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Altera_Forum
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11 years ago

Q14 Web edition replace top level out port with buffer

Hi I've done a top layer entity with (of course) some out port. I also made a testbench in order to verify the design. The problem is that Quartus sometimes generate a post-fitting simulation s...
Altera_Forum's avatar
Altera_Forum
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11 years ago

I can only guess that the synth optimisations have removed your internal signal, and so then reading the output port is required - meaning it needs to be a buffer rather than output (in 1993 at least - this restriction is removed in 2008).

try using a syn_keep attribute on the output_signal