Serial.availableForWrite()

Description

Get the number of bytes (characters) available for writing in the serial buffer without blocking the write operation.

Syntax

Serial.availableForWrite()

Parameter Values

  • Serial: serial port object. See the list of available serial ports for each board on the Serial main page.

Return Values

  • The number of bytes available to write.

Example Code

String myString = "Welcome to ArduinoGetStarted.com!\n"; void setup() { Serial.begin(9600); // opens serial port, sets data rate to 9600 bps int wlen = Serial.availableForWrite(); // prints the received data Serial.print("TX buffer size: "); Serial.println(wlen); } void loop() { // check if Tx buffer is enough to write the string if (Serial.availableForWrite() > myString.length()) { // prints the string Serial.print(myString); delay(1000); } }
  • The result on Serial Monitor:
  • COM6
    Send
    TX buffer size: 63 Welcome to ArduinoGetStarted.com! Welcome to ArduinoGetStarted.com! Welcome to ArduinoGetStarted.com! Welcome to ArduinoGetStarted.com!
    Autoscroll Show timestamp
    Clear output
    9600 baud  
    Newline  

※ NOTES AND WARNINGS:

Serial functions are not only used for the communication between an Arduino board and Serial Monitor of Arduino IDE but also used for the communication between:

  • An Arduino board and other Arduino board
  • An Arduino board and other sensors/devices
  • An Arduino board and computer (any Serial software on computer)

See Also

ARDUINO BUY RECOMMENDATION

Arduino UNO R3
Arduino Starter Kit
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