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AR# 3932

4.2i Foundation Simulator - What do the "Functional" and "Timing" modes do?

Description

Keywords: Foundation, Simulation, Timing, Functional, selection

Urgency: Standard

General Description:
A pull-down menu in the Foundation Simulator allows me to select Functional, Timing, Glitch and Unit.

What do the "Functional" and "Timing" pull-down options do?

Can I perform a timing simulation directly from the start of the simulator using the "Funct Sim" button in Foundation Project Manager if I select the "Timing" option?

Solution

1

The "Functional" option provides a simulation with zero delays. This allows the user to verify the logical function of the design.

The "Timing" option provides a simulation with defined delays. This allows the user to verify that the design operates properly with real-world delays.

2

An accurate timing simulation cannot be performed using only the above steps.

To perform a timing simulation, the design must be run through the Implementation tools (Implement button), with the "Produce Timing Simulation Data" box checked (an option in the Design Manager -> Implement -> Options).

Once the implementation is finished, select the "Sim Timing" button in Project Manager. This will load the back-annotated netlist of your design, which contains accurate delays.

If you select the "Functional" option while performing a timing simulation (Sim Timing button), this will place you back into zero-delay simulation.

For more information, please consult the available documentation (Dynatext, Foundation Online Help, Quick Start Guide.)

NOTE: If the "Timing Simulation" option is selected from within a Functional simulation session (Sim Funct button), results that differ from the Functional simulation will be reported. However, the delays used for this timing simulation are default values defined by Foundation and are not related to the actual delays that the design will experience. This flow is not recommended.

For information on the "Glitch" and "Unit" options, please consult Foundation Online Help.
AR# 3932
Date Created 05/19/1998
Last Updated 08/12/2003
Status Archive
Type General Article