The Smartest DIY Home Improvements

Table of Contents

Preface xi

About the Author xv

Introduction 1
Getting Started 2
Integrated Design Environment 3
Variables 8
Keywords 13
Array Keyword Summary 13
Collection Object Keyword Summary 15
Compiler Directive Keyword Summary 15
Control Flow Keyword Summary 15
Conversion Keyword Summary 20
String Manipulation Keyword Summary 21
Variables/Constants Keyword Summary 24
Operators Keyword Summary 26
Dates & Times Keyword Summary 28
Input & Output Keyword Summary 29
Directories & Files Keyword Summary 32
Miscellaneous Keyword Summary 33
Conclusion 34

Introduction 37
Serial Pin Out Description 40
Serial Interconnection 43
First Visual Basic Serial Port Examination Program 45
First Program 47
Second Serial Communication Program 56
General Purpose Serial Link 56
Conclusion/Exercise 76

Introduction 79
Ladder-Logic Programming 80
Micro PLC 82
MicroLogix PLC Memory Map 82
MicroLogix Instruction Set 85
Conclusion 91

Introduction 93
Ohm's Law 93
Interface Translators 95
Commercially Available Solid-State Converter Modules 98
Relays 98
Analog-Based Sensors 99
Conclusion 101

Introduction 103
The Protocol 103
Allen-Bradley Communication Packet Structure 106
Communication Packet Error Checking 107
Block Check Character (BCC) 107
Cyclic Redundancy Check (CRC) 108
Unprotected Write Command Structure 109
Unprotected Read Command Structure 111
Command/Response Exchange 112
First PLC Data-Acquisition Program 113
PLC Ladder Logic Requirements 114
Form Design 115
Form Controls 116
The Code 119
CRC Sub Procedure 120
Sub Form_Load0 Event Code 121
Sub Form_Unload0 Event Code 122
Animation of the Output-Status Lights 123
Animation of the Input-Status Lights 125
Communication Procedural Aspects 126
Conclusion/Exercise 135

Introduction 137
PLC Task & Interconnection Diagram 137
Ladder Logic Software 143

Introduction 153
Task Description 153
The Code 154
Conclusion/Exercise 178

Introduction 179
Task Description 179
The Code 187
Conclusion/Exercise 194

Introduction 195
Task Description 195
The Code 197
Conclusion/Exercise 204

Introduction 205
Task Description 205
The Code 206
Conclusion/Exercise 218

Introduction 219
Task Description 219
The Code 227
Sample Graph Screens 235
Conclusion/Exercise 240

Introduction 241
Task Description 241
The Code 245
Conclusion 255
Sample Display Pages 256

Introduction 259
Task Description 259
The Code 262
Conclusion/Exercise 266

Appendix 269
A Note on the Software 270
ASCII Table 271
Index 273