Arduino Kit: Arduino to Arduino UART

https://peppe8o.com/arduino-uart-communication/

arduino-uart-wiring-diagram

Section 1: “uart-trasmitter-code.ino” code

This section contains the code explanation for the transmitter, which performs Serial.write(x). The x is the value that reads from the push button. The push button, when pressed, becomes high, which means that it becomes 1. The baud rate set for the communication is 9600. The LEDs are set here to get the value from the receiver to turn the LED on and off.

#define PB 2
void setup()
{
  Serial.begin(9600);
  pinMode(13, OUTPUT);
  pinMode(PB, INPUT);
}
void loop()
{ byte x=digitalRead(PB);
  Serial.write(x);
  if(Serial.available())
  {
  byte rec=Serial.read();
  if(rec==1)
  {
    digitalWrite(13,HIGH);
  }    
  else digitalWrite(13,LOW);
  }
}

Section 2: “uart-receiver-code.ino” code

This is the section for the receiving part. Both the receiving and transmitting codes look the same as the communication is happening in half-duplex. So the commands send from the transmitter and received at the receiver by the serial.read() if the value is 1, then the LED turns on; otherwise, it remains off.

#define PB 2
void setup()
{
  Serial.begin(9600);
  pinMode(13, OUTPUT);
  pinMode(PB, INPUT);
}
void loop()
{ byte x=digitalRead(PB);
  Serial.write(x);
  if(Serial.available())
  {
  byte rec=Serial.read();
  if(rec==1)
  {
    digitalWrite(13,HIGH);
  }    
  else digitalWrite(13,LOW);
  }
}

Simulating the Arduino UART communication

The simulation is made to give the demo, as in the picture it can be seen that the led on the receiver side is on, which happened by pressing the button at the transmitter. Similarly, the second figure, displays that LED is on the transmitter side, in which the button at the receiver is pressed. On pressing the button, the value becomes 1, which means that the transmitted value is 1, while without pressing the button, the value is 0.