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AR# 37872

CPLD Timing - When applying PERIOD constraints and using KHz or MHz the constraint is not analyzed

Description


Applying the following constraint is not analyzed:
NET "64K_IN" TNM_NET = "64K_IN ";
TIMESPEC "TS_64K_IN" = PERIOD "64K_IN " 0.128 MHz HIGH 50 %;

Solution

It is not valid to apply a frequency for the constraint; it must be entered as ps, ns, us etc. So, the constraint should be as follows:

NET "64K_IN" TNM_NET = "64K_IN ";
TIMESPEC "TS_64K_IN" = PERIOD "64K_IN " 7.81 us HIGH 50 %;
AR# 37872
Date Created 09/10/2010
Last Updated 12/15/2012
Status Active
Type General Article
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