Article ID: 000084413 Content Type: Troubleshooting Last Reviewed: 11/18/2011

Incorrect Clock Uncertainty in UniPHY External Memory Interfaces

Environment

    Quartus® II Subscription Edition
BUILT IN - ARTICLE INTRO SECOND COMPONENT

Critical Issue

Description

A clock uncertainty related to the read FIFO clocked by DQS can result in inaccurate setup and hold slack values.

Resolution

The workaround for this issue is to manually edit the PHY .sdc file located in the <variation_name>/constraints/ directory, and add the following two lines to the Multicycle Constraints section of the file:

set_max_delay -from *ddio_in_inst_regout* -0.05 set_min_delay -from *ddio_in_inst_regout* [expr - 0.05].

Related Products

This article applies to 1 products

Intel® Programmable Devices

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