I2C Library

Summary

A software defined, industry-standard, I²C library that allows you to control an I²C bus via xCORE ports. I²C is a two-wire hardware serial interface, first developed by Philips. The components in the libary are controlled via C using the XMOS multicore extensions (xC) and can either act as I²C master or slave.

The libary is compatible with multiple slave devices existing on the same bus. The I²C master component can be used by multiple tasks within the xCORE device (each addressing the same or different slave devices).

The library can also be used to implement multiple I²C physical interfaces on a single xCORE device simultaneously.

Features

• I²C master and I²C slave modes.
• Supports speed up to 400 Kb/s (I²C Fast-mode).
• Clock stretching support.
• Synchronous and asynchronous APIs for efficient usage of processing cores.

Typical Resource Usage

.. resusage::

  * - configuration: Master
    - globals: port p_scl = XS1_PORT_1A; port p_sda = XS1_PORT_1B;
    - locals: interface i2c_master_if i[1];
    - fn: i2c_master(i, 1, p_scl, p_sda, 100);
    - pins: 2
    - ports: 2 (1-bit)
  * - configuration: Master (single port)
    - globals: port p = XS1_PORT_4A;
    - locals: interface i2c_master_if i[1];
    - fn: i2c_master_single_port(i, 1, p, 100, 0, 0, 0);
    - pins: 2
    - ports: 1 (multi-bit)
    - target: XCORE-200-EXPLORER
  * - configuration: Master (asynchronous)
    - globals: port p_scl = XS1_PORT_1A; port p_sda = XS1_PORT_1B;
    - locals: interface i2c_master_async_if i[1];
    - fn: i2c_master_async(i, 1, p_scl, p_sda, 100, 20);
    - pins: 2
    - ports: 2 (1-bit)
  * - configuration: Master (asynchronous, combinable)
    - globals: port p_scl = XS1_PORT_1A; port p_sda = XS1_PORT_1B;
    - locals: interface i2c_master_async_if i[1];
    - fn: i2c_master_async_comb(i, 1, p_scl, p_sda, 100, 20);
    - pins: 2
    - ports: 2 (1-bit)
  * - configuration: Slave
    - globals: port p_scl = XS1_PORT_1A; port p_sda = XS1_PORT_1B;
    - locals: interface i2c_slave_callback_if i;
    - fn: i2c_slave(i, p_scl, p_sda, 0);
    - pins: 2
    - ports: 2 (1-bit)

Software version and dependencies

.. libdeps::

Related application notes

The following application notes use this library:

• AN00156: How to use the I2C master library
• AN00157: How to use the I2C slave library
• AN00181: xCORE-200 explorer accelerometer demo