hi,
i have 7 arduino micros used for button boxes for my simpit. each arduino has some LED's connected to them. now was i wondering. coud i wire 1 switch to 7 different arduinos to turn all LED's off?
best regards,
devon
Sure You can. Let one controller be the master setting a digital output to "Go", or "Stop" and let the other units monitour that signal. Remember, they must all have GND common!
Yes.
Just be aware that a long wire might pick up noise.
You will have to have the GNDs of all the Arduinos connected. Then if the I/O pin on each Arduino is kept HIGH with pinMode(INPUT_PULLUP); the one switch can pull them all to GND.
...R
thnx all, i'll give it a shot after easter 
But you might care to explain why you are using multiple modules in the first place and what a "simpit" actually is? 
Probably a "simulator cockpit" for a PC airplane simulator
OK, but why so many MCUs?
i have this many MCU's since i have allot of buttons and switches and LEDs to control and to make it easier for me to organize i use a micro per controller device. (it's btw not a airplain simulator, it's and truck simulator)
Hi,
Have you considered connecting them all using CanBus.
Tom..
i have this many MCU's since i have allot of buttons and switches and LEDs to control and to make it easier for me to organize i use a micro per controller device.
So ignoring the simple use of a port expanders or shift registers, which is the grownups solution.
TomGeorge:
Hi,
Have you considered connecting them all using CanBus.Tom..
i have actually no knowlage of canbus so i wouldn't know how to connect multiple arduinos using canbus. i don't even know how i could make a canbas components word with an arduino (allot of truck/car parts work with canbus)
Grumpy_Mike:
So ignoring the simple use of a port expanders or shift registers, which is the grownups solution.
i have very basic knowlage of arduino. is there a way to learn more advanced stuff like that or using canbus systems?
Grumpy_Mike:
So ignoring the simple use of a port expanders or shift registers, which is the grownups solution.
They may not be the simplest solution for a newbie and the potential cost saving is probably not an important issue.
However if I needed a lot of I/O pins I would use a Mega.
...R
They may not be the simplest solution for a newbie
I never said that it would be the simplest solution. However, it is not a complex solution and once mastered you need never run out of I/O irrespective of what ever processor you go on to use in the future.
is there a way to learn more advanced stuff l
Yes, but the first thing you must happen is that you have to be aware that this sort of things exist. Which is where posts to this forum come in. We know are audience is about 80% beginners which is why we are always on the lookout to explain concepts to them they might not know.
For example many beginners don't know that analogue inputs can be used as digital inputs and outputs as well providing you set the pin mode correctly. This often saves pins and allows them to use only one processor.
When ever you can you try and use one processor. There are of course exceptions to this where two or more processors are required but these tend to be more complex projects.
So the best place to learn is once you know about the thing you want to learn about is to type that thing into a search engine ( other googles are available ) and you will have lots of people trying to sell you one. Forget the cheap china stuff and go to a respected site like Sparkfun or Adafruit. They will often have tutorials that explain how to use their product. As a last resort ask here if anyone can post you a respectable link.
One tip however, never, ever, try and learn something new from instructables, they are unregulated and anyone can post there. This results in most electronics articles being pure crap. There are the occasional good ones but you have to know how to spot mistakes in order to know if they are any good and in that case you probably know it anyway.
thnx Grumpy_Mike
i'll use your advice
btw i knew i could use analog as digital pins but not visa versa 
btw i knew i could use analog as digital pins but not visa versa
Sorry if I phrased that wrong but you can’t use digital pins as analogue pins.
Yes it is hard to know who knows what from an initial post.