def write_multiple_registers(addr, vals)
      s_val = ""
      vals.each do |reg|
        s_val << reg.to_word
      end

      query("\x10" + addr.to_word + vals.size.to_word + (vals.size * 2).chr + s_val)
      self
    end
def write_multiple_registers(addr, vals)
      s_val = ""
      vals.each do |reg|
        s_val << reg.to_word
      end

      query("\x10" + addr.to_word + vals.size.to_word + (vals.size * 2).chr + s_val)
      self
    end
Write multiple holding registers

 @example
  write_multiple_registers(1, [0xaa, 0]) => self

 @param [Integer] addr address first registers
 @param [Array] val written registers
 @return self