105 lines
3.3 KiB
ReStructuredText
105 lines
3.3 KiB
ReStructuredText
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.. _adxl372:
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ADXL372: Three Axis High-g I2C/SPI Accelerometer
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################################################
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Description
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***********
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This sample application produces slightly different outputs based on the chosen
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driver configuration mode:
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* In **Measuring Mode with trigger support**,
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the acceleration on all three axis is printed in m/s^2 at the sampling rate (ODR).
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* In **Polled Measuring Mode**, the instantaneous acceleration is polled every 2 seconds.
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* In **Max Peak Detect Mode**, the device returns only the over-threshold
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peak acceleration between two consecutive sample fetches or trigger events.
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(In most high-g applications, a single 3-axis acceleration sample at the peak
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of an impact event contains sufficient information about the event, and the
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full acceleration history is not required.) Instead of printing the acceleration
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on all three axis, the sample application calculates the vector magnitude
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(root sum squared) and displays the result in g's rather than in m/s^2,
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together with an bar graph.
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References
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**********
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- ADXL372: http://www.analog.com/adxl372
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Wiring
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*******
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This sample uses the ADXL372 sensor controlled either using the I2C or SPI interface.
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Connect supply **VDD**, **VS** and **GND**. The supply voltage can be in
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the 1.6V to 3.5V range.
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I2C mode
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========
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Connect Interface: **SDA**, **SCL** and optionally connect the **INT1** to a
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interrupt capable GPIO. It is a requirement that **SCLK** must be connected to
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**GND** in I2C mode. Depending on the baseboard used, the **SDA** and **SCL**
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lines require Pull-Up resistors. With the **MISO** pin low, the I2C address for
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the device is 0x1D, and an alternate I2C address of 0x53 can be chosen by
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pulling the **MISO** pin high.
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I2C Address:
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* **0x1D**: if MISO is pulled low
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* **0x53**: if MISO is pulled high
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.. Note::
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When sharing an SDA bus, the ADXL372 Silicon Revision < 3 may prevent
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communication with other devices on that bus.
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SPI mode
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========
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Connect Interface: **SCLK**, **MISO**, **MOSI** and **/CS** and optionally
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connect the **INT1** to a interrupt capable GPIO.
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Building and Running
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********************
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This project outputs sensor data to the console. It requires an ADXL372
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sensor. It should work with any platform featuring a I2C/SPI peripheral interface.
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It does not work on QEMU.
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In this example below the :ref:`nrf52_pca10040` board is used.
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.. zephyr-app-commands::
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:zephyr-app: samples/sensors/adxl372
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:board: nrf52_pca10040
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:goals: build flash
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Sample Output: Max Peak Detect Mode
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===================================
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.. code-block:: console
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Waiting for a threshold event
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23.94 g: ########################
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Waiting for a threshold event
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38.01 g: #######################################
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Waiting for a threshold event
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51.40 g: ####################################################
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Waiting for a threshold event
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63.63 g: ################################################################
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Sample Output: Measurement Mode
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===============================
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.. code-block:: console
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AX= 2.94 AY= -5.88 AZ= 0.98 (m/s^2)
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AX= -4.90 AY= 6.86 AZ= -1.96 (m/s^2)
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AX= 2.94 AY= -2.94 AZ= 8.83 (m/s^2)
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AX= -0.98 AY= -6.86 AZ= -0.98 (m/s^2)
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AX= 6.86 AY= 2.94 AZ= 3.92 (m/s^2)
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AX= -0.98 AY= 4.90 AZ= -3.92 (m/s^2)
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<repeats endlessly>
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