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15. Introduction to Tasks and Functions

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.

Mainly, they are used to break larger code into smaller parts.

Why Use Tasks and Functions?

Code Reusability: Write once, use multiple times

Modularity: Break complex operations into manageable pieces

Readability: Make code cleaner and easier to understand

Maintainability: Update logic in one place

Testing: Isolate and test individual operations

Tasks vs Functions - Quick Overview

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15.1. Function

15.2. Task

15.3. Static and Automatic Behavior

15.4. Re-entrant Task and Function

15.5. Advanced Techniques

Comparison: Functions vs Tasks

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When to Use Each

Use Function when:
- Computing a single return value
- Implementing combinational logic
- No timing delays needed
- Used in expressions or assignments

Use Task when:
- Multiple outputs needed
- Timing controls required
- Testbench stimulus generation
- Complex sequential operations

Advanced Generate technique

Function

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