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Wire

## 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);
}
[Get Code]

#### See also

- WireRead()
- WireBeginTransmission()
- WireEndTransmission()
- Serial.write()

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