Clock Register Groups in OFFSET

Clock register time groups allows the user to define a specific set of registers to which an OFFSET constraint applies based on a clock edge. Consider the following example.

CLK

DATA

You can define time groups for the registers A,B, and C, even though these registers have the same data and clock source. TIMEGRP AB = RISING FFS; TIMEGRP C = FALLING FFS; This allows the user to perform two different timing analysis for the registers.

NET CLK PERIOD = 45nS;

OFFSET = IN 10 BEFORE CLK TIMEGRP AB;

OFFSET = IN 20 BEFORE CLK TIMEGRP C;

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Clock Register Groups in OFFSET

Clock register time groups allows the user to define a specific set of registers to which an OFFSET constraint applies based on a clock edge. Consider the following example.