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DL06 Micro PLC User Manual, 3rd Edition, Rev. E
x
Table of Contents
Chapter 7: RLL
PLUS
Stage Programming
Introduction to Stage Programming ........................................................................7–2
Overcoming “Stage Fright” ......................................................................................7–2
Learning to Draw State Transition Diagrams ........................................................... 7–3
Introduction to Process States ..................................................................................7–3
The Need for State Diagrams ...................................................................................7–3
A 2–State Process .....................................................................................................7–3
RLL Equivalent .......................................................................................................... 7–4
Stage Equivalent .......................................................................................................7–4
Let’s Compare .......................................................................................................... 7–5
Initial Stages .............................................................................................................7–5
What Stage Bits Do ..................................................................................................7–6
Stage Instruction Characteristics ...............................................................................7–6
Using the Stage Jump Instruction for State Transitions ..........................................7–7
Stage Jump, Set, and Reset Instructions ....................................................................7–7
Stage Program Example: Toggle On/Off Lamp Controller ......................................7–8
A 4–State Process .....................................................................................................7–8
Four Steps to Writing a Stage Program ...................................................................7–9
1. Write a Word Description of the application. .......................................................7–9
2. Draw the Block Diagram. .....................................................................................7–9
3. Draw the State Transition Diagram. .....................................................................7–9
4. Write the Stage Program. .....................................................................................7–9
Stage Program Example: A Garage Door Opener ..................................................7–10
Garage Door Opener Example ...............................................................................7–10
Draw the Block Diagram ........................................................................................7–10
Draw the State Diagram .........................................................................................7–11
Add Safety Light Feature ........................................................................................7–12
Modify the Block Diagram and State Diagram .......................................................7–12
Using a Timer Inside a Stage ..................................................................................7–13
Add Emergency Stop Feature .................................................................................7–14
Exclusive Transitions ............................................................................................... 7–14
Stage Program Design Considerations ................................................................... 7–15
Stage Program Organization ..................................................................................7–15
How Instructions Work Inside Stages ...................................................................... 7–16
Using a Stage as a Supervisory Process ................................................................... 7–17