Encounter issue with Core and Hard macros

[p_shinde]

Encounter problem

hi,

after importing a design into encounter i get
topmodule
Core
and Hard macros.


so later in the tutorial of encounter its mentioned that we have to move the submodules into core, so what do we have to end up with , by placing all submodules into the core area?????????

and where r hard macros going then ? first of all what are hard macros?

reply soon.
Prasad

 

[Manoochehr]

Re: Encounter problem

Some terminology of encounter:
1) In Encounter, design area (or die area ) is divided into two section:
The core area
IO pads area.

So everything except from pads will b e placed in core are.

2) The design elemets can be of two type:
Std cells: You know?!
Hard macro: These are module that has fixed layout, e.g. Memory blocks, analog blocks, ... . Hard means that the block lets no flexibility for encounter to change the block.

But other modules/ macros ( except for hard macros) are soft modules since they are collection of std. cells and are for representng the hirerachy of design.

3)The first step( after design import) is floorplaning. In this step will place the Hard macros and also will floor-plan the remaining modules.

This will endup with a floorplaned design, ready for power plannig and placement.

 

[fpgafresh]

Why are Macros placed in the corner of the site? Why not in the middle?

 

[ebuddy]

Macros are usually designed in the way so that all their IO pins are on one side (sometime 2 sides) of the rectangle. So by placing macros on the corner, all their pins are exposed to the core area, while the core area is still kept as a big piece of continuous space for std cell placement and routing.