====== ReadDistanceSensor ======

The **ReadDistanceSensor** function reads the distance measured by the ultrasonic sensor in centimeters.

The **input** parameter should be an NXT input port number between 1 and 4 (which the ultrasonic sensor is plugged into).
<code>dist = nxt.ReadDistanceSensor( input );</code>


====Example - Read distance sensor on port 4====
<code javascript>
function OnStart()
{
  nxt = app.CreateNxt();
  app.SetMenu( "Connect,Distance" );
}

function OnMenu( name )
{
  if( name=="Connect" )
    nxt.ShowDevices();

  else if( name=="Distance" )
  {
    dist = nxt.ReadDistanceSensor( 4 );
    app.ShowPopup( dist + " cm" );
  }
}
</code>