post P&R simulation problems

[quiet83]

I have two questions about post P&R simulation with SDF annotation.

1. I saw a warning like "Out of 28058 SDF statements, 28058 had null values." Do it mean that the SDF annotation have some problems?


2. When I do the post P&R simulation, if I set the default time scale less than 1 ns, there are some errors like $setup(xxxps, xxxps, xxxps) or $hold(xxxps, xxxps, xxxps), but it will dispear if I change the default time scale to ns.
Does anybody know what's the problem?

Thanks.

 

[mail4idle2]

1. Please upload log to answer your 1st question
2. You simulation timescale and sdf time scale might be mismatched. Please check

 

[quiet83]

1.
"# Loading timing data from /xx/xx/xx/top.sdf
# ** Warning: (vsim-SDF-3924) /xx/xx/xx/top.sdf: Out of 280583 SDF statements, 280583 had null values.
# ** Note: (vsim-3587) SDF Backannotation Successfully Completed.
"

Above is the only log content related to the sdf file. What does it mean by "had null values"? And in what kind of cases it will happen?


2. What do you mean "Your simulation timescale"? Is it the time resolution that I set for the modelsim when I do the simulation?
As I said in the first post, it only works when I set the default of the time resolution to ns.
I have also checked the time scale in the sdf file. In the source code of the core library, the time scale is 10ps / 1ps, and in the generated sdf file for the design, the time scale is 1.0 ns.

Thank you very much.