Documentation/iio/adxl380.rst - linux - Git at Google

 .. SPDX-License-Identifier: GPL-2.0

 ===============
 ADXL380 driver
 ===============

 This driver supports Analog Device's ADXL380/382 on SPI/I2C bus.

 1. Supported devices
 ====================

 * `ADXL380 <https://www.analog.com/ADXL380>`_
 * `ADXL382 <https://www.analog.com/ADXL382>`_

 The ADXL380/ADXL382 is a low noise density, low power, 3-axis accelerometer with
 selectable measurement ranges. The ADXL380 supports the ±4 g, ±8 g, and ±16 g
 ranges, and the ADXL382 supports ±15 g, ±30 g, and ±60 g ranges.

 2. Device attributes
 ====================

 Accelerometer measurements are always provided.

 Temperature data are also provided. This data can be used to monitor the
 internal system temperature or to improve the temperature stability of the
 device via calibration.

 Each IIO device, has a device folder under ``/sys/bus/iio/devices/iio:deviceX``,
 where X is the IIO index of the device. Under these folders reside a set of
 device files, depending on the characteristics and features of the hardware
 device in questions. These files are consistently generalized and documented in
 the IIO ABI documentation.

 The following tables show the adxl380 related device files, found in the
 specific device folder path ``/sys/bus/iio/devices/iio:deviceX``.

 +---------------------------------------------------+----------------------------------------------------------+
 | 3-Axis Accelerometer related device files         | Description                                              |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_scale                                    | Scale for the accelerometer channels.                    |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_filter_high_pass_3db_frequency           | Low pass filter bandwidth.                               |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_filter_high_pass_3db_frequency_available | Available low pass filter bandwidth configurations.      |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_filter_low_pass_3db_frequency            | High pass filter bandwidth.                              |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_filter_low_pass_3db_frequency_available  | Available high pass filter bandwidth configurations.     |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_x_calibbias                              | Calibration offset for the X-axis accelerometer channel. |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_x_raw                                    | Raw X-axis accelerometer channel value.                  |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_y_calibbias                              | y-axis acceleration offset correction                    |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_y_raw                                    | Raw Y-axis accelerometer channel value.                  |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_z_calibbias                              | Calibration offset for the Z-axis accelerometer channel. |
 +---------------------------------------------------+----------------------------------------------------------+
 | in_accel_z_raw                                    | Raw Z-axis accelerometer channel value.                  |
 +---------------------------------------------------+----------------------------------------------------------+

 +----------------------------------+--------------------------------------------+
 | Temperature sensor related files | Description                                |
 +----------------------------------+--------------------------------------------+
 | in_temp_raw                      | Raw temperature channel value.             |
 +----------------------------------+--------------------------------------------+
 | in_temp_offset                   | Offset for the temperature sensor channel. |
 +----------------------------------+--------------------------------------------+
 | in_temp_scale                    | Scale for the temperature sensor channel.  |
 +----------------------------------+--------------------------------------------+

 +------------------------------+----------------------------------------------+
 | Miscellaneous device files   | Description                                  |
 +------------------------------+----------------------------------------------+
 | name                         | Name of the IIO device.                      |
 +------------------------------+----------------------------------------------+
 | sampling_frequency           | Currently selected sample rate.              |
 +------------------------------+----------------------------------------------+
 | sampling_frequency_available | Available sampling frequency configurations. |
 +------------------------------+----------------------------------------------+

 Channels processed values
 -------------------------

 A channel value can be read from its _raw attribute. The value returned is the
 raw value as reported by the devices. To get the processed value of the channel,
 apply the following formula:

 .. code-block:: bash

         processed value = (_raw + _offset) * _scale

 Where _offset and _scale are device attributes. If no _offset attribute is
 present, simply assume its value is 0.

