https://blog.wongcw.com/2019/12/17/%e5%87%b1%e4%bf%a0%e7%99%bc%e5%b8%83twin-bics%e6%96%b0%e6%8a%80%e8%a1%93plc%e9%96%83%e5%ad%98%e8%b6%8a%e4%be%86%e8%b6%8a%e8%bf%91%e4%ba%86/