Xilinx Multipass PPR

[Dan K]

I've recently started using MPPR to try and get better timing results. I
know there are a lot of "better" way to do it, but if I can MPPR over a
weekend and get the results I need - that's easy and good enough for me.

It seems to me that MPPR is critically flawed in that it only operated on
the results of one specific Map. If the Map seed isn't a very good one, all
MPPR results will be poor. Is there anyway to get MPPR to vary the Map seed
too? Or, better yet, is there a "multipass Map" that you could use to get a
really good Map before going to PPR?

Thanks

Dan

[Gabor]

Which version of ISE are you running? The map settings for earlier
versions needed to have "Timing-based Packing and placement"
turned off for a meaningful multipass run. For 10.1i I know
you can set the placement table entry when you enable the timing-
based placement for Map, but I don't know if you can run multi-
pass Map + place + route without writing a Tcl script.