 The adis16475 driver offers data for 2 types of channels, the table below shows
 the measurement units for the processed value, which are defined by the IIO
 framework:

 +-------------------------------------+---------------------------+
 | Channel type                        | Measurement unit          |
 +-------------------------------------+---------------------------+
 | Acceleration on X, Y, and Z axis    | Meters per Second squared |
 +-------------------------------------+---------------------------+
 | Temperature                         | Millidegrees Celsius      |
 +-------------------------------------+---------------------------+

 Usage examples
 --------------

 Show device name:

 .. code-block:: bash

 	root:/sys/bus/iio/devices/iio:device0> cat name
         adxl382

 Show accelerometer channels value:

 .. code-block:: bash

         root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_raw
         -1771
         root:/sys/bus/iio/devices/iio:device0> cat in_accel_y_raw
         282
         root:/sys/bus/iio/devices/iio:device0> cat in_accel_z_raw
         -1523
         root:/sys/bus/iio/devices/iio:device0> cat in_accel_scale
         0.004903325

 - X-axis acceleration = in_accel_x_raw * in_accel_scale = −8.683788575 m/s^2
 - Y-axis acceleration = in_accel_y_raw * in_accel_scale = 1.38273765 m/s^2
 - Z-axis acceleration = in_accel_z_raw * in_accel_scale = -7.467763975 m/s^2

 Set calibration offset for accelerometer channels:

 .. code-block:: bash

         root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
         0

         root:/sys/bus/iio/devices/iio:device0> echo 50 > in_accel_x_calibbias
         root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
         50

 Set sampling frequency:

 .. code-block:: bash

 	root:/sys/bus/iio/devices/iio:device0> cat sampling_frequency
         16000
         root:/sys/bus/iio/devices/iio:device0> cat sampling_frequency_available
         16000 32000 64000

         root:/sys/bus/iio/devices/iio:device0> echo 32000 > sampling_frequency
         root:/sys/bus/iio/devices/iio:device0> cat sampling_frequency
         32000

 Set low pass filter bandwidth for accelerometer channels:

 .. code-block:: bash

         root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency
         32000
         root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency_available
         32000 8000 4000 2000

         root:/sys/bus/iio/devices/iio:device0> echo 2000 > in_accel_filter_low_pass_3db_frequency
         root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency
         2000

 3. Device buffers
 =================

 This driver supports IIO buffers.

 All devices support retrieving the raw acceleration and temperature measurements
 using buffers.

 Usage examples
 --------------

 Select channels for buffer read:

 .. code-block:: bash

         root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_x_en
         root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_y_en
         root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_z_en
         root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_temp_en

 Set the number of samples to be stored in the buffer:

 .. code-block:: bash

         root:/sys/bus/iio/devices/iio:device0> echo 10 > buffer/length

 Enable buffer readings:

 .. code-block:: bash

         root:/sys/bus/iio/devices/iio:device0> echo 1 > buffer/enable

 Obtain buffered data:

 .. code-block:: bash

         root:/sys/bus/iio/devices/iio:device0> hexdump -C /dev/iio\:device0
         ...
         002bc300  f7 e7 00 a8 fb c5 24 80  f7 e7 01 04 fb d6 24 80  |......$.......$.|
         002bc310  f7 f9 00 ab fb dc 24 80  f7 c3 00 b8 fb e2 24 80  |......$.......$.|
         002bc320  f7 fb 00 bb fb d1 24 80  f7 b1 00 5f fb d1 24 80  |......$...._..$.|
         002bc330  f7 c4 00 c6 fb a6 24 80  f7 a6 00 68 fb f1 24 80  |......$....h..$.|
         002bc340  f7 b8 00 a3 fb e7 24 80  f7 9a 00 b1 fb af 24 80  |......$.......$.|
         002bc350  f7 b1 00 67 fb ee 24 80  f7 96 00 be fb 92 24 80  |...g..$.......$.|
         002bc360  f7 ab 00 7a fc 1b 24 80  f7 b6 00 ae fb 76 24 80  |...z..$......v$.|
         002bc370  f7 ce 00 a3 fc 02 24 80  f7 c0 00 be fb 8b 24 80  |......$.......$.|
         002bc380  f7 c3 00 93 fb d0 24 80  f7 ce 00 d8 fb c8 24 80  |......$.......$.|
         002bc390  f7 bd 00 c0 fb 82 24 80  f8 00 00 e8 fb db 24 80  |......$.......$.|
         002bc3a0  f7 d8 00 d3 fb b4 24 80  f8 0b 00 e5 fb c3 24 80  |......$.......$.|
         002bc3b0  f7 eb 00 c8 fb 92 24 80  f7 e7 00 ea fb cb 24 80  |......$.......$.|
         002bc3c0  f7 fd 00 cb fb 94 24 80  f7 e3 00 f2 fb b8 24 80  |......$.......$.|
         ...

 See ``Documentation/iio/iio_devbuf.rst`` for more information about how buffered
 data is structured.

