余亚东, 朱荣, 彭峰, 喻占武. BSP在TriMedia多媒体应用系统中与应用程序互通的一种简单实现[J]. 武汉大学学报 ( 信息科学版), 2002, 27(1): 48-51.
引用本文: 余亚东, 朱荣, 彭峰, 喻占武. BSP在TriMedia多媒体应用系统中与应用程序互通的一种简单实现[J]. 武汉大学学报 ( 信息科学版), 2002, 27(1): 48-51.
YU Yadong, ZHU Rong, PENG Feng, YU Zhanwu. A Simple Method of Realizing Intercommunication between BSP Based on Embedded System and Application Program[J]. Geomatics and Information Science of Wuhan University, 2002, 27(1): 48-51.
Citation: YU Yadong, ZHU Rong, PENG Feng, YU Zhanwu. A Simple Method of Realizing Intercommunication between BSP Based on Embedded System and Application Program[J]. Geomatics and Information Science of Wuhan University, 2002, 27(1): 48-51.

BSP在TriMedia多媒体应用系统中与应用程序互通的一种简单实现

A Simple Method of Realizing Intercommunication between BSP Based on Embedded System and Application Program

  • 摘要: 在分析嵌入式操作系统板级支持包开发设计方法的基础上,提出在应用软件与板级支持包(BSP)之间加一层库函数,同时使用链表来组织管理板级支持包函数的方法,较好地解决了应用程序与板级支持包函数间的通信问题,并减少了板级支持包函数的维护复杂度,为嵌入式系统板级支持包的实现提供了一个有价值的思路。

     

    Abstract: The software layer that describes the interface between the software on chip and any peripherals on the board is known as the board support package,or BSP.BSP allows to change the boards design without affecting the software that has already been developed.This paper tries to describe a method of communication between application program and BSP and organizing of functions in BSP which work with Philips TM1x00 CPU and pSOSystem embedded operating system,or pSOS.TM1x00 is a media processor for high-performance multimedia applications that deal with high-quality video and audio.pSOS is a modular,high-performance real-time operating system designed specifically for embedded microprocessors.A basic BSP consists of many files about every peripheral.One of those has a few functions which initialize corresponding peripheral and finish the function that application program needs.This paper brings forward a method to connect the application program and functions in the BSP.The method adds a series of libraries which make users application program need not consider the hardware.It can only call the library to finish the operation about hardware.Accordingly the library calls the functions in BSP to control hardware or get information about hardware and return to application.In addition,this paper uses a chain table to manage the functions in BSP.These functions'name are defined as functions'pointer.These pointer are put into a structure.Functions'pointer variables about the same peripheral are all put into a structure.The address of the structure is added to chain table.So all peripheral structure form a chain table.Library searches the chain table to obtain the address of structure and call the corresponding function.Of course,the chain table should be built during the system startup and before the application program of user is executed.Then when application program is running,it can call the library to use chain table in any time.This article provides a thought of realizing the BSP communicating with application program.The application program of user is very clear when the librares are used to be an interface between it and BSP.Use of the chain table makes it easy to manage the BSP.When hardware needs to be upgraded,the chain table makes the change for BSP appear to be in proper order.So these two methods have some value in realizing it.

     

/

返回文章
返回