1 pot and 2 or more Arduino's

:) Hello everyone :) Just a quick question. Can I have one pot on my Arduino control the analog input as well as controlling an analog input of several other Arduino's? If so, would I use only one wire for each of the other Arduino's, connected to the wiper of my first Arduino's pot? Or can it be done serially? Thanks :)

Can I have one pot on my Arduino control the analog input as well as controlling an analog input of several other Arduino's?

yes.

Not sure what you mean by "serially" in this context.

Thanks Groove!! What I meant by "serially" was the possibility of having the second and third Arduino and so on, sharing a connection between their analog in's without having to run a separate wire from each of the Arduino's running back to the first one. Sorry to make it sound so complicated!! :)

Ok, I've done some tests using 2 Arduino's and found some problems! First I took a connection from the pot wiper from the first Arduino and connected it to the analog in of the second Arduino. I found that I also needed to take a ground connection from the pot and connect it to ground on the second Arduino, this was probably obvious to most people ;D. Ok, it works but here is my problem now....I am using a pot on the first Arduino to control a flashing LED and this same pot will control the flashing LED of the second Arduino except both the LED's drift in and out of sync! Can anyone explain to me what is happening here and how I might remedy this? Thanks :)

this was probably obvious to most people

Yep

Can anyone explain to me what is happening here

The crystals on the two arduinos are running at slightly different frequencies so in time you will see a drift. This is inevitable using two oscillators.

Solutions are tricky:- 1) Phase lock one arduino to the oscillator of the other. or 2) Run them off the same clock signal - they have to be close to each other for this to work. Nether is something suitable for a beginner. If you look at your problem you are best designing round this.

Thanks GRUMPY_MIKE :) Everything starts out with a simple idea and then you run into trouble :( Basically I have some modded Auduino's and I have gated their audio output using an LED against an LDR. My dream is to use several together and have that pulsing sound synchronised. Possibly the easiest way around this would be to connect all the LED's needed for each Arduino directly back to the first Arduino and have them controlled there :)

My dream is to use several together and have that pulsing sound synchronised

So if you have several arduins (not sure what you want several) then apply the same synchronising stimulus to each arduino. In this way the different boards are periodically synchronised just like asynchronous serial communications thus giving them little time to drift from each other.

Perfect! The point of all of this is several musicians each with their own Auduino. However, one Auduino needs to control the gating of all the others. If I run several cables from the digital out's of the controller (main Auduino) to power and control the LED's that are already on the other Auduinos, what lengths of cable can I safely use without getting into trouble? :)

what lengths of cable can I safely use without getting into trouble?

Good question, pity there is no definite answer. It depends a lot on the speed of signal you are trying to get through. Probably anything over 10 yards and you have to do special stuff. How special depends on how long. The simplest 'stuff' would be to put it through a transistor, have a collector resistor connected up to 12V, then at the other end put it through another transistor before feeding it into the input. You can go about a quarter of a mile like that.

Ok excellent GRUMPY_MIKE. The idea of having a bunch of musicians 1/4 of a mile apart is hilarious. I'll keep the transistors in mind though because you never know! I'm only looking at 10 feet of cable at most for each LED so by your reassuring account I should be safe :) Thanks for your generous help :)

The idea of having a bunch of musicians 1/4 of a mile apart is hilarious.

In my experience it is the only safe distance for musicians. ;)