Article ID: 000075137 Content Type: Troubleshooting Last Reviewed: 09/11/2012

Why don't my reported I/O times change when I rerun timing analysis with a different input clock frequency setting on my phase locked loop (PLL) with a phase shift?

Environment

BUILT IN - ARTICLE INTRO SECOND COMPONENT
Description For Stratix and Stratix GX devices, the project clock settings override the PLL settings. This problem with reported I/O times may occur if you change the input clock frequency setting for a PLL through the Settings dialog box, when the PLL is configured to provide a phase shift. The Quartus® II software will not recalculate the phase shift delay in this case when performing timing analysis. This problem could affect the I/O times reported during timing alanysis.

To avoid this problem, rerun the fitter before performing a timing analysis with the changed input clock frequency.

This problem is scheduled to be fixed in a future version of the Quartus II software.

Related Products

This article applies to 1 products

Stratix® FPGAs