eoeandroid第16期的文档，主要的内容是android的底层驱动开发和用户层的软件调用的方法，即应用软件通过调用API实现通过控制驱动程序控制IO口。-eoeandroid section 16 of the document, the contents of the main underlying driver of android software development and user-level method calls that applications by calling the API to implement the driver control by controlling the IO port.