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Altera_Forum's avatar
Altera_Forum
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9 years ago

SignalTap II fails to acquire events

Hello, I'm using SignalTap II to debug and verify my Cyclone V SOC design. On the signal list there's an enumerated type VHDL FSM with 10 states. The FSM moves consecutively from one state ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
9 years ago

I think you sort of answered your own question. Since you're not using WHEN OTHERS, you may be getting into an unknown state for some reason. I don't know what's going on in each state, but you should pretty much always use WHEN OTHERS at the end of your state transition process and enable the "Safe State Machine" assignment in the Assignment Editor. What type of state encoding are you using? The default is one-hot, which can easily get into an unknown state if something is amiss.