write()

Description

This function writes data from a peripheral device in response to a request from a controller device, or queues bytes for transmission from a controller to peripheral device (in-between calls to

beginTransmission()

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

The number of bytes written (reading this number is optional).

Example

1#include <Wire.h>
2
3byte val = 0;
4
5void setup() { Wire.begin(); // Join I2C bus }
6
7void loop() { Wire.beginTransmission(44); // Transmit to device number
844 (0x2C)
9
10    Wire.write(val);             // Sends value byte
11    Wire.endTransmission();      // Stop transmitting
12
13    val++;                       // Increment value
14
15    // if reached 64th position (max)
16    if(val == 64) {
17        val = 0;                   // Start over from lowest value
18    }
19
20        delay(500);
21    }