How do I use same variables between multiple Arduinos? - variables

Question

I have multiple Arduinos. I will use one of them as master and it must share variables to other Arduinos. For example, master Arduino will change integer A value, and this integer A value will be changed at other Arduinos as well. How do I connect or communicate those multiple Arduinos? Thanks in advance for any kind of suggestions.

Answer 1

I did some research and found how to communicate between two Arduinos. First, we will upload codes below then connect our Arduinos as in this image:
Connection of Arduinos
If you connect Arduinos before uploading codes, Arduino will give an error. So be sure that you upload your codes before connection. Here is receiver code:
After that, you will receive exact value from sender arduino. You can check it on receiver serial port screen. Hope this helps everyone :)
//Receiver Arduino Code
String a;
int yyy;
void setup()
{
Serial.begin(9600);
}
void loop()
{
while(Serial.available())
{
a = Serial.readString(); //reading value as String
//yyy=a.toInt(); //this one is for the converting string value to if it is an integer
Serial.println(a);
Serial.println(a.length());
Serial.println(a.charAt(a.length()-1));
}
}
Here is sender code:
//Sender Arduino code
void setup()
{
Serial.begin(9600);
}
void loop()
{
Serial.println("1234i");
delay(2000);
}