# File lib/rqrcode/qrcode/qr_alphanumeric.rb, line 29
    def write( buffer)
      buffer.alphanumeric_encoding_start(get_length)

      (@data.size).times do |i|
        if i % 2 == 0
          if i == (@data.size - 1)
            value = ALPHANUMERIC.index(@data[i])
            buffer.put( value, 6 )
          else
            value = (ALPHANUMERIC.index(@data[i]) * 45) + ALPHANUMERIC.index(@data[i+1])
            buffer.put( value, 11 )
          end
        end
      end


    end