And more than 70 % hardware are tested during microcode self - test since the execution of micro program can cover other data paths . boundary scan is designed according to ieee1149 . 1 , and some other instructions such as degug , runbist are provided to support internal fault testing , online debugging and built - in self - test besides the several necessary insructions . internal scan is implemented by partial scan , through this the boundary of logic component and user - cared system registers can be selected to be scanned Bist用于测试cpu的微码rom ,其它ram则利用微码rom中的微程序进行测试,而微程序的运行则可以顺带覆盖其它数据通路,从而使高达70 %的硬件得到测试;边界扫描按ieee1149 . 1标准设计,除必备的几条边界扫描指令外,还提供了debug 、 runbist等指令以支持内部故障测试、在线调试及内建自测试;内部扫描采用部分扫描策略,选择逻辑部件的边界及用户关心的系统寄存器进行扫描,从而实现了硬件逻辑划分,方便了后续的测试码产生和故障模拟,并为在线调试打下了基础。
Finally the design of rs decoder in this chip is described as an example of the hardware / software co - design based on asip , the construction and application of asip is also analyzed . the fourth chapter introduces the design flow using eda tools based on standard cell , then it presents the dft of this chip in detail which uses following techniques : full scan , bist and boundary scan to improve the fault coverage 第四章,在对本芯片的基于标准单元eda设计流程进行了简要说明基础上,对本芯片采用的可测试性设计进行了详细的分析和说明,本芯片中有机结合了多种可测试性设计技术:基于全扫描的方式、 bist测试技术、边界扫描技术,保证了很高的测试故障覆盖率。
Otherwise , as a memory component , large - scale register file holds a large number of data , so it requires stronger stability and validity . for memory components , using bist method to make a fault checking is a relatively good choice . but the bist of the multi - port register file is still in early phase of development 另外作为存储部件,规模大的寄存器文件现场保存量大,需要有很强的稳定性和正确性,而内建自测试是存储部件进行故障检测的较佳选择;但是多端口寄存器文件的测试却处在初始发展阶段,故障模型和测试算法都有待于进一步完善。
From the view point of the foundation of dft ( which includes the testable measure of gate - level circuits , the testable and controllable measure of functional - level , the flow and methodology of dft and so on ) , the author introduce some common testing technology such as scan and bist in modern times . especially the boundary scan technology has been widely adopted in the dft of vlsi . with the special controller , the testing vector could be scanned to the corresponding ports of inner cores from the testing input ports , and the response could also be shifted to the testing output ports 本文从可测性设计的基础理论出发(包括门级电路的可测性测度、功能级上的可测性和可控性、可测性设计的流程和方法等) ,介绍了现代常用的可测性技术,比如:扫描技术、内嵌自测试技术等,特别是边缘扫描技术已经广泛地应用到vlsi的可测性设计之中,它通过特定的控制器,从相应的测试输入端口将测试向量扫描至芯核所对应的管脚,再将结果从相应的测试输出端口扫出。