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Orcad VST all outputs are undefined


Record #1426

Problem Title:
Orcad VST all outputs are undefined


Problem Description:
Keywords:  vst, orcad, undefined, simulation

Urgency:  Standard

Problem Description:
<design>.vst loads without errors but all outputs remain undefined. Trace and st
imulus are defined correctly.
Even if the global reset has been asserted the FF outputs are still undefined.


Solution 1:

Simulator Options Prefix 'G' need 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 the letter G in one of the Prefix Definitions boxes.


With VST 386+ version 1.2 the format was changed so that all
prefixes could be used except the ones that were specificly
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 then delete it.



End of Record #1426