device

Connection to device on SPI 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 SPI device on Arduino^® or ESP32 hardware. Attach an SPI device to the appropriate pins on the Arduino or ESP32 hardware. You can interact with the SPI device using the functions listed in Object Functions.

Creation

Syntax

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

Description

deviceObj = device(arduinoObj,'SPIChipSelectPin',SPIChipSelectPin,Name,Value) creates an object that represents the connection between SPI device connected to the SPI bus on the 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 'SPIChipSelectPin' name-value pair is mandatory for creating the SPI 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,'SPIChipSelectPin','D8');

`SPIChipSelectPin` — Chip select pin number for SPI communication
character vector | string

This is a mandatory name value pair argument if you are connecting to an SPI device. Represents pin number that is used as the chip select pin on the Arduino hardware to communicate with the SPI device.

To identify the pins that can be used as chip select pins, see Chip Select Pins.

Example: deviceObj = device(arduinoObj,'SPIChipSelectPin','D10')

`SPIMode` — SPI communication mode
`0` (default) | `1` | `2` | `3`

SPI communication mode, specified as a number between 0 and 3. Specify the clock polarity and phase by setting the mode.

SPI Mode	Clock Polarity	Clock Phase
0	0	0
1	0	1
2	1	0
3	1	1

Example: deviceObj = device(arduinoObj,'SPIChipSelectPin','D4','SPIMode',3) creates a connection to the SPI device and sets the clock polarity to 1 and clock phase to 1.

`BitOrder` — SPI communication bit order
`'msbfirst'` (default) | `'lsbfirst'`

SPI communication bit order, specified as:

'msbfirst' - The most significant bit is transmitted first.
'lsbfirst' - The least significant bit is transmitted first.

Example: deviceObj = device(arduinoObj,'SPIChipSelectPin','D4','bitorder','lsbfirst') creates a connection to the SPI device and sets the least significant bit in the first column.

`BitRate` — Maximum speed of SPI communication
`4000000` (default) | positive integer

The maximum speed of SPI communication in bits/s, specified as a positive integer.

Example: deviceObj = device(arduinoObj,'SPIChipSelectPin','D4','bitrate',2000000) creates a connection to the SPI device and sets the bitrate to 2000000 bits/s.

Properties

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

This property is read-only.

Specifies the type of interface used for communication.

Example:

>> d.Interface

ans = 

  InterfaceEnum enumeration

    Serial

`SPIChipSelectPin` — Chip select pin for SPI communication
character vector

This property is read-only.

Arduino pin connected to chip select line on the SPI device, specified as a character vector of the form 'Ax' or 'Dx'. Here, x is the pin number, D is digital, and A is analog.

To identify the pins that can be used as chip select pins, see Chip Select Pins.

Example:

>> deviceObj.SPIChipSelectPin
ans = 
      'D10'

Data Types: char

`SCLPin` — Serial clock pin
character vector

This property is read-only.

A serial clock pin for the serial clock signal that the SPI controller generates.

Example:

>> deviceObj.SCLPin

ans =

     'D13'

Data Types: char

`SDIPin` — Serial Data In pin
character vector

This property is read-only.

The pin that connects the peripheral output to the controller input.

Example:

>> deviceObj.SDIPin

ans =

     'D12'

Data Types: char

`SDOPin` — Serial Data Out pin
character vector

This property is read-only.

The pin that connects the controller output to the peripheral input.

Example:

>> deviceObj.SDOPin

ans =

     'D11'

Data Types: char

`SPIMode` — SPI communication mode
`0` (default) | `1` | `2` | `3`

SPI communication mode, specified as a number between 0 and 3. Specify the clock polarity and phase by setting the mode.

SPI Mode	Clock Polarity	Clock Phase
0	0	0
1	0	1
2	1	0
3	1	1

Example:

>> deviceObj.SPIMode

ans =

     2

Data Types: double

`ActiveLevel` — Logic level
`'low'` (default) | `'high'`

This property is read-only.

The logic levels of the SPI pins.

