Can i make relative delays in timequest (9.1)

Hi again

We have allready hand placed the 4 registers close to each other in the second row/colomn from the pin (for some reason the second is better than the first), but we see that the routing variate from fit to fit, the skew might get too big when we have a high fill degree.

We have never locked down routing and do not know how to do that?

(Never got around to learn to use the chip planner beside looking at placement, it seems to be quit a job to learn the chip planner GUI.)

Our general experience is that if you lock down many thinks you can not fit after a small change and it becomes too complex to find out why.

My first fit after adding a skew of 200pS improved result from around 450ps to max 372pS. I will try with 300ps as 200pS might be too tight.

Any think else we should set beside optimize multi-corner timing to make it optimize?