Datasheet

Flyport Wi-Fi and Ethernet Programmer's guide framework 2.3 (rev 1.0) www.openpicus.com

I2C Communication Protocol

I2C is a 2 wire serial communication widely used in embedded electronics to connect devices such as

external memory and more.

Unlike the UART, I2C has a Master-Slave architecture, where the Master starts all the requests of

communication. The baud rate is given by the Master, and the most used values are 100kb/s (low

speed) and 400kb/s (high speed).

I2C bus needs pull-up resistors and dedicated open collector pins.

To use the I2C protocol has s a determined sequence of operations for starting, stopping, write, read

and checking if the data was transmitted ok.

For more information see the link:

http://en.wikipedia.org/wiki/I%C2%B2C

OpenPicus framework offers some functions to easily manage the I2C communication, using Flyport

as a Master. In this way it’s possible to communicate with I2C slave devices and read/write their

issue is to check that any device connected on the bus must have a different address.

I2C Basic Functions

Initialize I2C → I2CInit(BYTE speed);

This function initializes the I2C at the specified speed of communication.

Parameters:

speed: it can be HIGH_SPEED (400K) or LOW_SPEED (100K)

Send a Start condition → I2CStart();

This function sends a start sequence on the I2C bus.

Parameters:

none

Send a Restart condition → I2CRestart();

This function resends a start sequence on the I2C bus.

Parameters:

none

Send a Stop condition → I2CStop();

This function sends a stop sequence on the I2C bus.

Parameters:

none