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Altera_Forum
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18 years ago

Megawizard FIFO problem: Write and read request filling FIFO!

Hi, Well this has to be the most bizarre problem I've ever encountered. I've found that the read request signal to the fifo occasionally results in the fifo used counter to be incremented and t...
Altera_Forum's avatar
Altera_Forum
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18 years ago

The vectors look like that when you get a FIFO to over / underflow. If that is the case you could see the full or empty pulse shortly before the capture window. Equality comparators are cheaper than LT/GT's, so once you overflow it tends to stay that way.

It is downright difficult to provoke a metastability failure at 133, so it's unlikely to be synchronization related.