UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 1426

Orcad - Orcad VST: All outputs are undefined

Description

Keywords: VST, Orcad, undefined, simulation

Urgency: Standard

General Description:
A file such as "<design>.vst" loads without errors, but all outputs remain undefined.
Trace and stimulus are defined correctly. Even if the global reset has been asserted,
the flip-flop outputs are still undefined.

解决方案

The simulator option Prefix 'G' needs to be used.

With VST 386+ versions 1.1 and older, the line:

PREFIX = 'G'

should be added to the VST configuration file (vst.cfg).

This can be done in three ways:
1. Running XDraft with version 1.1 should automatically add this line.
2. Edit the vst.cfg file and add the line: PREFIX = 'G'
3. From Orcad ESP, select Digital Simulation Tools -> Execute -> Simulate ->
Configure Digital Simulation

Scroll down to the section that says "Prefix Options" and type ""G in one of
the Prefix Definitions boxes.

The format of VST 386+ version 1.2 was changed so that all prefixes could
be used except those that were specifically ignored.

Edit the vst.cfg file and look for the line:
IPREFIX = 'G'

If you find this line, delete the G and save the file;

or

From Orcad ESP:
Digital Simulation Tools -> Execute -> Simulate -> Configure Digital Simulation

Scroll down to the last section that says "Prefixes IGNORED by VST"

If G is one of the Prefix Definitions, delete it.
AR# 1426
创建日期 08/31/2007
Last Updated 10/01/2008
状态 Archive
Type 综合文章