Modified example to not generate confusion

Only Arduino Mega was mentioned, but actually many boards have more than one Serial port

build/shared/examples/04.Communication/MultiSerial/MultiSerial.ino

@@ -0,0 +1,42 @@
+/*
+  Multple Serial test
+
+ Receives from the main serial port, sends to the others.
+ Receives from serial port 1, sends to the main serial (Serial 0).
+
+ This example works only with boards with more than one serial like Arduino Mega, Due, Zero etc
+
+ The circuit:
+ * Any serial device attached to Serial port 1
+ * Serial monitor open on Serial port 0:
+
+ created 30 Dec. 2008
+ modified 20 May 2012
+ by Tom Igoe & Jed Roach
+ modified 27 Nov 2015
+ by Arturo Guadalupi
+
+ This example code is in the public domain.
+
+ */
+
+
+void setup() {
+  // initialize both serial ports:
+  Serial.begin(9600);
+  Serial1.begin(9600);
+}
+
+void loop() {
+  // read from port 1, send to port 0:
+  if (Serial1.available()) {
+    int inByte = Serial1.read();
+    Serial.write(inByte);
+  }
+
+  // read from port 0, send to port 1:
+  if (Serial.available()) {
+    int inByte = Serial.read();
+    Serial1.write(inByte);
+  }
+}

build/shared/examples/04.Communication/MultiSerial/MultiSerial.txt

@@ -0,0 +1 @@
+Use two of the serial ports available on the Arduino board.