PCI总线以其优越性得到了越来越多的应用,在总线扩展方面,相对于传统的共享式总线开关式总线可以动态分配带宽,很大程度上提高了系统的性能。该文提出了一种方案,使用交叉开关进行PCI总线的空分连接,以实现PCI总线的扩展,并介绍了PCI总线和交叉开关之间接口PXP的设计。 PCI bus has been more and more widely used because of its superiority. Compared with the traditional shared bus switch bus, the bandwidth can be dynamically allocated in terms of bus expansion, greatly improving the performance of the system. In this paper, a scheme is proposed, which uses the crossbar switch to connect the space division of the PCI bus to realize the expansion of the PCI bus. The design of the interface PXP between the PCI bus and the crossbar switch is also introduced.