Hello, every one.
I find my ncsim can only simualte the sdf file in precision of 10ps (round to 10ps)
For exampe,This is a simple BUF sdf information:
Code Verilog - [expand] |
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| (CELL
(CELLTYPE "BUFCLKHD30X")
(INSTANCE U10)
(DELAY
(ABSOLUTE
(IOPATH A Z (0.263:0.266:0.266) (0.257:0.259:0.259))
)
)
) |
But when I observe the timing sequence in simvision window. I found the simulator will round it to 270ps for example in when Z transfering from 0 to 1.
In my sdf file the Timescale (unit) is 1 ns. And in my testbench is 1ns/1ps. And according the tools documentation from cadence, the default timing precision of sdf elaberating/compiling is 1fs. I think that means we do not need to set any precision relating compiler option (like sdf_precision 1ps)in ma case. (BTW, I have tried such complier option, but still not wokr for my precision).
Anyone can teach me how can I watch/oberseve a delay of 266ps from my simulation window! Mnay thanks.!
My ncsim version is IES 2012, I thnik it was "latest" enough.
Many thanks.