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Serial.write()

Description

Writes binary data to the serial port. This data is sent as a byte or series of bytes; to send the characters representing the digits of a number use the print() function instead.

Syntax

Serial.write(val)
Serial.write(str)
Serial.write(buf, len)

Arduino Mega also supports:

Serial1, Serial2, Serial3 (in place of Serial)

Parameters

val: a value to send as a single byte

str: a string to send as a series of bytes

buf: an array to send as a series of bytes

Returns

size_t

write() will return the number of bytes written, though reading that number is optional

Example Code

void setup(){
  Serial.begin(9600);
}

void loop(){
  Serial.write(45); // send a byte with the value 45

   int bytesSent = Serial.write(“hello”); //send the string “hello” and return the length of the string.
}