 4. IIO Interfacing Tools
 ========================

 See ``Documentation/iio/iio_tools.rst`` for the description of the available IIO
 interfacing tools.
	.. SPDX-License-Identifier: GPL-2.0

	===============
	ADXL380 driver
	===============

	This driver supports Analog Device's ADXL380/382 on SPI/I2C bus.

	1. Supported devices
	====================

	* `ADXL380 <https://www.analog.com/ADXL380>`_
	* `ADXL382 <https://www.analog.com/ADXL382>`_

	The ADXL380/ADXL382 is a low noise density, low power, 3-axis accelerometer with
	selectable measurement ranges. The ADXL380 supports the ±4 g, ±8 g, and ±16 g
	ranges, and the ADXL382 supports ±15 g, ±30 g, and ±60 g ranges.

	2. Device attributes
	====================

	Accelerometer measurements are always provided.

	Temperature data are also provided. This data can be used to monitor the
	internal system temperature or to improve the temperature stability of the
	device via calibration.

	Each IIO device, has a device folder under ``/sys/bus/iio/devices/iio:deviceX``,
	where X is the IIO index of the device. Under these folders reside a set of
	device files, depending on the characteristics and features of the hardware
	device in questions. These files are consistently generalized and documented in
	the IIO ABI documentation.

	The following tables show the adxl380 related device files, found in the
	specific device folder path ``/sys/bus/iio/devices/iio:deviceX``.

	+---------------------------------------------------+----------------------------------------------------------+
	\| 3-Axis Accelerometer related device files \| Description \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_scale \| Scale for the accelerometer channels. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_filter_high_pass_3db_frequency \| Low pass filter bandwidth. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_filter_high_pass_3db_frequency_available \| Available low pass filter bandwidth configurations. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_filter_low_pass_3db_frequency \| High pass filter bandwidth. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_filter_low_pass_3db_frequency_available \| Available high pass filter bandwidth configurations. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_x_calibbias \| Calibration offset for the X-axis accelerometer channel. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_x_raw \| Raw X-axis accelerometer channel value. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_y_calibbias \| y-axis acceleration offset correction \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_y_raw \| Raw Y-axis accelerometer channel value. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_z_calibbias \| Calibration offset for the Z-axis accelerometer channel. \|
	+---------------------------------------------------+----------------------------------------------------------+
	\| in_accel_z_raw \| Raw Z-axis accelerometer channel value. \|
	+---------------------------------------------------+----------------------------------------------------------+

	+----------------------------------+--------------------------------------------+
	\| Temperature sensor related files \| Description \|
	+----------------------------------+--------------------------------------------+
	\| in_temp_raw \| Raw temperature channel value. \|
	+----------------------------------+--------------------------------------------+
	\| in_temp_offset \| Offset for the temperature sensor channel. \|
	+----------------------------------+--------------------------------------------+
	\| in_temp_scale \| Scale for the temperature sensor channel. \|
	+----------------------------------+--------------------------------------------+

	+------------------------------+----------------------------------------------+
	\| Miscellaneous device files \| Description \|
	+------------------------------+----------------------------------------------+
	\| name \| Name of the IIO device. \|
	+------------------------------+----------------------------------------------+
	\| sampling_frequency \| Currently selected sample rate. \|
	+------------------------------+----------------------------------------------+
	\| sampling_frequency_available \| Available sampling frequency configurations. \|
	+------------------------------+----------------------------------------------+

	Channels processed values
	-------------------------

	A channel value can be read from its _raw attribute. The value returned is the
	raw value as reported by the devices. To get the processed value of the channel,
	apply the following formula:

	.. code-block:: bash

	processed value = (_raw + _offset) * _scale

	Where _offset and _scale are device attributes. If no _offset attribute is
	present, simply assume its value is 0.

