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Mastering PLC Programming

You're reading from   Mastering PLC Programming The software engineering survival guide to automation programming

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Product type Paperback
Published in Mar 2023
Publisher Packt
ISBN-13 9781804612880
Length 386 pages
Edition 1st Edition
Tools
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Author (1):
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M. T. White M. T. White
Author Profile Icon M. T. White
M. T. White
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Toc

Table of Contents (25) Chapters Close

Preface 1. Part 1 – An Introduction to Advanced PLC Programming
2. Chapter 1: Software Engineering for PLCs FREE CHAPTER 3. Chapter 2: Advanced Structured Text — Programming a PLC in Easy-to-Read English 4. Chapter 3: Debugging — Making Your Code Work 5. Chapter 4: Complex Variable Declaration — Using Variables to Their Fullest 6. Part 2 – Modularity and Objects
7. Chapter 5: Functions — Making Code Modular and Maintainable 8. Chapter 6: Object-Oriented Programming — Reducing, Reusing, and Recycling Code 9. Chapter 7: OOP — The Power of Objects 10. Part 3 – Software Engineering for PLCs
11. Chapter 8: Libraries — Write Once, Use Anywhere 12. Chapter 9: The SDLC — Navigating the SDLC to Create Great Code 13. Chapter 10: Advanced Coding — Using SOLID to Make Solid Code 14. Part 4 – HMIs and Alarms
15. Chapter 11: HMIs — UIs for PLCs 16. Chapter 12: Industrial Controls — User Inputs and Outputs 17. Chapter 13: Layouts — Making HMIs User-Friendly 18. Chapter 14: Alarms — Avoiding Catastrophic Issues with Alarms 19. Part 5 – Final Project and Thoughts
20. Chapter 15: Putting It All Together — The Final Project 21. Chapter 16: Distributed Control Systems, PLCs, and Networking 22. Assessments 23. Index 24. Other Books You May Enjoy

Auto declaring variables

In the previous chapters, we manually created variables. Manually creating variables is a common way of creating variables, but it is not the only way. CODESYS offers a simple tool for declaring variables called an Auto Declare tool. The tool is useful for declaring variables with data types that you may not be familiar with, creating a variable in a different file, and so on. The tool is also handy for assigning actual outputs, comments, and more for the variable.

The purpose of this tool is to help assist you in the creation of variables. However, this tool can easily be more trouble than it is worth. For the most part, it will be easier to declare a regular variable as we have been doing so far – that is, simply using the editor to write the variable’s code manually. However, if something is complex, in a different file, or you simply forgot the syntax, the tool can be of great value. In short, use the tool wisely and when necessary.

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