Difficulty: Easy
Correct Answer: Incorrect
Explanation:
Introduction / Context:
Accurate VHDL syntax is essential for structural designs. Instances are labeled and associated with entities or components via a specific form that uses a colon, not a semicolon, and proper library/entity references. Misstating this leads to compilation errors and confusion about libraries and primitives.
Given Data / Assumptions:
Concept / Approach:
The correct syntax is label : entity library.entity_name (optional architecture), or label : component_name if using component declarations. The colon separates the instance label and the design unit being instantiated; a semicolon terminates the entire statement at the end, not between label and entity.
Step-by-Step Solution:
Write a label (e.g., u1).Place a colon then the entity or component name (e.g., u1 : entity work.foo).Provide generic map/port map associations.Terminate the statement with a semicolon after the port map, per VHDL syntax.
Verification / Alternative check:
Compile a small structural example; the compiler rejects the “label; entity …” form and accepts the “label : entity …” form.
Why Other Options Are Wrong:
“Correct” misstates the delimiter. The qualifiers about structural code or configurations do not change the colon requirement.
Common Pitfalls:
Forgetting library/USE clauses; mixing component and direct entity instantiation; misplacing the semicolon.
Final Answer:
Incorrect
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