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lsm6dsl

Connection to LSM6DSL sensor on Arduino hardware I2C bus

Since R2021a

    Add-On Required: This feature requires the MATLAB Support Package for Arduino Hardware add-on.

    Description

    The lsm6dsl object reads acceleration, angular velocity, and temperature using the LSM6DSL sensor connected to the I2C bus of the hardware. The LSM6DSL is an inertial measurement unit (IMU) used to read acceleration and angular velocity in all three dimensions. The LSM6DSL also has an embedded temperature sensor. Attach an LSM6DSL sensor to the I2C pins on the hardware. You can read the data from your sensor in MATLAB® using the Object Functions.

    Creation

    Description

    imu = lsm6dsl(a) creates a sensor object with default property values.

    Example: imu = lsm6dsl(a);.

    imu = lsm6dsl(a,Name,Value) creates a sensor object with properties using one or more Name,Value pair arguments.

    Example: imu = lsm6dsl(a,'I2CAddress',0x6A);.

    Input Arguments

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    Connection to the hardware specified as an object.

    Example: imu = lsm6dsl(a) creates a connection to the LSM6DSL sensor on the hardware represented as an object, a.

    Name-Value Arguments

    Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

    Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

    Specify the I2C address of the sensors when multiple I2C devices with the expected address for LSM6DSL are connected to the same hardware board. LSM6DSL can have two I2C addresses depending on the logic level on pin SDO/SA0 of the sensor.

    Pin NamePin StateI2C Address
    SDO/SA0Low0x6A
    High0x6B

    You can specify the I2C address in:

    • Hexadecimal, decimal, or binary format

    • String of hexadecimal value of I2C Address

    • Character vector of hexadecimal value of I2C Address

    Example: imu = lsm6dsl(a,'I2CAddress',0x6A)

    0x6A is the I2C address of the accelerometer and gyroscope of LSM6DSL connected to Arduino board.

    If not specified, the object will be created with one of the available I2C device address in the table. Availability of I2C device with the expected address will be determined by using scanI2CBus.

    I2C bus number, specified as 0 or 1. The default value is 0.

    Example: imu = lsm6dsl(a, 'Bus', 1) creates the sensor object on Bus 1 of the hardware.

    Data Types: double

    Properties

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    Note

    The properties can also be used as name-value pair arguments while creating an lsm6dsl object.

    Specify the I2C address of the sensors when multiple I2C devices with the expected address for LSM6DSL are connected to the same hardware board. LSM6DSL can have two I2C addresses depending on the logic level on pin SDO/SA0 of the sensor.

    Pin NamePin StateI2C Address
    SDO/SA0Low0x6A
    High0x6B

    You can specify the I2C address in:

    • Hexadecimal, decimal, or binary format

    • String of hexadecimal value of I2C Address

    • Character vector of hexadecimal value of I2C Address

    0x6A is the I2C address of the accelerometer and gyroscope of LSM6DSL connected to Arduino board.

    If not specified, the object will be created with one of the available I2C device address in the table. Availability of I2C device with the expected address will be determined by using scanI2CBus.

    I2C bus number, specified as 0 or 1. The default value is 0.

    Data Types: double

    Note

    Except for TimeFormat, all the other properties are non-tunable, which means you cannot change their values once the object is locked. Objects are locked when you call the read function, and the release function unlocks them. If a property is tunable, you can change its value at any time.

    The rate in samples/s at which data is read from the sensor.

    Data Types: double

    Number of samples read from the sensor in a single execution of the read function.

    Data Types: double

    Specify whether to return the latest or the oldest data samples. The number of samples depends on the SamplesPerRead value. The data read from the sensor is stored in the MATLAB buffer.

    • latest

      Provides the latest data samples available in the buffer. All previous data samples in the buffer are discarded. For example, if SamplesPerRead = 3, the latest three data samples read by the sensor are returned.

      The following figure illustrates how latest data samples are returned assuming S1 is the first sensor data stored in the buffer, S2 is the second data and so on and Sn is the last data stored in the buffer and SamplesPerRead property is set to 3 during sensor object creation.

    • oldest

      Provides the oldest data samples available in the buffer. In this case, no data samples are discarded. For example, if SamplesPerRead = 3, the first three data samples read are returned for the first read, the next three data samples are returned for the second read, and so on.

      The following figure illustrates how oldest data samples are returned assuming S1 is the first sensor data stored in the buffer, S2 is the second data and so on and Sn is the last data stored in the buffer and SamplesPerRead property is set to 3 during sensor object creation.

    Data Types: character vector | string

    This property is read-only.

    Samplesread property outputs the values of samples read so far by executing read function. Samplesread is set to 0, when the object is created or when you release the object.

    Data Types: double

    This property is read-only.

    Samples available in the host buffer. The data read from the sensor is stored in the MATLAB buffer.SamplesAvailable property shows the number of SamplesAvailable in this host buffer. When you release the object, SamplesAvailable is set to 0. When the ReadMode of sensor is set as latest, SamplesAvailable will always be 0.

    Data Types: double

    Set the output format of the data returned by executing the read function.

    When the OutputFormat is set to timetable, the data returned has the following fields:

    • Time — Time stamps in datetime or duration format

    • Acceleration — N-by-3 array in units of m/s2

    • AngularVelocity — N-by-3 array in units of rad/s

    • Temperature — N-by-1 array in units of degree Celsius

    When the OutputFormat is set to matrix, the data is returned as matrices of acceleration, angular velocity, and time stamps. The units for the sensor readings are the same as the timetable format.

    N is the number of samples per read specified by SamplesPerRead. The three columns of each field represent the measurements in x, y, and z axes.

    Data Types: character vector | string

    Set the format of the time displayed when the sensor data is read.

    • datetime — Displays the date and time at which the data is read.

    • duration — Displays the time elapsed in seconds after the sensor object is locked. The sensor object gets locked at the first call of the read function either after the object creation or after the execution of the release function.

    Data Types: character vector | string

    Object Functions

    readAccelerationRead one sample of acceleration from sensor
    readAngularVelocityRead one sample of angular velocity from sensor
    readTemperatureRead one sample of temperature from sensor
    readRead real-time sensor data at a specified rate
    releaseRelease the sensor object
    flushFlush the host buffer
    infoRead information related to sensor

    Examples

    Create Connection to LSM6DSL Sensor

    Create an arduino object with the I2C library.

    a = arduino('COM4', 'Uno', 'Libraries', 'I2C');

    Create the sensor object.

    imu = lsm6dsl(a)
    imu = 
    
      lsm6dsl with properties: 
    
                     I2CAddress: 106  ("0x6B")
                         SCLPin: "A5" 
                         SDAPin: "A4" 
    
                     SampleRate: 100  (Samples/s)
                 SamplesPerRead: 10  
                       ReadMode: 'latest'            
                    SamplesRead: 0      
               SamplesAvailable: 0 
    Show all properties, functions
    

    Create LSM6DSL Sensor Connection with Additional Name-Value Pair Arguments

    Create a sensor object with additional properties specified as name-value pair arguments.

    clear imu;
    imu = lsm6dsl(a,'SampleRate',110,'SamplesPerRead',3,'ReadMode','oldest')
    imu =
    
      lsm6dsl with properties:
    
                             I2CAddress: 107 ("0x6B")
                                    Bus: 0
                                 SCLPin: "A5"
                                 SDAPin: "A4"
    
                             SampleRate: 110 (samples/s)
                         SamplesPerRead: 3
                               ReadMode: "oldest"
                            SamplesRead: 0
                       SamplesAvailable: 0
    
    Show all properties all functions

    More About

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    Version History

    Introduced in R2021a