def write_data_chunksize
      p = FFI::MemoryPointer.new(:uint, 1)
      check_result(Ftdi.ftdi_write_data_get_chunksize(ctx, p))
      p.read_uint
    end
def write_data_chunksize
      p = FFI::MemoryPointer.new(:uint, 1)
      check_result(Ftdi.ftdi_write_data_get_chunksize(ctx, p))
      p.read_uint
    end
Gets write buffer chunk size.
 @return [Fixnum] Write buffer chunk size.
 @raise [StatusCodeError] libftdi reports error.
 @see #write_data_chunksize=