/*
James Khan Fab Academy networking and communication week week.
https://fabacademy.org/2021/labs/vancouver/students/james-khan/assignments/week13/

Used the code I developed for my input week as a starting point and modified for communication.
https://fabacademy.org/2021/labs/vancouver/students/james-khan/assignments/week11/

This program is for an SEEED RP2040 board 
and communicates with my self made ATtiny board (with a different program).

This program constantly listens for a message on two seperate serial ports
Serial is the regular connection to the computer via USB
SErial1 is the UART connection to my second board

When a message comes in on either of the serial ports it 
sends the message on the other serial port.
*/

void setup() {
  delay(2000);
  Serial.begin(115200);               // set's up the connection speed, needs to match the other program
  delay(200);
  Serial1.begin(115200, SERIAL_8N1);  //defines a unique Serial addresses:default Serial is USB/computer, Serial1 is RX/TX or UART
  Serial.println("\n--- UART communication with XIAO RP2040 ---");
  Serial.println("-------------------------------------------------------");
}

void loop() {
  if (Serial.available()) {         // If I send anything from the computer's serial monitor
    Serial1.write(Serial.read());   // then rean it and send it over UART to other device   
       // read it and send it out Serial1 (pins 0 & 1)
    digitalWrite(29, HIGH);
    delay(50);
    digitalWrite(29, LOW);          // flashes LED to indicate received sent
  }

  if (Serial1.available()) {        // If anything comes in Serial1 (my connected second board)
    Serial.write(Serial1.read());   // then send it to the computer's serial monitor
    digitalWrite(29, HIGH);
    delay(50);
    digitalWrite(29, LOW);          // flashes LED to indicate received message
  }
}