So im working on a personal project for my truck, I would like to ONLY turn on the board and have it do its thing at specific times.
At the moment not sure yet if im going to manually turn it on and off with a switch or wire it eventually to the truck wiring so that it comes on and off when certain things happen.
If I wire everything directly to the truck wiring, I don't want to have the board and sensors working just cause it has power. So id like some "external" way to turn the board on and begin the sensing.
Im going to use the proximity sensors for one project, but eventually would like to add more things to the truck, but right now the simple project just to see how it would work is the proximity.
Now sure if this is the right area to post this, so please move if not.
If you can switch a relay on with the signal you want to switch on your arduino with, then do so, and then once powered up the arduino then gives signal to keep relay on. When arduino has finished what it is doing then it can switch it's self off.
Leave the processor running all the time that the truck is switched on. Then it can control the things it needs, when it needs.
You could even wire it to unswitched power so it also runs while the truck is off. That would flatten the battery over several months, as the power draw is really quite small compared to most things on an automobile.
BobEdge:
If you can switch a relay on with the signal you want to switch on your arduino with, then do so, and then once powered up the arduino then gives signal to keep relay on. When arduino has finished what it is doing then it can switch it's self off.
With this method you are referring to wiring up a relay within the truck to a signal//function that will trigger the power correct?
MorganS:
Leave the processor running all the time that the truck is switched on. Then it can control the things it needs, when it needs.
You could even wire it to unswitched power so it also runs while the truck is off. That would flatten the battery over several months, as the power draw is really quite small compared to most things on an automobile.
With this method it would run when not really in use I guess, but if I decide to leave and use the setup full time, it really would only need to run for a few seconds MAYBE minute or two, but that's all.
I was trying to find a way to cut out me as a additional step in the process to actually make it all work.
Computers exist to serve us. If the computer has to wait several months for you to press a button then it can wait by checking that button several thousand times per second. It is "really in use" because it is waiting for you.
You may consider power consumption as a design metric but on an automobile, a few milliamps is close enough to 'nothing'.