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Hi,
did you get a warning like this : "object "rx_bar_hit" assigned a value but never read" ?
That means the signal "rx_bar_hit" is not used in your design and it looks like that it
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Yes. I'm not use this wire yet. But I'm expected that wire will be used by Signal Tap.
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is removed regardless of your "keep" assignment. I assume "keep" will only work in order
to prevent the signal to be removed by the synthesis engine.
BTW: "noprune" works only for reg ! in case they have no fan out.
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So, there are no way to make wire only for Signal Tap?