Video Driver is a software layer between OS Kernel and the video device. It abstracts the detail of video device, and provides the interface which OS Kernel needs. By means of OS, it manages devices to display images. The main goal of this project is to study the mechanism of Video Driver, and implements he Video Driver in Embedded Linux based on Intel XScale platform. Firstly This paper explains the foundation, principle and development of Video Driver, and it researches Video Driver in current ARM Linux2.4.19. It points out the advantage of Video driver which used the dual-level design, and It also explains the disadvantage which the Framebuffer console method brings, that you cannot compile the Video Driver without compile the console code. This causes memory to be used unefficiently, especially for Embedded System for example. Based on this analysis ,the new Video Driver for PXA255 is proposed in view of the features of PXA255: Referring to the original realization, redesigns new Video Driver. The new characteristic is removing the display console and adding the dynamic-modifying function of the palette. The shortage of original interrupt processing is also be revised. It can be easily ported to the XScale serial processor. This driver has already been used, and can successfully implement the display function. This indicates that the Video Driver realization method is correct after removing the display console. There are still something should be done to improve the dynamic-modifying function of the palette. Finally, this paper analyzes the shortage of this design, and proposed the tentative plans to the improvement and development of Video Driver. |