	The adis16475 driver offers data for 2 types of channels, the table below shows
	the measurement units for the processed value, which are defined by the IIO
	framework:

	+-------------------------------------+---------------------------+
	\| Channel type \| Measurement unit \|
	+-------------------------------------+---------------------------+
	\| Acceleration on X, Y, and Z axis \| Meters per Second squared \|
	+-------------------------------------+---------------------------+
	\| Temperature \| Millidegrees Celsius \|
	+-------------------------------------+---------------------------+

	Usage examples
	--------------

	Show device name:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> cat name
	adxl382

	Show accelerometer channels value:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_raw
	-1771
	root:/sys/bus/iio/devices/iio:device0> cat in_accel_y_raw
	282
	root:/sys/bus/iio/devices/iio:device0> cat in_accel_z_raw
	-1523
	root:/sys/bus/iio/devices/iio:device0> cat in_accel_scale
	0.004903325

	- X-axis acceleration = in_accel_x_raw * in_accel_scale = −8.683788575 m/s^2
	- Y-axis acceleration = in_accel_y_raw * in_accel_scale = 1.38273765 m/s^2
	- Z-axis acceleration = in_accel_z_raw * in_accel_scale = -7.467763975 m/s^2

	Set calibration offset for accelerometer channels:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
	0

	root:/sys/bus/iio/devices/iio:device0> echo 50 > in_accel_x_calibbias
	root:/sys/bus/iio/devices/iio:device0> cat in_accel_x_calibbias
	50

	Set sampling frequency:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> cat sampling_frequency
	16000
	root:/sys/bus/iio/devices/iio:device0> cat sampling_frequency_available
	16000 32000 64000

	root:/sys/bus/iio/devices/iio:device0> echo 32000 > sampling_frequency
	root:/sys/bus/iio/devices/iio:device0> cat sampling_frequency
	32000

	Set low pass filter bandwidth for accelerometer channels:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency
	32000
	root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency_available
	32000 8000 4000 2000

	root:/sys/bus/iio/devices/iio:device0> echo 2000 > in_accel_filter_low_pass_3db_frequency
	root:/sys/bus/iio/devices/iio:device0> cat in_accel_filter_low_pass_3db_frequency
	2000

	3. Device buffers
	=================

	This driver supports IIO buffers.

	All devices support retrieving the raw acceleration and temperature measurements
	using buffers.

	Usage examples
	--------------

	Select channels for buffer read:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_x_en
	root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_y_en
	root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_accel_z_en
	root:/sys/bus/iio/devices/iio:device0> echo 1 > scan_elements/in_temp_en

	Set the number of samples to be stored in the buffer:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> echo 10 > buffer/length

	Enable buffer readings:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> echo 1 > buffer/enable

	Obtain buffered data:

	.. code-block:: bash

	root:/sys/bus/iio/devices/iio:device0> hexdump -C /dev/iio\:device0
	...
	002bc300 f7 e7 00 a8 fb c5 24 80 f7 e7 01 04 fb d6 24 80 \|......$.......$.\|
	002bc310 f7 f9 00 ab fb dc 24 80 f7 c3 00 b8 fb e2 24 80 \|......$.......$.\|
	002bc320 f7 fb 00 bb fb d1 24 80 f7 b1 00 5f fb d1 24 80 \|......$...._..$.\|
	002bc330 f7 c4 00 c6 fb a6 24 80 f7 a6 00 68 fb f1 24 80 \|......$....h..$.\|
	002bc340 f7 b8 00 a3 fb e7 24 80 f7 9a 00 b1 fb af 24 80 \|......$.......$.\|
	002bc350 f7 b1 00 67 fb ee 24 80 f7 96 00 be fb 92 24 80 \|...g..$.......$.\|
	002bc360 f7 ab 00 7a fc 1b 24 80 f7 b6 00 ae fb 76 24 80 \|...z..$......v$.\|
	002bc370 f7 ce 00 a3 fc 02 24 80 f7 c0 00 be fb 8b 24 80 \|......$.......$.\|
	002bc380 f7 c3 00 93 fb d0 24 80 f7 ce 00 d8 fb c8 24 80 \|......$.......$.\|
	002bc390 f7 bd 00 c0 fb 82 24 80 f8 00 00 e8 fb db 24 80 \|......$.......$.\|
	002bc3a0 f7 d8 00 d3 fb b4 24 80 f8 0b 00 e5 fb c3 24 80 \|......$.......$.\|
	002bc3b0 f7 eb 00 c8 fb 92 24 80 f7 e7 00 ea fb cb 24 80 \|......$.......$.\|
	002bc3c0 f7 fd 00 cb fb 94 24 80 f7 e3 00 f2 fb b8 24 80 \|......$.......$.\|
	...

	See ``Documentation/iio/iio_devbuf.rst`` for more information about how buffered
	data is structured.

	4. IIO Interfacing Tools
	========================

	See ``Documentation/iio/iio_tools.rst`` for the description of the available IIO
	interfacing tools.