Intel® Quartus® Prime Pro Edition User Guide: Timing Analyzer

ID 683243
Date 10/04/2021
Public

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Document Table of Contents

1.1.5.2. Multicycle Clock Setup

The setup relationship is defined as the number of clock periods between the latch edge and the launch edge. By default, the Timing Analyzer performs a single-cycle path analysis, which results in the setup relationship being equal to one clock period (latch edge – launch edge). Applying a multicycle setup assignment, adjusts the setup relationship by the multicycle setup value. The adjustment value may be negative.

An end multicycle setup assignment modifies the latch edge of the destination clock by moving the latch edge the specified number of clock periods to the right of the determined default latch edge. The following figure shows various values of the end multicycle setup (EMS) assignment and the resulting latch edge.

Figure 27. End Multicycle Setup Values

A start multicycle setup assignment modifies the launch edge of the source clock by moving the launch edge the specified number of clock periods to the left of the determined default launch edge. A start multicycle setup (SMS) assignment with various values can result in a specific launch edge.

Figure 28. Start Multicycle Setup Values
Figure 29. Start Multicycle Setup Values Reported by the Timing AnalyzerThe following shows the negative setup relationship reported by the Timing Analyzer.