5X00070G01  现场总线接口模块

总线接口：显示卡要插在主板上才能与主板互相交换数据。与主板连接的接口主要ISA、EISA、VESA、PCI、AGP等几种。ISA和EISA总线带宽窄、速度慢，VESA总线扩展能力差，这三种总线已经被市场淘汰。现在常见的是PCI和AGP接口。PCI接口是一种总线接口，以1/2或1/3的系统总线频率工作（通常为33MHz），如果要在处理图像数据的同时处理其它数据，那么流经PCI总线的全部数据就必须分别地进行处理，这样势必存在数据滞留现象，在数据量大时，PCI总线就显得很紧张。AGP接口是为了解决这个问题而设计的，它是一种专用的显示接口（就是说，可以在主板的PCI插槽中插上声卡、显示卡、视频捕捉卡等板卡，却不能在主板的AGP插槽中插上除了AGP显示卡以外的任何板卡），具有独占总线的特点，只有图像数据才能通过AGP端口。另外AGP使用了更高的总线频率（66MHz），这样极大地提高了数据传输率。 

Bus interface: The display card needs to be inserted on the motherboard to exchange data with the motherboard. The interfaces connected to the motherboard mainly include ISA, EISA, VESA, PCI, AGP, etc. ISA and EISA buses have narrow bandwidth, slow speed, and poor scalability, making them obsolete in the market. The common interfaces nowadays are PCI and AGP. PCI interface is a bus interface that operates at a frequency of 1/2 or 1/3 of the system bus (usually 33MHz). If image data is to be processed while other data is being processed, all data flowing through the PCI bus must be processed separately, which inevitably leads to data retention. When the data volume is large, the PCI bus becomes very tight. The AGP interface is designed to solve this problem. It is a dedicated display interface (that is, sound cards, display cards, video capture cards, etc. can be inserted into the PCI slot of the motherboard, but no board other than the AGP display card can be inserted into the AGP slot of the motherboard), with the characteristic of exclusive bus. Only image data can pass through the AGP port. In addition, AGP uses a higher bus frequency (66MHz), which greatly improves the data transmission rate.