Arduino sketch to receive bytes from Serial Port 1 and print them in hex to the Serial Monitor

RS485_Serial_Echo.ino

/*
  This simple sketch receives bytes on the hardware serial port
  and echos it to the Arduino Serial Monitor (over USB)
  The bytes are printed out as a hexadecimal string

  This sketch requires an Arduino that has a separate
  serial port for the USB port - such as the Arduino Leonardo

   Serial: Serial Monitor (USB)
   Serial1: Hardward serial (Pins 0 and 1) connected
   
  The enablePin is used to configure a RS-485 transceiver into receive mode.
  
  Author: Nicholas Humfrey
  License: https://unlicense.org
*/

int enablePin = 2;
uint8_t buffer[256];

void setup()
{
    // Configure Serial1 (hardware serial port)
    pinMode(enablePin, OUTPUT);
    digitalWrite(enablePin, LOW);
    Serial1.begin(9600);

    // Configure USB Serial
    Serial.begin(57600);
    while (!Serial);
    Serial.println("RS-485 Echo Sketch Started");
}

void loop()
{
    int available = Serial1.available();

    if (available > 0)
    {
        Serial.print(available, DEC);
        Serial.println(" bytes available");

        int read = Serial1.readBytes(buffer, sizeof(buffer));
        Serial.print(read, DEC);
        Serial.println(" bytes read");

        for(int i=0; i<read; i++) {
            int n = buffer[i];
            Serial.print("0x");
            Serial.print(n < 16 ? "0" : "");
            Serial.print(n, HEX);
            Serial.print(" ");
        }
        Serial.println();
    }

    delay(100);
}