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Hi there,
warning: Can't achieve timing requirement Minimum Pulse Width Requirement (Low) along 3 path(s). See Report window for details.
critical warning: Timing requirements for slow timing model timing analysis were not met. See Report window for details.
Thank you
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Did you set frequency requirement for ur design? This warning seems that the design cannot fulfill your timing requirement.
However I agree with Bango's opinion about the clock n enable signal, or perhaps you just replace your "clock" input by "enable", it sounds more suitable.