15. Introduction to Tasks and Functions
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Tasks and functions are procedural blocks that allow code reusability, modularity, and better organization in Verilog designs. They encapsulate commonly used operations and can be called multiple times from different places in the code.
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Mainly, they are used to break larger code into smaller parts.
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Why Use Tasks and Functions?
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Code Reusability: Write once, use multiple times
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Modularity: Break complex operations into manageable pieces
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Readability: Make code cleaner and easier to understand
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Maintainability: Update logic in one place
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Testing: Isolate and test individual operations
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Tasks vs Functions - Quick Overview
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15.1. Function
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15.2. Task
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15.3. Static and Automatic Behavior
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15.4. Re-entrant Task and Function
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15.5. Advanced Techniques
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Comparison: Functions vs Tasks
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When to Use Each
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Use Function when:
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Computing a single return value
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Implementing combinational logic
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No timing delays needed
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Used in expressions or assignments
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Use Task when:
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Multiple outputs needed
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Timing controls required
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Testbench stimulus generation
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Complex sequential operations
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