TwinCAT IEC61131-3

26.07.20071

TwinCAT IEC61131-3

26.07.20072

Overview

Contents

Part 1IEC 61131-3 Overview

Software model

Identifier

Elementary data types

Variables classes

Block types

TwinCAT System Service

Timing

Part 2

Variables II Structs, Enums

Variables II Arrays

Checkbounds

Structured text

Part 3

Sequential Function Chart

Step diagnosis

Appendix

Bootprojects, Data remanence

Checker functions

Example Step by Step

26.07.20073

The IEC 61131-3

IEC 61131-3

-1 General definitions and

typical function (cyclic processing,

process image input and output)

-2 Environmental conditions and conditioning classes

of the control and the programming devices.

(temperature, air humidity)

-3

Rules for using and implementation of

PLC programming languages

-4 Guide line for the system analysis of the user, the

system selection, the realisation of the

application, as well as maintenance and

servicing

-5Definition of the

communication via funcion blocks and communication via

access paths

(additionally to –3)

-6 Communication via

fieldbus.

-7 Fuzzy systems in the

PLC

26.07.20074

Standard guide

The PLCopen contains 3 devaluation compatible compli ance classes:

Base level

Portability level

Full compliance level

Contains IL, ST, SFC, CFC (in preparation) a few data types, standard operators,

functions, function blocks as well as local variables

Data exchange format (8 bit ASCII). Data types with 32 bit strings, Arrays and all functions and operators based on this

data type.

Here the supreme compatibility degree must exist.

26.07.20075

Functional structure of a PLC

Power supply

Communicationfunction

MMI functions

Check functions

Power supply system Operator Programmer

Executing function

Operating system

Operating program

Data

Interface function to sensors and actuators

Signal executing function

Other systems

process

26.07.20076

Communication functions

Communicationfunction

MMI functions

Check functions

Operator

Programmer

Other systems

ADS/AMS router

Ethernet, RS232, Modem

Server

ADS OCX, ADS DLL, TwinCAT OPC

Forcen, Breakpoints, single step, System

Manager, Scope View

26.07.20077


Operating function

Operating system

Operating program

Data


Win NT, 2000, XP

PLC Server 1, PLC Server 2, PLC Server 3, PLC Server 4,

NC Server, Cam Server

ADS-, I/O processimage

Compiled PLC project, selfdefined server

26.07.20078

Interface function between sensors and actuators

Interface function between sensors and actuators

Copy rule DP RAM <-> PA PLC

Actuators and sensors

A E

F-Field-Device

DP/PA

F-ActuatorF-Sensor

26.07.20079

Overview

Contents


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200710

Software model

Configuration

Main Motion

Resource Resource

Task1 Task2 Task1 Task2

Program Program Program Program

FB FB FB FB FB

Global and direct addressed variable

access paths

26.07.200711

Software model Example

Configuration

Main Motion

Resource PC Resource BC9000

Task1 Task2 Task1

Program Program Program

FB FB FB FB

Global and direct addressed variable

Mapping in the TwinCAT System Manager

access paths

Example PC PLC with 1 run time und zwei Task 1 BC900 ( Ethernet Controller)

26.07.200712

Overview

Contents


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200713

Identifier

Identifier serves to the individual name assignment for variables, data types, functions...

• The identifier begins with a letter or a underscore

• Followed by numbers, letters and underscore

• No difference between capital letters and small let ters

• Blank character

• Sequential underscores

• mutated vowel

Not allowed

• Special characters (!,“,§,$..)

26.07.200714

Prefix

b – Boolean r – Real s - String ST_ - Declaration of structures st - Initialisation of structuresFB_ - Declaration of function blocksfb – Initialisation of function blocks M_ - Declaration of methods

bEndschalterLinksrSollPositionsRxDaten

ST_MotorDaten (declaration)stM1Parameter (instance)

FB_Ueberlast (declaration)fbM1Ueberlast (instance)

Hungarian notation: Write part words together. The f irst letter of a part word must be a capital letter.

Prefixes are not specificated, but they make the ha ndling of the identifier easier. Here some suggestions:

26.07.200715

Key words and comments

Key words are preset indentifer by the IEC61131-3.They are fixed components of the syntax and must not be used for other purposes.

TRUE, FALSE, AND, FUNCTION,...

Using the option Auto format, the keywords are written in capital letters.

The comments are limited with the characters (* at the beginning and *)at the end.Comments can be placed there, where blank characters are allowed.Exception: inside character string literals.

(*digital inputs*)bStart AT%IX0.0:BOOL;(*Machine start*)

(*analog inputs*)TemK1 AT%IW10(*Byte 10-11*): WORD;

26.07.200716

Overview

Contents


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200717

Data types

Data types describe memory locations resp. appoint the ir features.

