Design And Implementation Of Wi-Fi Module Over Android Platform

In recent years, with the rapid development of the Internet, the network has entered the household, production and life and become an indispensable source of information. People are not satisfied with sitting at a computer desk browsing the web, but to get online anytime, anywhere they want to access to information. In this context, Mobile Internet Devices (MID) become the new main battlefield of competition of major Internet companies.Routon Electronic Co., Ltd., Wuhan launched P760 car navigation terminal device is based on Samsung S3C6410 processor, using Google's Android operating system. In order to meet growing customer demand for Network, the product implemented Wi-Fi and other mobile Internet access. According to Android system hierarchy, Wi-Fi implementation work is divided into three parts, the device driver layer, middle layer and application layer.Device driver layer. Android system is based on Linux kernel, thus it uses Linux device drivers. Wi-Fi driver can be further subdivided into two layers, namely, I / O communication layer and the Wi-Fi functionality layer. Wi-Fi module uses the SPI bus , so I / O communication layer is equivalent to SPI bus driver. The driver of Wi-Fi functionality layer is provided by hardware manufacturerMiddle layer connects the device driver layer and the application layer. It includes Android hardware abstraction layer (HAL) interface and Wi-Fi supplicant program, which were provided in the form of a dynamic link library and a daemon program, respectively. In addition, the startup script must be modified to start the Wi-Fi service.Application layer, including most of the system services and all of the user interface, is responsible for controlling the state transitions of Wi-Fi module and interaction with the user. The power management, IP settings and other functions will be improved to further enhance the user experience.