VHDL

7

Subprograms and Overloading

CHAPTER OBJECTIVES

• Introduction to modular programming
• Subprograms—functions and procedures; defining and using them
• Differences between usage of functions and procedures
• Pure and impure functions
• Function overloading
• Operator overloading

7.1 INTRODUCTION

Function and procedures are collectively known as subprograms. Subprograms are sequential in nature just like a process statement. They support the modular programming approach, where a piece of code is intended of performing a particular function, or tasks are written as a general purpose code; and these modules are stored as procedure and procedures which can be called whenever and whereever needed. Although procedure and procedures are collectively known ...