write()

Description

Writes data from a slave device in response to a request from a master, or queues bytes for transmission from a master to slave device (in-between calls to beginTransmission() and endTransmission()).

Syntax


Wire.write(value)
Wire.write(string)
Wire.write(data, length)


Parameters

value: a value to send as a single byte
string: a string to send as a series of bytes
data: an array of data to send as bytes
length: the number of bytes to transmit

Returns

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

Example

#include <Wire.h>

byte val = 0;

void setup()
{
  Wire.begin(); // join i2c bus
}

void loop()
{
  Wire.beginTransmission(44); // transmit to device #44 (0x2c)
                              // device address is specified in datasheet
  Wire.write(val);            // sends value byte  
  Wire.endTransmission();     // stop transmitting

  val++;        // increment value
  if(val == 64) // if reached 64th position (max)
  {
    val = 0;    // start over from lowest value
  }
  delay(500);
}

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The text of the 86Duino reference is a modification of the Arduino reference, and is licensed under a Creative Commons Attribution-ShareAlike 3.0 License. Code samples in the reference are released into the public domain.