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Altera_Forum
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11 years ago

strange behavior of DCFIFO, how to meet the "Functional Timing Requirements"

Hi, My DCFIFO on Cyclone V is broken. Data is lost. depends on FIFO type, MLAB or M10k, data corruption is severer as FIFO larger. I wrote to DCFIFO like this: if(~fifo_fu...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

What exactly do you find strange?

Remember that a DC fifo is dual clock, so it takes a few clocks to pass the address pointers accross the domain, so the empty flag will not de-assert for a few clocks after a write operation. Similarly, the full flag will not de-assert until a few clocks after a read operation.