동영상 : https://youtu.be/yLKa3em787A
<* UART를 이용한 체팅 *>
- 아두이노 2대를 이용하여 아두이노간에 체팅하기
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#include <SoftwareSerial.h>

SoftwareSerial UARTserial(7, 8); // RX, TX

void setup()
{
  // Open serial communications and wait for port to open:
  Serial.begin(9600);
  Serial.println("SEOUL DIGITAL UNIVERSITY!");

  // set the data rate for the SoftwareSerial port
  UARTserial.begin(9600);
}

void loop() // run over and over
{
  // Receive from bluetooth and send it to PC
  if (UARTserial.available())
    Serial.write(UARTserial.read());

  if (Serial.available())
    UARTserial.write(Serial.read());
}