https://itmanual.net/lg-%ec%9c%a0%ed%94%8c%eb%9f%ac%ec%8a%a4-%ea%b3%b5%ec%9c%a0%ea%b8%b0-%ec%b4%88%ea%b8%b0%ed%99%94-%eb%a6%ac%ec%85%8b-%eb%b9%84%eb%b0%80%eb%b2%88%ed%98%b8-%ec%b0%be%ea%b8%b0/