Stats

  • Locked Locked
  • Replies 1
  • Subscribers 91
  • Views 13751
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

ILM in encounter 8.1

DavidMZ

Hi there,

as said in the title I'm trying to use ILM (Interface Logic Model) in encounter 8.1.

In that aim I made a simple design consisting of one single instance of a block, which block is using ILM.

My problem is, when I try to "placeDesign" as stated in the example top-level implementation flow using ILMs chapter of the encounter manual, I see that the stdcells INSIDE the block are placed at their "best" locations, which means:

                      -different locations than what I had in the original block

                      -illegal locations (->stacked stdcells, stdcells in the block power ring)

 Of course I had to do a "flattenIlm" after the "placeDesign" command in order to see the stdcells.

 Is it a normal behavior?

 Thanks you for your answers,

David

 

Parents

  • A recent tentative of modifying the .def files inside the ILM directory didn't change a thing to my problem (I replaced all the "PLACED" statements by "FIXED" ones, since I figured out I had many "PLACED" instances in the .def, even though everything is clearly "fixed" in my original design...)

    Also, my few tentatives of performing an STA were also unsuccesful. I do have a .sdc file for the top, and I also wrote out .sdc files when generating the ILM module, but seeing the results of an STA I assume the ILM has no timing information. Taking into account this post: http://www.cadence.com/Community/forums/p/16435/968523.aspx#968523, I'm currently considering giving up using ILMs since they are too unreliable. This being said to warn future users (nevertheless, I would be very glad to be wrong!)

Reply

  • A recent tentative of modifying the .def files inside the ILM directory didn't change a thing to my problem (I replaced all the "PLACED" statements by "FIXED" ones, since I figured out I had many "PLACED" instances in the .def, even though everything is clearly "fixed" in my original design...)

    Also, my few tentatives of performing an STA were also unsuccesful. I do have a .sdc file for the top, and I also wrote out .sdc files when generating the ILM module, but seeing the results of an STA I assume the ILM has no timing information. Taking into account this post: http://www.cadence.com/Community/forums/p/16435/968523.aspx#968523, I'm currently considering giving up using ILMs since they are too unreliable. This being said to warn future users (nevertheless, I would be very glad to be wrong!)

Children
No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.