Saving PAR Constraints

Hi

I am doing an iterative design flow and iam using Xilinx 9.2i ISE
I am a newbie in Floorplan and PAR.

I wanted to set some constraints in Floorplanner.
Every time i change a constraint in floorplanner, for example placing
a LUT,
and run PAR the whole placements of other blocks gets changed.

Is it possible to save the constraints generated after PAR..?
i want to first make other blocks static and place my block at
different locations and evaluate timing..


Please help me



hoping your reply

On Tue, 26 Aug 2008 23:39:53 -0700 (PDT), knight
wrote:

>I wanted to set some constraints in Floorplanner.
>Every time i change a constraint in floorplanner, for example placing
>a LUT,
>and run PAR the whole placements of other blocks gets changed.
>
>Is it possible to save the constraints generated after PAR..?
>i want to first make other blocks static and place my block at
>different locations and evaluate timing..

I think you want to select "re-entrant flow" in the PAR properties menu
(there will be a command line option for this if you are not using
Project Navigator)
Read how to use re-entrant flow in the PAR manual.

- Brian

On Aug 27, 4:49*pm, Brian Drummond
wrote:
> On Tue, 26 Aug 2008 23:39:53 -0700 (PDT), knight
> wrote:
>
> >I wanted to set some constraints in Floorplanner.
> >Every time i change a constraint in floorplanner, for example placing
> >a LUT,
> >and run PAR the whole placements of other blocks gets changed.
>
> >Is it possible to save the constraints generated after PAR..?
> >i want to first make other blocks static and place my block at
> >different locations and evaluate timing..
>
> I think you want to select "re-entrant flow" in the PAR properties menu
> (there will be a command line option for this if you are not using
> Project Navigator)
> Read how to use re-entrant flow in the PAR manual.
>
> - Brian

Hi,
You can open the Place and Route design in the FloorPlanner.
Go to Floorplan Menu -> Replace All with placement . This will copy
the currently placed design into the Editable Floorplanner.
Now you can do the required changed in the LUT location in the
edittable window. Save this to the UCF file and use this as the UCF
file

Lux

> Hi,
> You can open the Place and Route design in the FloorPlanner.
> Go to Floorplan Menu -> Replace All with placement . This will copy
>
> Lux


Thank you that solved it...