利用双串口控制投影仪开关机等一些基本功能-controls the projecting apparatus

启明星办公用品采购系统，可以帮助行政部管理日常的办公用品，诸如记事本、纸张、橡皮、文件夹等同时还具有大件管理功能，诸如打印机、投影仪、墨盒等。-The Venus office supplies procurement system can help the Administration Department manage the day-to-day office supplies, such as Notepad, paper, erasers, folders, etc. It also

投影仪安装位置计算，根据投影的投射比例和ZOOM比，计算投影的安装位置-Projector mounting position, according to the projection throw ratio and ZOOM ratio, calculated projection installation location