9f85a70a04
Docs now start at a high level, discussing sensors, attributes, channels, and reading data from them. Followed by more detailed usage guides in how to solve common problems sensor users may run into. Additionally renames the sensor_api sphinx tag to sensor Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
39 lines
1.4 KiB
ReStructuredText
39 lines
1.4 KiB
ReStructuredText
.. _sensor-attribute:
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Sensor Attributes
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#################
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:dfn:`Attributes`, enumerated in :c:enum:`sensor_attribute`, are immutable and
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mutable properties of a sensor and its channels.
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Attributes allow for obtaining metadata and changing configuration of a sensor.
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Common configuration parameters like channel scale, sampling frequency, adjusting
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channel offsets, signal filtering, power modes, on chip buffers, and event
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handling options are very common. Attributes provide a flexible API for
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inspecting and manipulating such device properties.
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Attributes are specified using :c:enum:`sensor_attribute` which can be used with
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:c:func:`sensor_attr_get` and :c:func:`sensor_attr_set` to get and set a sensors
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attributes.
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A quick example...
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.. code-block:: c
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const struct device *accel_dev = DEVICE_DT_GET(DT_ALIAS(accel0));
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struct sensor_value accel_sample_rate;
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int rc;
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rc = sensor_attr_get(accel_dev, SENSOR_CHAN_ACCEL_XYZ, SENSOR_ATTR_SAMPLING_FREQUENCY, &accel_sample_rate);
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if (rc != 0) {
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printk("Failed to get sampling frequency\n");
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}
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printk("Sample rate for accel %p is %d.06%d\n", accel_dev, accel_sample_rate.val1, accel_sample_rate.val2*1000000);
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accel_sample_rate.val1 = 2000;
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rc = sensor_attr_set(accel_dev, SENSOR_CHAN_ACCEL_XYZ, SENSOR_ATTR_SAMPLING_FREQUENCY, accel_sample_rate);
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if (rc != 0) {
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printk("Failed to set sampling frequency\n");
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}
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