Warning-[NTCDNC] Negative Timing Check Did Not Converge Negative timing check delays did not converge, trying to solve by setting minimum constraint to zero. 当2个以上的timing check使用同一个reference event(比如 posedge ck),且这些timing check检查的时间窗口没有重合时,EDA工具没办法处理这种情况,即...
(一)SDF3.0 Timing Checks主要分以下两种: VCS/NC-Verilog后仿真在timing violation时报出warning; Timing Sign-Off工具报出timing check violations; 以时序分析工具Sign-Off为主,后仿为辅,SDF3.0 Timing Checks具体的类型如下: Setup Timing Check Hold Timing Check SetupHold Timing Check 注意,示例中~reset必须为...
Period Timing Check 示例中,两个连续上升沿之间或两个连续下降沿之间的最小Cycle时间。 No Change Timing Check 示例中,addr提前write下降沿4.5个time unit, addr晚于write上升沿3.5个time unit。 (二)SDF3.0 Timing Environment Entries SDF3.0Timing Environment Entries分成Constraints与Timing Environment两个部分,首先...
Active-HDLloads SDF data when simulation is initialized (not when you start running the simulation with the run command). SDF error limitspecifies that all SDF errors should be reported to the Console window. If omitted, only the first 100 errors are printed and then the total number of erro...
1,仿真参数:去掉+nospecify +notimingcheck -add_dwq_delay 0.01ns 2,使用$sdf_annotate将延时加入网表 所谓的SDF文件就是:Standard delay file,它是把布局布线过程中器件延时和线延时的信息保留下来,据此就…
Timing Violation处理方式: 解复位后除了确认input端口激励和异步上报外,不允许有时序违例;否则检查 sdf反标模块及网表因素;异步相关的可以进行预处理: X态相关处理: 参考: https://segmentfault.com/a/1190000042956705 后仿真目的: 作为动态时序分析(STA是静态时序分析),更加关注异步路径、异步-同步转换、MultiCycle、...