Table of Contents ............................................................................................................................................... i

Table of Figures ............................................................................................................................................... xii

Chapter 1

Introduction ......................................................................................................................... 1

1.1

Revisions in this Manual ........................................................................................................... 2

1.2

PACSystems Programming and Configuration .................................................................. 3

1.3

Migrating Series 90 Applications to PACSystems ............................................................. 3

1.4

PACSystems Documentation ................................................................................................. 4

Chapter 2

Program Organization ....................................................................................................... 5

2.1

Structure of a PACSystems Application Program ............................................................. 6

2.1.1

Blocks................................................................................................................................................................................ 6

2.1.2

Functions and Function Blocks .............................................................................................................................. 6

2.1.3

How Blocks Are Called ............................................................................................................................................... 7

2.1.4

Nested Calls ................................................................................................................................................................... 7

2.1.5

Types of Blocks ............................................................................................................................................................. 8

2.1.6

Local Data .................................................................................................................................................................... 18

2.1.7

Parameter Passing Mechanisms ........................................................................................................................ 19

2.1.8

Languages .................................................................................................................................................................... 21

2.2

Controlling Program Execution ............................................................................................ 24

2.3

Interrupt-Driven Blocks ......................................................................................................... 25

2.3.1

Interrupt Handling .................................................................................................................................................... 26

2.3.2

Timed Interrupts ....................................................................................................................................................... 27

2.3.3

I/O Interrupts .............................................................................................................................................................. 27

2.3.4

Module Interrupts ..................................................................................................................................................... 27

2.3.5

Interrupt Block Scheduling .................................................................................................................................... 28

Chapter 3

Program Data ..................................................................................................................... 29

3.1

Variables .................................................................................................................................... 30

3.1.1

Mapped Variables ..................................................................................................................................................... 30

3.1.2

Symbolic Variables ................................................................................................................................................... 31

3.1.3

I/O Variables ............................................................................................................................................................... 32

3.1.4

Arrays ............................................................................................................................................................................ 34

3.1.5

Variable Indexes and Arrays ................................................................................................................................. 34

GFK-2950C

February 2018