Example:

>> deviceObj.ActiveLevel

ans =
    ActiveLevelEnum enumeration 
    low

`BitOrder` — SPI communication bit order
`'msbfirst'` (default) | `'lsbfirst'`

SPI communication bit order, specified as msbfirst or lsbfirst. If it is msbfirst, the most significant bit is transmitted first to the writeRead output. If it is lsbfirst, the least significant bit is transmitted first.

Example:

>> deviceObj.BitOrder

ans = 

    'msbfirst'

`BitRate` — Speed at which bus is set for SPI communication
`4000000` (default) | positive integer

This property is read-only.

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

Example:

>> deviceObj.BitRate

ans = 

    4000000

Data Types: double

Object Functions

writeRead Write and read data from SPI device

Examples

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Create SPI 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 the SPI library.

arduinoObj = arduino('COM5','Uno','Libraries','SPI')

arduinoObj = 
  arduino with properties:

                  Port: 'COM5'
                 Board: 'Uno'
         AvailablePins: {'D2-D13', 'A0-A5'}
  AvailableDigitalPins: {'D2-D13', 'A0-A5'}
      AvailablePWMPins: {'D3', 'D5-D6', 'D9-D11'}
   AvailableAnalogPins: {'A0-A5'}
    AvailableI2CBusIDs: [0]
             Libraries: {'SPI'}
Show all properties

Create a device object.

deviceObj = device(arduinoObj,'SPIChipSelectPin','D10')

deviceObj = 
  device with properties:

             Interface: 'SPI'
      SPIChipSelectPin: 'D10'
                SCLPin: 'D13'
                SDIPin: 'D12'
                SDOPin: 'D11'

Show all properties, 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 SPIMode,BitRate, and BitOrder as name-value pair arguments is not supported in the MATLAB Function block. You can set SPIMode,BitRate, and BitOrder from the Configuration Parameters dialog box. To set the values:
- 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 > SPI properties.
- Enter the value to set BitRate in SPI clock out frequency(kHz), SPIMode, and BitOrder.
The properties Interface,SPIMode, BitRate,BitOrder,SCLPin,SDIPin, and SDOPin are not accessible from the device object.
The property ActiveLevel is always 'low'.

Version History

Introduced in R2019a

device

Description

Creation

Syntax

Description

Input Arguments

arduinoObj — Arduino or ESP32 hardware connection arduino object

SPIChipSelectPin — Chip select pin number for SPI communication character vector | string

SPIMode — SPI communication mode 0 (default) | 1 | 2 | 3

BitOrder — SPI communication bit order 'msbfirst' (default) | 'lsbfirst'

BitRate — Maximum speed of SPI communication 4000000 (default) | positive integer

Properties

Interface — Type of interface used for communication 'SPI'

SPIChipSelectPin — Chip select pin for SPI communication character vector

SCLPin — Serial clock pin character vector

SDIPin — Serial Data In pin character vector

SDOPin — Serial Data Out pin character vector

SPIMode — SPI communication mode 0 (default) | 1 | 2 | 3

ActiveLevel — Logic level 'low' (default) | 'high'

BitOrder — SPI communication bit order 'msbfirst' (default) | 'lsbfirst'

BitRate — Speed at which bus is set for SPI communication 4000000 (default) | positive integer

Object Functions

Examples

Create SPI Device Connection

More About

Code Generation Using MATLAB Function Block

Version History

See Also

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

`SPIChipSelectPin` — Chip select pin number for SPI communication
character vector | string

`SPIMode` — SPI communication mode
`0` (default) | `1` | `2` | `3`

`BitOrder` — SPI communication bit order
`'msbfirst'` (default) | `'lsbfirst'`

`BitRate` — Maximum speed of SPI communication
`4000000` (default) | positive integer

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

`SPIChipSelectPin` — Chip select pin for SPI communication
character vector

`SCLPin` — Serial clock pin
character vector

`SDIPin` — Serial Data In pin
character vector

`SDOPin` — Serial Data Out pin
character vector

`SPIMode` — SPI communication mode
`0` (default) | `1` | `2` | `3`

`ActiveLevel` — Logic level
`'low'` (default) | `'high'`

`BitOrder` — SPI communication bit order
`'msbfirst'` (default) | `'lsbfirst'`

`BitRate` — Speed at which bus is set for SPI communication
`4000000` (default) | positive integer