Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Fitter ignores fast i/o assignments.

Why does fitter ignore the sdram fast i/o assignment? The warning is: Warning (176250): Ignoring invalid fast I/O register assignments. See the Ignored Assignments panel in the Fitter Compilatio...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Quartus can't promote registers to IO registers when:

for outputs: you read the output signal back in your logic

for inputs: you use both registered and unregistered inputs in your logic