若确保设计没有问题,可使用set_case_analysis或quasi_static命令加强对输入信号的约束。 setup_quasi_static 准静态寄存器是指设计中的输入信号、寄存器、线网在芯片工作开始时改变,但在接下来的工作中保持为0或1。 setup_quasi_static报告设计中spyglass推断出的准静态寄存器和约束脚本约束的静态寄存器。应仔细检查信号...
特殊情况下不会报违例:两个信号由同一个控制信号控制 如果spyglass报出违例,但通过检查发现设计没有问题,可使用 cdc_false_path , quasi_static, cdc_filter_conherency等命令约束。 AC_conv02规则报告信号经过同步器后聚合违例,且聚合后又通过寄存器:报告不同信号经过同步器后在同一个逻辑门处聚合问题 注意这里报...
⑨ cdc_reduce_pessimism:Set this parameter to an appropriate value to ignore clock domain crossings involving black box instances and clock domain crossings with destinations having unused, hanging, or blocked outputs. similar to cdc_false_path or quasi_static. 8. spyglass的每一步check都用gui界面d...
●虚拟时钟域: 如果一个虚拟时钟与一个块实例端口的主端口相关联,则SpyGlass将显示用户指定的虚拟时钟名。 ●Quasi_static 选择此选项以检查net在数据或控制路径中是否是准静态的,如下图所示: FIGURE 16. The quasi_static Debug Data Dialog 7.4 基于实例来过滤违例 在处理大型设计时,设计师会被分配特定的设计实例。
Quasi_static 选择此选项以检查net在数据或控制路径中是否是准静态的,如下图所示: FIGURE 16.The quasi_static Debug Data Dialog 7.4 基于实例来过滤违例 在处理大型设计时,设计师会被分配特定的设计实例。在这种情况下,设计师需要关注特定实例中报告的违规情况。为了帮助设计人员快速定位特定实例上的违规,SpyGlass ...
An example of such crossings may be configuration and other quasi-static registers which do not need synchronizers. The SpyGlass CDC solution provides a constraint, cdc_false_path, as the main CDC filtering capability. The cdc_false_path constraint allows you to specify the paths so that the ...
执行cdc_setup_check、cdc_verify等检查，过滤违反cdc_false_path的约束，设置quasi-static处理静态寄存器。七、减少运行时间 考虑降低LCM精度以缩短运行时间，需谨慎操作。八、错误与解决方案 面对Error和Fatal错误时，可参考具体的错误代码进行对应解决，如检查license、路径设置、忽略规则等。九、知识点 理解...
many verification challenges confronting system-on-chip (SoC) designers today, clock domain crossings (CDC) ranks near the top in difficulty. Today’s SoCs have dozens, sometimes even hundreds, of asynchronous clock domains, making it very difficult to verify using conventional simulation or static ...
It also detects the list of potential quasi-static signals allowing users to review the auto-generated list and use them as part of the setup. This correlation helps to produce CDC analysis with the lowest possible noise. VC SpyGlass CDC has integrated structural and functional CDC analysis. ...
Protocol Independent Analysis, recognition of widest variety of synchronizers and auto detection of quasi-static signals resulting in the lowest number of false violations Architecture for scalable CDC and RDC verification Simple setup by automatically extracting the clock, reset and clock domains informatio...