.. include:: ../substitutions.rst
.. include:: stdout.rst

I2C
===

The phyCORE-RT1170 module provides support for Inter-Integrated Circuit (I2C) communication, enabling connections with a variety of external I2C-compatible devices. This standard two-wire bus is commonly used for low-speed communication between integrated circuits on the same board or across short distances.

The i.MX RT1170 processor includes two I2C controllers. For in-depth technical information, refer to the *I2C Interface* chapter in the |hw-manual-link|.

I2C Buses
---------

The phyBOARD-Atlas RT1170 exposes two I2C buses through the carrier board:

* ``lpi2c2``
* ``lpi2c5``

Each bus is connected to specific onboard peripherals, as shown below.

.. list-table:: lpi2c2 Devices
   :header-rows: 1

   * - Interface
     - Address (7-bit)
   * - EEPROM
     - 0x50
   * - EEPROM Identification Page
     - 0x58

.. list-table:: lpi2c5 Devices
   :header-rows: 1

   * - Interface
     - Address (7-bit)
   * - Audio Codec
     - 0x18
   * - Accelerometer/Gyroscope (ICM-40627)
     - 0x69

Accessing I2C Devices via Shell
-------------------------------

To interact with I2C devices from the command line, begin by scanning the bus for connected peripherals. The example below scans the ``lpi2c5`` bus:

.. code-block:: console
   :substitutions:

   |target-prompt| i2c scan lpi2c5
   |intf-i2c-scan|

In this case, the scan reveals two devices: the audio codec at address ``0x18`` and the accelerometer at address ``0x69``. To read a register from a device, use the ``i2c read`` command followed by the bus name, device address, and register offset:

.. code-block:: console
   :substitutions:

   |target-prompt| i2c read lpi2c5 0x18 0
   |intf-i2c-read|

.. note::
   Direct register access via the I2C shell commands is primarily intended for debugging. For production use, it is strongly recommended to access I2C devices through dedicated drivers whenever possible.

ICM-40627 Accelerometer/Gyroscope Example
------------------------------------------

Rather than reading raw registers, devices with a Zephyr sensor driver, such as the ICM-40627 at ``0x69``, can be read through the sensor shell subsystem. Use ``sensor get`` with the device's node name to fetch all of its channels:

.. code-block:: console
   :substitutions:

   |target-prompt| sensor get icm40627@69

.. code-block:: none
   :caption: Expected Output

   channel type=0(accel_x) index=0 shift=6 num_samples=1 value=9869222577ns (-2.748544)
   channel type=1(accel_y) index=0 shift=6 num_samples=1 value=9869222577ns (-0.622493)
   channel type=2(accel_z) index=0 shift=6 num_samples=1 value=9869222577ns (7.067682)
   channel type=3(accel_xyz) index=0 shift=6 num_samples=1 value=9869222577ns, (-2.748544, -0.622493, 7.067682)
   channel type=4(gyro_x) index=0 shift=6 num_samples=1 value=9869222577ns (-0.002128)
   channel type=5(gyro_y) index=0 shift=6 num_samples=1 value=9869222577ns (-0.004256)
   channel type=6(gyro_z) index=0 shift=6 num_samples=1 value=9869222577ns (0.010641)
   channel type=7(gyro_xyz) index=0 shift=6 num_samples=1 value=9869222577ns, (-0.002128, -0.004256, 0.010641)
   channel type=12(die_temp) index=0 shift=6 num_samples=1 value=9869222577ns (36.594201)

The accelerometer and gyroscope channels report values in m/s² and rad/s respectively, and ``die_temp`` reports the sensor's internal die temperature in °C.

EEPROM Uptime Counter Example
-----------------------------

.. jinja::
   :file: templates/i2c-uptime-counter.jinja

Source Code
~~~~~~~~~~~

.. literalinclude :: source-code/uptime_counter.c
   :language: c

For more information see the |http-link-intf-i2c-uptime-counter| file.

.. include:: ../../common/support-disclaimer-us.rst