code: @SuppressWarnings("WeakerAccess")
      public ByteBuffer getRawData() {
          if (rawData != null) {
              rawData.rewind();
              return rawData.slice();
          }
          return null;
      }
docs: Get the raw bytes of the beat grid as it was read over the network. This can be used to analyze fields
  that have not yet been reliably understood, and is also used for storing the beat grid in a cache file.
  This is not available when the beat grid was loaded by Crate Digger.
  
  @return the bytes that make up the beat grid