Answers Database

M1.4 CPLD: The OFFSET timing constraint does not force the fitter to useglobal clocks


Record #2913

Product Family:  Software

Product Line:  CPLD Implementation

Problem Title:
M1.4 CPLD: The OFFSET timing constraint does not force the fitter to
useglobal clocks



Problem Description:
Keywords: OFFSET, BUFG, global clock

Urgency: Standard

General Description:

If you use an OFFSET timespec on a net, the fitter does not force that net
to be a global clock net automatically.


Solution 1:

A BUFG=CLK property must be manually provided on the clock pad of the net that
has the OFFSET timespec associated with it.



End of Record #2913