device

Connection to device on I2C bus on Arduino or ESP32 hardware

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

Description

This object represents a connection to the I2C device on Arduino^® or ESP32 hardware. Attach an I2C device to the appropriate pins on the Arduino or ESP32 hardware. You can interact with the I2C device using the functions listed in Object Functions.

Creation

Syntax

deviceObj = device(arduinoObj,'I2CAddress',I2CAddress,Name,Value)

Description

deviceObj = device(arduinoObj,'I2CAddress',I2CAddress,Name,Value) creates an object that represents the connection between an I2C peripheral connected to the central Arduino or ESP32 hardware. The Arduino or ESP32 hardware is represented by an arduino object. You can also customize the connection further using one or more name-value pairs. The 'I2CAddress' name-value pair is mandatory for creating the I2C device connection.

example

Input Arguments

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`arduinoObj` — Arduino or ESP32 hardware connection
`arduino` object

Arduino or ESP32 hardware connection created using arduino, specified as an arduino object.

Name-Value Arguments

Specify at least one comma-separated pair of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN

Example: deviceObj = device(arduinoObj,'I2CAddress','0x71');

`I2CAddress` — Address of I2C device
character vector | string | integer scalar | hexadecimal | binary

This is a mandatory name value pair argument if you are connecting to an I2C device. Address of the I2C device connected to the I2C bus, specified as a character vector, string, or integer. The address can be a hex or a scalar integer. Obtain this address value using the scanI2CBus function.

Example: deviceObj = device(arduinoObj,'I2CAddress','0x68')

`Bus` — I2C bus number
`0` (default) | `1`

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

Note

Bus number 1 is only available on Due and Nano33BLE boards. Other Arduino boards support Bus number 0.

Example: deviceObj = device(arduinoObj,'I2CAddress','0x61','bus',0) creates a connection to the I2C bus on the hardware.

`BitRate` — Maximum speed of I2C communication
`100000` (default) | `400000`

The maximum speed of I2C communication in bits/s, specified as 100000 or 400000 bits/s.

Example: deviceObj = device(arduinoObj,'I2CAddress','0x71','bitrate',100000) creates a connection to the I2C device and sets the bitrate to 100000 bits/s.

Data Types: double

Properties

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`Interface` — Type of interface used for communication
`'I2C'`

This property is read-only.

Specifies the type of interface used for communication.

Example:

>> deviceObj.Interface
ans = 
      I2C

`I2CAddress` — Address of I2C device
numeric

This property is read-only.

I2C device address on the Arduino hardware, specified as a number.

Example:

>> deviceObj.I2CAddress
ans = 
      104

Data Types: double

`Bus` — I2C bus number
`0` (default) | 1

This property is read-only.

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

Note

Only Arduino Due board supports both the I2C bus numbers 0 and 1.

Example:

>> deviceObj.Bus
ans = 
      0

Data Types: double

`SCLPin` — Serial clock pin
character vector

This property is read-only.

This property is read-only. A serial clock pin for the serial clock signal that the I2C central generates.

Note

SCLPin for I2CBus1 appears as SCL1.

Example:

>> deviceObj.SCLPin
ans = 
      'A5'

Data Types: char

`SDAPin` — Serial data pin
character vector

This property is read-only. A serial data pin for a serial data signal.

Note

SDAPin for I2CBus1 appears as SDA1.

Example:

>> deviceObj.SDAPin
ans = 
      'A4'

Data Types: char

`BitRate` — Speed at which bus is set for I2C communication
`100000` | positive integer

This property is read-only.

The speed at which bus is set for I2C communication, specified as a positive integer in bits/s.

Example:

>> deviceObj.BitRate
ans = 
      100000

Data Types: double

Object Functions

`read`	Read data from I2C bus
`readRegister`	Read data from I2C device register
`write`	Write data to I2C bus
`writeRegister`	Write data to I2C device register

Examples

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Create I2C Device Connection

This example uses:

MATLAB Support Package for Arduino Hardware MATLAB Support Package for Arduino Hardware

Open Live Script

Create an arduino object with I2C library.

arduinoObj = arduino("COM15","Uno","Libraries","I2C")

arduinoObj = 
  arduino with properties:

                  Port: 'COM15'
                 Board: 'Uno'
         AvailablePins: {'D2-D13', 'A0-A5'}
  AvailableDigitalPins: {'D2-D13', 'A0-A5'}
      AvailablePWMPins: {'D3', 'D5-D6', 'D9-D11'}
   AvailableAnalogPins: {'A0-A5'}
    AvailableI2CBusIDs: [0]
             Libraries: {'I2C'}
Show all properties

Create a device object.

deviceObj = device(arduinoObj,'I2CAddress','0x50')

deviceObj = 
  device with properties:

             Interface: 'I2C'
            I2CAddress: 80 ('0x50')
                   Bus: 0
                SCLPin: 'A5'
                SDAPin: 'A4'
               BitRate: 100000 (bits/s)

Show functions

More About

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Code Generation Using MATLAB Function Block

Use device in a MATLAB^® Function block with the Simulink^® Support Package for Arduino Hardware to generate code that can be deployed on Arduino Hardware.
Specifying BitRate as a name value pair argument is not supported the in MATLAB Function block. You can set BitRate from the Configuration Parameters dialog box. To set the BitRate:
- On the Simulink Toolstrip, in the Hardware tab, click Hardware Settings to open the Configuration Parameters dialog box.
- In the Configuration Parameters dialog box, select Hardware Implementation. Verify that the Hardware board parameter is set to the appropriate Arduino board.
- Go to Hardware board settings > Target hardware resources > I2C properties.
- Enter the value to set BitRate in I2C Bus Speed(Hz).
The properties Interface, BitRate, SCLPin, and SDAPin are not accessible from the device object.

Version History

Introduced in R2019a

device

Description

Creation

Syntax

Description

Input Arguments

arduinoObj — Arduino or ESP32 hardware connection arduino object

I2CAddress — Address of I2C device character vector | string | integer scalar | hexadecimal | binary

Bus — I2C bus number 0 (default) | 1

BitRate — Maximum speed of I2C communication 100000 (default) | 400000

Properties

Interface — Type of interface used for communication 'I2C'

I2CAddress — Address of I2C device numeric

Bus — I2C bus number 0 (default) | 1

SCLPin — Serial clock pin character vector

SDAPin — Serial data pin character vector

BitRate — Speed at which bus is set for I2C communication 100000 | positive integer

Object Functions

Examples

Create I2C Device Connection

More About

Code Generation Using MATLAB Function Block

Version History

See Also

`arduinoObj` — Arduino or ESP32 hardware connection
`arduino` object

`I2CAddress` — Address of I2C device
character vector | string | integer scalar | hexadecimal | binary

`Bus` — I2C bus number
`0` (default) | `1`

`BitRate` — Maximum speed of I2C communication
`100000` (default) | `400000`

`Interface` — Type of interface used for communication
`'I2C'`

`I2CAddress` — Address of I2C device
numeric

`Bus` — I2C bus number
`0` (default) | 1

`SCLPin` — Serial clock pin
character vector

`SDAPin` — Serial data pin
character vector

`BitRate` — Speed at which bus is set for I2C communication
`100000` | positive integer