Indicates if the specified Serial port is ready.

On the boards with native USB, if (Serial) (or if(SerialUSB) on the Due) indicates whether or not the USB CDC serial connection is open. For all other boards, and the non-USB CDC ports, this will always return true.

This was introduced in Arduino IDE 1.0.1.


if (Serial)

Parameter Values

  • None

Return Values

  • Returns true if the specified serial port is available. This will only return false if querying the Leonardo's USB CDC serial connection before it is ready. Data type: bool.

Example Code

void setup() { //Initialize serial and wait for port to open: Serial.begin(9600); while (!Serial) { ; // wait for serial port to connect. Needed for native USB } } void loop() { //proceed normally }

See Also

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