def output_messages(messages)
      if @output.nil?
        logger.error "trying to write to device that's not been initialized for output"
        raise NoOutputAllowedError
      end
      logger.debug "writing messages to launchpad:\n  #{messages.join("\n  ")}" if logger.debug?
      @output.write(messages)
      nil
    end
def output_messages(messages)
      if @output.nil?
        logger.error "trying to write to device that's not been initialized for output"
        raise NoOutputAllowedError
      end
      logger.debug "writing messages to launchpad:\n  #{messages.join("\n  ")}" if logger.debug?
      @output.write(messages)
      nil
    end
Writes several messages to the MIDI device.

 Parameters:

 [+messages+]  an array of hashes (usually created with message) with:
               [<tt>:message</tt>]   an array of
                                     MIDI status code,
                                     MIDI data 1 (note),
                                     MIDI data 2 (velocity)
               [<tt>:timestamp</tt>] integer indicating the time when the MIDI message was created