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M1 : How to change speed grades (faster or slower) of your placed and routed design? How to recreate simulation and static timing models?


Record #2630

Problem Title:
M1 : How to change speed grades (faster or slower) of your placed and
routed design?  How to recreate simulation and static timing models?



Problem Description:
Keywords: Speed grade, simulation,

Urgency: Standard

models for a different (faster or slower) speed grade of the same
placed and routed design (ie. 4005E-3 --> 4005E-2)?


Solution 1:


Timing Simulation Models
========================

In order to change speed grades and create a new simulation model.  The
post-placed and routed design file need to be loaded into Epic so that
the delays may be re-calculated for the design file and subsequant
simulation files.  The following steps assume that you have already
placed and routed the design as well as created a simulation model for a
previous speed grade of the same device :

From Design Manager:
-------------------

1.  Open Flow Engine (Tools --> Flow Engine) and back up the
    implementation steps so that the "Place&Route" step is completed
    but the Timing portion is not.  To back up the Flow Engine, either
    select (Flow --> Step back) or depress the backward arrow button
    until you are at the desired portion of implementation.  Close the
    Flow Engine.

2.  Load design in Epic by selecting (Tools --> Epic) Design Editor.

3.  Once the Epic Design Editor has loaded, select
    (Misc --> Post Main Attrs...) From the Main Attributes Window,
    Select the desired speed grade from the Speed selection box and
    hit OK.

4.  Save the design in Epic by selecting (File --> Save).  Exit Epic.

5.  Re-create the simulation model with Design Manager by opening the
    Flow Engine (Tools --> Flow Engine) and finishing implementation
    (Flow --> Run).

6.  The up-dated simultion files should be created for the new speed
    grade.

7.  Re-run simulation.

From Command-line :
-----------------

1.  Load placed and routed .ncd design file in Epic:

    epic <routed design>.ncd

2.  Once the Epic Design Editor has loaded, select
    (Misc --> Post Main Attrs...) From the Main Attributes Window,
    Select the desired speed grade from the Speed selection box and
    hit OK.

3.  Save the design in Epic by selecting (File --> Save).  Exit Epic.

4.  Re-run ngdanno on the newly written .ncd file from Epic:

    ngdanno [-o <ngafile[.nga]>] [-p <pcffile[.pcf]>] <ncdfile[.ncd]>
    [<ngmfile[.ngm]>]

5.  Re-run the program to re-create the simulation model for your
    simulator (ie. ngd2edif, ngd2xnf, ngd2ver, ngd2vhdl, etc.).
    Use the same commandline as previously to recreate a similar
    simulation file.  Note: if a simulation file already exists, you
    must use the -w switch to allow the software to overwrite the
    previous design file.

6.  Re-run simulation.



Solution 2:


Static Delays (Creation of Simulation Models is Resolution 2)
=============

If you wish to see the overall design performance or wish to find
the static timing delays of paths with a different speed grade,
you can do so from either the graphical static timing tool,
"Timing Analyzer" or from command-line static timing tool,
"Trace" (trce).

Using Timing Analyzer:
---------------------

1.  Load in design to be examined
2.  Select from the menu: (Options --> Speed Grade)
    <Select desired speed grade> --> OK
3.  Perform design Analysis

Using Trace:  Specify the new speed grade with the -s switch:
-----------

trce -s <speed> [other options] <design[.ncd]> [<constraint[.pcf]>]



End of Record #2630