Design And Realization Of Embedded System Developing Platform System Function Layer

An embedded system developing platform which supports embedded system resource reusage, reduces embedded system developing period and improves developing efficiency is an effective utility for embedded product developing. However, along with the rapid development of embedded system and improvement of industrialization, the new situation has put forward stricter requirement for embedded system and it is mainly embodied in the expansibility of embedded system, organization and storage way of program and data as well as the management ability on peripheral device and so on. So we considered all the above factors when designing the embedded system developing platform, and have built a developing platform with strong expansibility, effective and reasonable data organization, rich function of device management to make the developing platform more suitable for the embedded system designing.The mainly task of this thesis is the design and realization of the system layer of embedded system developing platform based on layer model. System layer is an important component in layer model of embedded system developing platform. Its mainly function is providing management methods for files and device in the embedded system application, and providing system service API. An consummate design on system layer of embedded system developing platform is put forward based on the detailed research of available system expansibility techniques, composing and configuration of file system and device management way.The system layer is divided into two mainly function modules (file management and device management) and part assistant modules (such as network protocol Stack management and the kernel layer service API). Dynamic loading or removing mechanism is realized with the kernel expanding technique during the design of file and device management, which make the ability of expansibility and maintenance of embedded system stronger. The file management module sustains the compatibility to many kinds of file systems by building the File System Abstract Layer (FSAL). The FSAL supplies the universal operation management interface of file and it's realization of interface is depended on the material file system that is connected to FSAL. In the device management, the device is taken as a particular file and operated with the way of file management. It sustains loading or removing of any given device. This design can well satisfy the expansibility requirement of embedded system to special application and apply the effective solving method to data resource storage, organization and the control management of peripheral device.