enableSerialPort

Enable serial interface

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

Syntax

enableSerialPort(bbb, port)

Description

enableSerialPort(bbb, port) enables the indicated port and configures the GPIO pins for use as serial (UART) pins. After the hardware starts, the serial ports are disabled by default.

For example, on a BeagleBone® Black Rev 00C0 board, enableSerialPort(bbb, 1) makes P9_24 (UART1_TX) and P8_26 (UART1_RX) available for use as serial pins.

To disable the serial interface, restart the hardware.

example

Examples

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You can connect to a serial device from the MATLAB® software, write data to the device, and read data from the device.

Create a connection from the MATLAB software to the BeagleBone Black hardware.

bbb = beaglebone

Enable serial port 1.

enableSerialPort(bbb,1)
bbb.AvailableSerialPorts
ans = 

    '/dev/ttyO1'

In '/dev/ttyO1', the 'O' is the capital letter O, not the number zero.

Show the location of the port 1 TX and RX pins, P9_24 (UART1_TXD) and P9_26 (UART1_RXD), on the GPIO header.

showPins(bbb)

The BeagleBone Black board uses +3.3 V. Do not connect BeagleBone Black hardware directly to devices that use higher voltages.

Connect the BeagleBone Black serial port to a +3.3 V serial device.

  • To receive data, connect the P9_26 (UART1_RXD) pin on the BeagleBone Black hardware to the TxD pin on the serial device.

  • To transmit data, connect the P9_24 (UART1_TXD) pin on the BeagleBone Black hardware to the RxD pin on the serial device.

  • To provide power, connect one of the +3.3 V pins on the BeagleBone Black hardware to the VCC pin on the serial device.

  • To ground the serial device, connect a ground pin (GND) on the BeagleBone Black hardware to the GND pin on the serial device.

Research the values the serial device requires for baud, data bits, parity, and stop bit.

Create a connection, serial, from the MATLAB software to the serial device.

serial = serialdev(bbb,'/dev/ttyO1',9600)
serial = 

  Serialdev with Properties:

    BaudRate: 9600
    DataBits: 8
      Parity: 'none'
    StopBits: 1
     Timeout: 10

Write a pair of values to a serial device that requires a specific data type.

write(serial,[10 12],'uint16')

Read a 100-element array of numbers from the serial port.

output = read(serial,100,'uint16')

Increase the timeout period of the serial port.

serial.Timeout = 20
serial = 

  Serialdev with Properties:

    BaudRate: 115200
    DataBits: 8
      Parity: 'none'
    StopBits: 1
     Timeout: 20

Input Arguments

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BeagleBone Black connection created using beaglebone, specified as an object.

Identifies port to enable.

Port 5 shares pins with HDMI, which is enabled by default. Use showPins to view the current pin usage. If HDMI is enabled, you cannot enable port 5 using enableSerialPort. For information on how to disable HDMI, see the BeagleBone Black hardware documentation.

Example: 1

Version History

Introduced in R2015a

See Also

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