOS,

Did you google arduino sleep mode? This is the first hit arduino sleep mode.
Have a look at that and see if that helps.

Hey teunman, I didn't see your post when I posted - thanks for your link! it's a very] useful page!

Nick Gammon's power saving tutorial

...R

any suggestions ? #1 ) read how to use this forum and the proper way to write a subject line to draw people to your post that have experience in the area you have questions.

#2) go through the IDE examples. that is just basic training and learning the fundaments.

in them you will find how to blink and how to use a button. you will also find how to time things.

in your case, you want to read a sensor, then, if the reading is above some point, do a different thing.

that is just putting the examples together.

#3) display screens and batteries should not be used automatically. there is zero need for the screen to work when a human is not there looking at it. so every use, while no one is present is wasted energy.
and if a human is there, a simple button to have the display turn on would be much better. and a timer to turn it off shortly after displaying the information.

Thanks All ! , Those links helped me a lot