vhdl code compilation error code

why not read what the error says and fix it? They are usually quite helpful

Otherwise, unless you post the code and error, we will have no idea.

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when I compile my vhdl code one error code pop up top level FSM undefined what does this error code mean what should I do?

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Apologies if jump the wagon but I know this error could be due to FSM module not added to project files.

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top level FSM undefined

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It means that the top level entity name set in your Quartus project can't be found in any of the project files. Besides not adding a file to the project it's mostly brought up by using different names. E.g. you saved a file under a different name and set it as project top. Quartus changes the top entity name then to the new file name, wheter an entity of this name can be found in the file or not.