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Altera_Forum
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8 years ago

FIFO Works fine on EDAPlayground but not Quartus

All, The following code works fine and as expected on EDAPlayground, but Quartus has an issue with it. I get the ERROR 10028 Can't resolve multiple constant drivers for nets w_addr and r_addr. ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
8 years ago

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I guess I don't understand. If I reset them in each posedge process, then they will always be zero, and the array will not increment. I do set them to zero in my nrst section.

Keith

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Inside each process the assignments are treated as sequential. But each process runs parallel to any other process.

So by having separate processes on your same signal you are driving it twice in parallel. This is mutiple driver case and HDL standard is against it and I assume tools should respect it or not.