Type value

(Part)STRING

µ

SINT -75

USINT 181

Memory 1 0 1 1 0 1 0 1

Value type (WORD) Data width (2 Byte)Initial value (0)Value range (0..65535)

26.07.200718


Type ANY-Type Key word Data width(Bit)

Initial Value range

Boolean ANY_Bit BOOL 1 FALSE TRUE/FALSE

Bit string(8) BYTE 8 0 0..16#FF

Bit string(16) WORD 16 0 0..16#FFFF

Bit string(32) DWORD 32 0 0..16#FFFF_FFFF

Short integer ANY_Num SINT 8 0 -27...27-1

Integer INT 16 0 -215...215-1

Double integer DINT 32 0 -231...231-1

Unsigned short integer USINT 8 0 0...28-1

Unsigned integer UINT 16 0 0...216-1

Unsigned double integer UDINT 32 0 0...232-1

26.07.200719


Type ANY-Type Key word Data width(Bit)

Initial Value range

Slide point ANY_Real REAL 32 0.0 -1.18*10-38.. 3.4*1038

Long slide point LREAL 64 0.0 -2.22*10-308.. 1.798*10308

Date ANY_Date DATE (D) 32 D#1970-01-01

Time of day TIME_OF_DAY (TOD)

32 TOD#00:00 TOD#00:00..TOD#23:59

Date time of day

DATE_AND_TIME(DT)

32 DT#1970-01-01-00:00

time ANY_Time TIME 32 T#0ms

Sequential characters

ANY_String STRING (80+1)*8 ‚‘

26.07.200720

String

A STRING type variable can contain any string of characters. The size entry in the declaration determines how much memory space should be reserved for the variable. It refers to the number of characters in the string and can be placed in parentheses or square brackets. If no size specification is given, the default size of 80 characters will be used.

Strings are zero terminated, that means the last

character of a string is always zero. Each character

inside a string needs one byte.

VAR

strVar : STRING(3);

lenVar: INT;

sizeVar: INT;

END_VAR

VAR

strVar : STRING(3);

lenVar: INT;

sizeVar: INT;

END_VAR

26.07.200721

Special characters

If you want to add a special character into a string, you have to begin with a $-

character.

character description

$$ dollar signs

$‘ Single quotation mark

$L or $l Line feed

$N or $n New line

$P or $p Page feed

$R or $r Line break

$T or $t Tab

ACR100 (*Str. Abschluss*)

Special Characters

26.07.200722

ASCII <-> CHR

If a character in a program ought to be converted to an ASCII character, two procedures are allowed:

1. Indirectly, by interpreting the data memory different.

2. Directly via the provided function block. ASC and CHR are both included in the libraryChrAsc.lib.

(Component of the Comlib)

26.07.200723

Variables declaration el. data types

A variable owns a name, behind which a value (numbe r, string, date) hides. The name of the variable is a way description to th e declared data.Variables distinguish themselves thereby, that thei r content can be changed to the run time.

bStellerUntenLinks: BOOL:=TRUE;

Identifier Data type Initial value

The physical logical storage location of the variable is not

known by the operator(unlocated)

The degrees of freedom and the restrictions at the assignment of the identifiers can be seen

on the slides identifier and prefixes.

26.07.200724

Variables declaration el. data types

At the declaration of the variables it´s possible t o link the name with an explicit specified address. For the mapping of the inputs and outputs to the symbolic variables, the locating of variables is es sential.

bStellerUntenLinks AT%IX0.0:BOOL:=TRUE;

Identifier AT Address : Data type ;

%I

%Q

%M

ATIdentifier X

B

W

D

Byte Data type

Byte

Bit

These variables own a unique address (located)

From TwinCAT 2.8 the addressing can be done automati cally. Then the program works with not completely located variables.

bStellerUntenLinks AT%I*:BOOL:=TRUE;

26.07.200725

Overview

Contents


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200726

Validity range

Local variables are limited on the block, in which they were declared.

Global variables are known in each block inside a project.

Key words

VAR ..

END_VARVAR_INPUT ..

END_VARVAR_IN_OUT ..

END_VARVAR_OUTPUT ..

END_VAR

Key words

VAR_GLOBAL ..

END_VARVAR_CONFIG ..

END_VAR

26.07.200727

Access via the located variables

PROGRAM A

VAR

END_VAR

PROGRAM B

VARlocVar AT%MB2:WORD;END_VAR

LD %MB2

�

�

�

�

�

�

Project Machine

From program A is a direct access by address %MB2 to the local declared variable ‚locVar‘ in program B possible.

26.07.200728

Overlapping in the validity range

PROGRAM A

VARVar1 :WORD;

END_VAR

LD Var1

�

�

Project Machine

VAR_GLOBALVar1:WORD;

END_VAR

As shown in the example on the left, there is an overlapping in the validity range.In this case, the local declared variable Var1 is loaded into the accumulator.

The compiler generates no warning for this overlapping.

26.07.200729

Attributes

Attributes can be used to define special features o f variables.

Examples:

The variable(s) should be stored at the shutdown of the PLC, to be reloaded at the new start.

VAR RETAIN

Zaehler: UINT;

END_VAR

VAR PERSISTENT

Zaehler: UINT;

END_VAR

Initial values, the variables should be allocated wi th a special value at the PLC start or reset.

