skill code to find instances and nodes

[Mark Summers]

my ultimate goal is to generate a skill routine that will extract timing
information from a spectre(most likely run through ocean) to allow for
digital timing verification on custom digital blocks. I want to get setup
and hold margin.

In order to accomplish this I need to find the clock and data inputs of all
flip-flops in the schematic. I need a function that will search through the
hierarchy for instances that are flip-flops and then return the nodes
connected to the data and clock inputs. These nodes that are returned need
to be correct with respect to the simulation schematic hierarchy. IE if a
flip-flop is two levels down the hierarchy, then the function should return
ILEVEL1/ILEVEL2/NODENAME

Any help in locating nodes in a simulation schematic attached to certain
instances would be very helpful.

Also if anyone knows of the location of skill scripts that already implement
digital timing verification that would be very helpful.

 

[DReynolds]

Mark, for each instance you can get the terminals (instTerms) and from
that you can tell if it is clock and data (assuming you know the names
of the terminals or the clk and data net names)

The place where the code gets very painful is if you allow busses and
iterated instances, then the net names for instance in the schmatic
are not exactly the same as in the sim (data<7> vs
data<7:0&gt

If you can avoid those issues, it is fairly straight forward


David