https://blog.wongcw.com/2020/06/28/qlc%e3%80%81plc%e9%96%83%e5%ad%98%e5%a3%bd%e5%91%bd%e6%9c%89%e5%a4%9a%e9%9b%a3%e7%9c%8b%ef%bc%9f%e6%9c%80%e5%bf%ab35%e6%ac%a1%e5%af%ab%e5%ae%8c/