Connect 2 arduinos with one analog switch?

let's say i want to connect two arduinos with one analog switch, on one side is RF 433 receiver with led on pin 13 and on another arduino is transmitter and i want to put between them one physical analog switch that when i turn on switch transmitter send impuls to receiver and led turns on?

here is project without analog switch

http://aruselektronika.blogspot.hr/2016/04/rf-433-push-button-led.html

I think the first thing you need to explain is what you mean by "analog switch". My concept of a switch is something that is either off or on - in other words digital.

And I don't even know what language that link is written in :slight_smile:

...R

Robin2:
I think the first thing you need to explain is what you mean by "analog switch". My concept of a switch is something that is either off or on - in other words digital.

And I don't even know what language that link is written in :slight_smile:

...R

let's keep it simple: when i connect 2 arduinos with one wire then transmitter send impuls to receiver and led turn on, or i can cut wire and put one switch which we all use to turn on light in our houses...

Edward5:
let's keep it simple: when i connect 2 arduinos with one wire then transmitter send impuls to receiver and led turn on, or i can cut wire and put one switch which we all use to turn on light in our houses...

That sounds like a regular ON/OFF switch - there is nothing analog about it.

I'm not sure from your latest description if you want to put a switch in the connection between two Arduinos OR if you want to replace one of the Arduinos with a switch. OR maybe you want the switch as well as the two connected Arduinos.

All of these are perfectly possible.

...R

Robin2:
That sounds like a regular ON/OFF switch - there is nothing analog about it.

I'm not sure from your latest description if you want to put a switch in the connection between two Arduinos OR if you want to replace one of the Arduinos with a switch. OR maybe you want the switch as well as the two connected Arduinos.

All of these are perfectly possible.

...R

i want connect two arduinos with one wire, on that wire is switch ON/OFF, simple switch, on the other arduino is one led diode, when turn switch on the led is on, i repeat, between two arduino is only one wire with switch, only positive, no negative, if this is not possible, can i connect them together like this: the gnd from one arduino goes to another arduino and positive let's say goes through the air with RF433 transmitter, or other wireless suitable transmitter?

It would require at least two wires. One for the switch and the grounds would also need to be connected.

If you use wireless there would be no need for any wire between the two Arduinos.

The more you tell us the more confusing this becomes. It now has all the hallmarks of an XY Problem.

Tell us what your project is and you will probably get useful advice.

...R

you seem confusing about my project, i know...

i would like to make project to test continuity for example if my wire is 30 meters long and i cant have the ends of the wire near my multimeter i want to make continuity tester that can do it, is this possible, i already done this with two wires with gnd and positive, but i cant do this with only one wire.

Is there any way that i can make it happen with one wire?

To test continuity you kind of have to connect to two points. How would you even define continuity with only one point?

That's kind of like trying to measure distance with only one point. The distance to where? Same here. If you only connect to one point, continuity to where?

Delta_G:
To test continuity you kind of have to connect to two points. How would you even define continuity with only one point?

That's kind of like trying to measure distance with only one point. The distance to where? Same here. If you only connect to one point, continuity to where?

i was telling you before, maybe the second wire can be for example RF433 wireless module?

You cannot send a signal over a single wire. There must be a complete circuit - out and return.

When an Arduino uses digitalWrite() to make a pin HIGH it is only high in the sense that it measures 5v compared to Arduino GND. If you take another piece of wire from your toolbox and leave it on your workbench unconnected to anything and try to measure the voltage with one probe of your multimeter on the HIGH pin and one of the wire it will just read 0v. (And I just tried that with a battery just to be 100% certain).

The return part must be another wire, It cannot be wireless.

...R

Hi,
Can you use the EARTH as your return?

There will be resistance, but if you need to detect just a CLOSED/OPEN condition, measuring the loop current will be enough.

Tom... :slight_smile:

TomGeorge:
Can you use the EARTH as your return?

I was wondering about that. The original morse telegraphs used that but I have no idea what voltage they worked at. Would it work at 5v?

And it may be more trouble than its worth to get a reliable connection into the soil at each end.

...R

so, can this be done with gnd?

Edward5:
so, can this be done with gnd?

You must understand that what @TomGeorge means by "earth" is a connection into the soil in your garden - a connection to the planet Earth.

The word "GND" or "Ground" is often used in electrical circuits to mean the negative battery terminal which a very limited notion of "ground"

And to answer your question, I suspect you will need to experiment to find out.

...R

Hi,
What is it that needs a single wire to be tested for continuity?
What does the wire do?

Thanks.. Tom... :slight_smile:

Robin2:
You must understand that what @TomGeorge means by "earth" is a connection into the soil in your garden - a connection to the planet Earth.

The word "GND" or "Ground" is often used in electrical circuits to mean the negative battery terminal which a very limited notion of "ground"

And to answer your question, I suspect you will need to experiment to find out.

...R

I understand, that mean, this, what i imagined, can't be done.

p.s. thanks anyway

TomGeorge:
Hi,
What is it that needs a single wire to be tested for continuity?
What does the wire do?

Thanks.. Tom... :slight_smile:

let's say i want test neutral or phase in my house, if distance is long i can make tester with two wires to close my circuit and i will get led diode lighting, if my wires are good if they are not cutted off, but if i got on my place of testing gnd, neutral and phase and if let's say two of them are somewhere in the middle broken, and i can't get continuity reading i will need manualy pull them out of the canal from my wall if there is cut somewhere in the middle way, and i can't be sure on which one of three is cut...