read

R2026b

Read data from I2C bus

Syntax

out = read(dev,numBytes)

out = read(dev,numBytes,precision)

Description

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

out = read(dev,numBytes) returns data read from the I2C bus based on the number of bytes.

out = read(dev,numBytes,precision) also specifies the data precision.

Examples

Read Data from an I2C Device on Arduino Hardware

Create an Arduino object and attach an I2C device object to it.

a = arduino();

Use an address to create the I2C device connection.

dev = device(a,'I2CAddress','0x55');

Read data from the I2C device.

out = read(dev,1)

out = 
4

Specify Precision to Read Data from an I2C Device on Arduino Hardware

Create an Arduino object and attach an I2C device object to it.

a = arduino();

Use an address to create the I2C device connection.

dev = device(a,'I2CAddress','0x55');

Read data from the I2C device with the precision of uint16.

out = read(dev,1,'uint16')

out = 
4

Input Arguments

dev — I2C device connection

device object

I2C device connection, specified as a device object.

numBytes — Number of bytes to read

scalar

Number of bytes of data to read from the I2C device, specified as a scalar.

precision — Data precision

'uint8' (default) | 'int8' | 'uint16' | 'int16' | 'uint32' | 'int32' | 'uint64' | 'int64'

Data precision, specified as one of the following character vectors:

• 'uint8'

• 'int8'

• 'uint16'

• 'int16'

• 'uint32'

• 'int32'

• 'uint64'

• 'int64'

Output Arguments

out — Value of data

scalar | vector

Value of data stored at the I2C device register, returned as a scalar or vector based on the precision.

More About

Code Generation Using MATLAB Function Block

• Use read in a MATLAB^® Function block with the Simulink^® Support Package for Arduino^® Hardware to generate code that can be deployed on Arduino Hardware.

Alternative Functionality

App

Use Arduino Explorer to configure the I2C peripherals and read data from I2C bus. You can use the app in the installed version of MATLAB and MATLAB Online™. For more information, see Connect to I2C Device Using Arduino Explorer App.

Version History

Introduced in R2014b