Book Image

Mastering PLC Programming

By : Mason White
Book Image

Mastering PLC Programming

By: Mason White

Overview of this book

Object-oriented programming (OOP) is a new feature of PLC programming that has taken the automation world by storm. This book provides you with the necessary skills to succeed in the modern automation programming environment. The book is designed in a way to take you through advanced topics such as OOP design, SOLID programming, the software development lifecycle (SDLC), library design, HMI development, general software engineering practices, and more. To hone your programming skills, each chapter has a simulated real-world project that’ll enable you to apply the skills you’ve learned. In all, this book not only covers complex PLC programming topics, but it also removes the financial barrier that comes with most books as all examples utilize free software. This means that to follow along, you DO NOT need to purchase any PLC hardware or software. By the end of this PLC book, you will have what it takes to create long-lasting codebases for any modern automation project.
Table of Contents (25 chapters)
1
Part 1 – An Introduction to Advanced PLC Programming
6
Part 2 – Modularity and Objects
10
Part 3 – Software Engineering for PLCs
14
Part 4 – HMIs and Alarms
19
Part 5 – Final Project and Thoughts

Chapter 5: Functions — Making Code Modular and Maintainable

  1. A function is a callable block of code that provides modularity to a program, can accept parameters/arguments, and will only run when invoked.
  2. Arguments that are pre-assigned and do not need to be provided when the function is called.
  3. A parameter that is assigned a value when the function is called based on its name.
  4. The function’s parameters, return type, and other attributes that distinguish it.
  5. By default in a one-to-one fashion.
  6. Any amount of code as long as the code’s intended purpose can be described in one sentence without the word and.
  7. The type of value the function will return.
  8. Technically yes, depending on the system. However, certain return types cannot be assigned to certain variables.