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AR# 612

9.2i Timing Analyzer - Timing report displays an increase of items analyzed for my constraints

Description

When I review the items analyzed for my constraints, I notice the number of paths increased compared to 8.x analysis. What caused this?

Solution

A bug was found in the timing engine of the 8.x software that was fixed in the 9.x release. This bug caused some paths in the carry chain and input logic to be removed from analysis. This bug affected only Spartan-3 and Spartan-3e devices.

We recommend rerunning timing analysis with 9.x or 10.1 timing analyzer. If you are unable to migrate to 9.x or 10.1, you can add the following in your PCF:

For s3:

ENABLE = Tcinxb;

ENABLE = Tdiffin;

ENABLE = Tioftiq;

For s3e:

ENABLE = Tcinxb;

AR# 612
Date Created 04/24/2008
Last Updated 01/18/2010
Status Archive
Type General Article