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Altera_Forum
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13 years ago

A question about rd_usedw and wr_usedw for a DCFIFO

Hello all, Recently I used a dcfifo mega core to buffer datas, I found there're 2 signals for usedwidth : rd_usedw and wr_usedw I don't understand the difference between these two signa...
Altera_Forum's avatar
Altera_Forum
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13 years ago

Are you looking at the usedwd value in the read clock domain or write clock domain? You want to choose the right one so that you can safely capture it. (If you took wr_usedw and analyzed it in the read domain, you will read the wrong data because the clocks aren't synchronous).