USB: USB connection.
Functions

nil usb.on ()
  Enable usb driver.

nil usb.off ()
  Disable usb driver.

usb.status boolean ()
  USB driver status.

usb.state table ()
  Determines the status of the connection to the USB.
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Function Documentation

nil usb.on ()
  Enable usb driver.
  Returns:
  Nothing.

nil usb.off ()
  Disable usb driver.
  Returns:
  Nothing.

usb.status boolean ()
  USB driver status.
  Being activated means that if you connect the USB cable, the connection is established, but does not mean it is actually connected.
  Returns:
  Usb status.
  Exceptions:
  - Even returning true, maybe the usb is not connected, see usb :: state ().

usb.state table ()
  Determines the status of the connection to the USB.
  To see if the USB connection has been established will use the "established".
  Returns:
  A table with the following fields: "activated", "connected" and "established". All Boolean value.