Turn BeagleBone Black LED On and Off

This example shows how to turn an onboard LED on and off.

Create a connection to the BeagleBone^® Black hardware and assign the connection to an object, bbb.

bbb = beaglebone

bbb = 

  beaglebone with properties:

           DeviceAddress: '192.168.7.2'
               BoardName: 'BeagleBone Black Rev 00C0'
           AvailableLEDs: {'USR0'  'USR1'  'USR2'  'USR3'}
    AvailableDigitalPins: {1x29 cell}
     AvailableAnalogPins: {'AIN0'  'AIN1'  'AIN2'  'AIN3'  'AIN4'  'AIN5'  'AIN6'}
        AvailablePWMPins: {}
    AvailableSPIChannels: {}
       AvailableI2CBuses: {'i2c-1'}
    AvailableSerialPorts: {}
        AvailableWebcams: {}

The AvailableLEDs property shows the name of the user-controllable LED. To show the location of the user-controllable LED on the board, type:
```
showLEDs(bbb)
```
The figure shows the output of a call to showLEDs.
Turn the specified LED on by setting its value to 1 or true.
```
writeLED(bbb,'usr0',1)
```
Turn the LED off by setting its value to 0 or false.
```
writeLED(bbb,'usr0',false)
```

To restore LED 'usr0' to its default, which is to indicate Linux^® kernel activity, restart the BeagleBone Black hardware.