AR# 8542

4.2i Foundation Logic Simulator - Bidirectional signals may not simulate correctly if they are not locate in the top level of a design

描述

Keywords: Foundation, simulator, bidirectional, macro

Urgency: Standard

General Description:
When a bidirectional signal is placed inside a macro (not on the top level) in a design, the Foundation simulator may not simulate the signal correctly in timing simulation. It may appear in the simulator that the signal is an output rather than a bidirectional signal.

解决方案

1

This is due to the way the back-annotation program interprets bidirectional signals that are not on the top level of the design hierarchy.

A possible way to work-around the problem is to disable the "Correlate Netlist to Input Design" option in the Timing Simulation stage of implementation. To disable this option:

1. From the Project Manager, select Implementation -> Options
2. Click the Edit Options button next to Simulation
3. On the General tab, ensure that "Correlate Netlist to Input Design" is not selected

2

It is recommended that all ports of a design be placed on the top level of the design hierarchy. This practice will ensure that the design will correctly simulate in the Foundation simulator.
AR# 8542
日期 06/13/2002
状态 Archive
Type 综合文章