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Altera_Forum
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12 years ago

Help with latches but can't figure out why after several checks

Hi all can someone figure out why this code gives the following error in Quartus II (vs 13): It's about finite state machines with keys, ledG, ledR and 5 states (opened, closed, locked, unlock...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

There are cases in your code where LED_out retains the previous value.

To avoid latches you need to always give LED_out a value that depends only on the process inputs (state, key*).

If you need LED_out to have memory, make it a flip-flop.

Same for LED_R