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<h2>int Serial.available()</h2>
<h4>Description</h4>
<p>Get the number of bytes (characters) available for reading over the serial port.
</p>
<p class='vspace'></p><h3>Parameters</h3>
<p>None
</p>
<p class='vspace'></p><h4>Returns</h4>
<p>The number of bytes are available to read in the serial buffer, or 0 if none are available. If any data has come in, Serial.available() will be greater than 0. The serial buffer can hold up to 128 bytes.
</p>
<p class='vspace'></p><h3>Example</h3>
<pre>
int incomingByte = 0; // for incoming serial data
void setup() {
Serial.begin(9600); // opens serial port, sets data rate to 9600 bps
}
void loop() {
// send data only when you receive data:
if (Serial.available() > 0) {
// read the incoming byte:
incomingByte = Serial.read();
// say what you got:
Serial.print("I received: ");
Serial.println(incomingByte, DEC);
}
}
</pre>
<p class='vspace'></p><p><strong>Arduino Mega example:</strong>
</p>
<p class='vspace'></p><pre>
void setup() {
Serial.begin(9600);
Serial1.begin(9600);
}
void loop() {
// read from port 0, send to port 1:
if (Serial.available()) {
int inByte = Serial.read();
Serial1.print(inByte, BYTE);
}
// read from port 1, send to port 0:
if (Serial1.available()) {
int inByte = Serial1.read();
Serial.print(inByte, BYTE);
}
}
</pre>
<p class='vspace'></p><h4>See also</h4>
<ul><li><a class='wikilink' href='Serial_Begin.html'>Serial.begin</a>(speed)
</li><li><a class='wikilink' href='Serial_Read.html'>Serial.read</a>()
</li><li><a class='wikilink' href='Serial_Print.html'>Serial.print</a>(data)
</li><li><a class='wikilink' href='Serial_Println.html'>Serial.println</a>(data)
</li></ul><p class='vspace'></p><p><a class='wikilink' href='index.html'>Reference Home</a>
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