【作者】 潘国振；

【导师】 严晓浪；

【作者基本信息】 浙江大学 ， 电路与系统， 2004， 硕士

【摘要】 集成电路技术的迅猛发展大大推动了SoC(片上系统)和计算机系统的前进，数据传输作为其中必不可少的一块内容也正经历着重大的变革。 为了统一数据传输的接口，业界制定了一系列标准协议。这些标准协议也正随着系统性能的提高而不断发展。文中将对这方面的内容做一定的介绍。 在系统的不同层次，数据传输的情况也是各不相同的。最直接的体现就是这些标准协议所规定的数据传输行为的不同。在本文中将对这些情况做一定的阐述与研究。 光谈论标准协议是不够的，因为它们还只是存在于纸上的定义和规范。真正的标准协议应该是体现在实际电路当中。与纯粹的逻辑电路设计不同，数据传输控制电路不仅肩负着数据传输控制的任务、使其符合标准协议的规定，而且它还维系着系统内部电路与外部总线的接口界面、使内外两部分电路能够很好地协同工作。 不同层次的数据传输，其内部电路与外部总线的时钟域匹配情况不同。有属于两个同步的时钟域，有的属于两个异步的时钟域，这会给电路的实现带来很大的区别，而在标准协议中是看不到这一层关系的。 随着数据传输总线时钟频率的提高，传统的并行总线已越来越显得力不从心了，于是出现了以串行传输为手段的最新技术。串行数据传输的时钟频率不受数字信号skew的影响，可以被极大幅度地提升。但由此也会产生一系列的问题，诸如高频电路的设计、时钟误差的补偿等等。这些也都将在本文中得到论述。 由于数据传输标准协议包含了实际情况中各种各样的异常处理情况，如何验证数据传输控制电路，使其达到极高的测试覆盖率也是比较值得研究和探讨的。更多还原

【Abstract】 It is the fast development of IC that forces the advancing of SoC and computer system,and as a necessary department of which, the data transfer is undergoing a bigevolution.In order to unify the interface of data transfer, the industry made a series of standardprotocols. These protocols are also being developed as the improvement of thesystem’s performance.The cases of data transfer are different at the different level in the system. It isreflected in the different standard protocols in which the behavior of data transfer isdifferent.It is not enough that we only talk about standard protocols, because they are onlydefinitions and rules on the paper. The real standard protocols must be reflected in thereal circuit. Being different from the pure logic circuit design, the data transfer controlcircuit is not only responsible for control the data transfer and make it follow thestandard protocol, but also responsible for connect the internal circuit with theexternal bus interface and make them work together properly.There are some differences on the matching between the internal circuit clock and theexternal circuit clock at the different data transfer level. Some belong to twosynchronous clock domains’ matching, while some belong to two asynchronous clockdomains’ matching. This will bring huge differences on the circuit implementation,but it can’t be seen on the standard protocol level.As the improvement of the data transfer’s clock frequency, the conventional parallelbus are becoming more and more uncompetitive. So the new technology which is baseon serial transfer occurs. The clock frequency of serial data transfer is not infected bythe data signal skew, so it can be improved dramatically. But this can bring a series ofproblems, such as high frequency circuit design, compensation of clock mismatch.Because the data transfer standard protocol includes all kinds of exception handling inthe real runtime, it is worthy to researching and discussing how to verify data transfercontrol circuit to achieve highest test coverage.更多还原