readTemperature

Read one sample of temperature from sensor

Syntax

[tempReadings,timestamp] = readTemperature(sensorobj)

Description

[tempReadings,timestamp] = readTemperature(sensorobj) returns one sample of the temperature measured in degree Celsius along with the timestamp. Timestamp is optional.

Note

• The readTemperature function is available for the LSM6DS3, LSM6DS3H, LSM6DSL, LSM6DSM, LSM6DSR, LSM6DSO, LPS22HB, LSM303C, HTS221, ICM20948, ADXL345, and LIS3DH sensors.

• To generate C/C++ code for this function, you must have an Embedded Coder^® license.

Examples

Read Ambient Temperature Data from Sensor

Create a connection from MATLAB^® to the Raspberry Pi^® hardware board.

mypi = raspi('raspberrypi-hysdu8X38o','rocky','bullwinkle')

mypi = 

  Raspi with Properties:

           DeviceAddress: 'raspberrypi-hysdu8X38o'
                    Port: 18734
               BoardName: 'Raspberry Pi 3 Model B+'
           AvailableLEDs: {'led0'}
    AvailableDigitalPins: [4,5,6,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27]
    AvailableSPIChannels: {‘CE0’,’CE1’}
       AvailableI2CBuses: {'i2c-1'}
             I2CBusSpeed: 100000
        AvailabelWebCams: mmal service 16.1 (platform:bcm2835-v4l2)

Create a sensor object on the I2C bus 'i2c-1' on addresses '0x6B'.

Note

The sample code and output in this example is for lsm6dsl object. If you are using another sensor that supports readTemperature function, use the corresponding sensor object.

sensorobj = lsm6dsl(mypi,'Bus','i2c-1','I2CAddress','0x6B');

sensorobj = 

  lsm6dsl with properties:

                         I2CAddress: 107 ("0x6B")
                                Bus: i2c-1

Return one sample of ambient temperature data read from the sensor.

[tempReading,timestamp] = readTemperature(sensor);

tempReading =

  data

    15.3398

timestamp = 

  datetime

   5-Jan-2021 11:35:17.279

Since the timestamp output is optional, you can obtain only the ambient temperature data from the sensor.

[tempReading] = readTemperature(sensor);

tempReading =

  data

    15.3398

Input Arguments

sensorobj — sensor object

sensor object

The sensor object with the default or specified properties.

Output Arguments

tempReadings — Value read from the sensor

scalar

The temperature from the sensor.

timestamp — Timestamp

datetime

The time at which MATLAB receives temperature data from the sensor, specified as a datetime.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

• Timestamp value is always returned in seconds.

• When you create an lsm6dsl sensor object and do not specify the I2C address in the name-value pair, the default I2C address is considered by the sensor.

• To generate C/C++ code for this function, you must have an Embedded Coder license. For more information on selecting the right product stack according to your development goals, see Product Stack for Raspberry Pi Blockset.

Version History

Introduced in R2021a