摘要： 能否设计一个可屏蔽不同嵌入式RTOS 差异的平台抽象层，对于软件产品能否迅速向新的RTOS 平台移植、能否迅速提供多平台的支持，以较低成本快速应对技术的改进和市场的变化等方面都非常关键。平台抽象层设计的原理及设计过程中需要考虑的因素是讨论的主题。

关键词: 平台抽象层；实时操作系统；嵌入式软件

Abstract: If a PAL can be created that can mask the difference of embedded RTOS, some important features can be got for software product,porting easily to new embedded RTOS, providing rapidly for the support of multi-platform and responding rapidly to the technical improvement and market change with low cost. The design principles of PAL and factors that must be considered are covered in this document

Key words: Platform abstraction layer; Real-time operating system (RTOS); Embedded software