VAR

AccelerationTime : TIME := T#3s200ms;

END_VAR

26.07.200730

Attributes (constants)

If you want to use a mathematic, construction, or machine constant, you have to complete the regular key words VAR_GLOBAL .. END_VAR with the key word CONSTANT. This completement can also be used with local keywords. The state of these identifier is read.

VAR_GLOBAL CONSTANTpi: REAL:=3.141592654;

END_VAR

PROGRAM AVAR CONSTANT

�

END_VAR

�

�

�

Projekt Maschine

VAR_GLOBAL CONSTANT

�

END_VAR

26.07.200731

Overview

Contents


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200732

POU program organisation units

In the IEC61131-3 exists under the main generic ter m three POUs:

� Programs

� Function blocks

� Functions

The organisation POU is replaced by the task configurator.

The data POUs are replaced by multi-dimensional fie lds (ARRAY‘s).

26.07.200733

POU program organisation units

Each POU consists of a declaration part and a body.

The declaration part is the same in each IEC progra mming language. The local variables of the block are declared there.

The body is written in one of the IEC programming l anguages which include IL, ST, SFC, FBD, LD or CFC.

26.07.200734

PROGRAM PRG

Program PRG

• Call by a task (TwinCAT: One programm calls another)

• calls : FB‘s, Functions, (Programs)

• Local variable : static, i.e. the local data are av ailable at the next cycle.

• Inputs: mostly 0, but VAR_INPUT possible

• Outputs: mostlys 0, but VAR_OUTPUT possible

• Transfer by reference: VAR_IN_OUT also possible

• Debug: The local data are directly visible in the o nline mode of the PLC Control

• Using: Main programms, main, hand, automatic....

26.07.200735

Function block FB

Function block FB

• Called by programs or other FB´s

• calls : FB‘s, functions,

• Locale variable : static, i.e. the local data are a gain available at the next cycle. At multiple call multiple instances (mul itply). Each FB call can have own local data.

• Inputs: 0,1,2,3 VAR_INPUT

• Outputs: 0,1,2,3 VAR_OUTPUT

• Transfer by reference 0,1,2,3 VAR_IN_OUT

• Debug: In the online mode of PLC Control, the insta nce of the according call has to declared. After this, the loc al data are visible for each call.

• Using: multiple used function blocks, which need an own data range each. Multiple sequences....

26.07.200736

Create an instance

FUNCTION_BLOCK AVAR _INPUT

Var_IN :WORD;END_VARVAR _OUTPUT

Var_Out :BYTE;END_VARVAR

Var1 :WORD;Instanz_1: B;

END_VAR

LD Var1CAL Instanz_1

FB

PROGRAM MAINVAR

Instanz_1 :A;Instanz_2 :A;Instanz_3 :B;

END_VAR

CAL Instanz_1CAL Instanz_3

PRG Instanz_1Var_In : WORD; Var_Out : BYTE; Var_1:WORD;Instanz_1

X :REAL; Y :REAL;

Instanz_2Var_In : WORD; Var_Out : BYTE; Var_1:WORD;Instanz_1

X :REAL; Y :REAL;

Instanz_3X :REAL; Y :REAL;

FUNCTION_BLOCK B VAR_INPUT

X :REAL;END_VARVAR _OUTPUT

Y :REAL;END_VAR

�

FB

26.07.200737

Function FC

Function FC

• called by: programs, function blocks and other func tions

• calls: functions

• Local variable : temporary, i.e. the local data are only available for the operating time of the function. Afterwards this data range is used by other functions.

• Inputs: 1,2,3........ VAR_INPUT

• Outputs: exactly 1!, but structure varaibale possible . The output name is at the same time the name of the function.

• Except for TwinCAT: VAR_IN_OUT possible,

• Debug: The local variables are visible with „???“ in t he online mode of PLC Control, because these variables are multiple u sed by all functions in the cycle, and the monitoring (debug) takes place at the cycle bounds. Hepl: program development with breakpo intsBreakpoints

• Using: algorithms, at which the result is available after a pass.Scaling, compare......

26.07.200738

FC Specials

From TwinCAT 2.8: The return value can be defined directly if a new function is created.From TwinCAT 2.8: The return value can be defined directly if a new function is created.

Function nameFunction nameReturn value

The name of the „output“ is scale.

Scale can be used as local variable inside the

function(Write/Read)

Return value

The name of the „output“ is scale.

Scale can be used as local variable inside the

function(Write/Read)

InputsInputs

Local variables are only valid for the operating

time of the function

Local variables are only valid for the operating

time of the function

26.07.200739

Overview

Contents


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200740


The TwinCAT System Service operates as Windows NT service in the local system account. In this way, t he

TwinCAT System Service is started by Windows NT bef ore a user has logged on. As an activity symbol, the Tw inCAT System Service incorporates its icon into the task bar of the desktop. In addition, the colour of the icon in dicates

the state of the TwinCAT system.

The TwinCAT System Service is primarily responsible for starting and stopping the

TwinCAT run time system. It loads all configured servers and initialises them during the TwinCAT

system start.

.

TwinCAT stopped

TwinCAT starting.

TwinCAT running.

TwinCAT Config Mode

26.07.200741


The TwinCAT I/O subsystem can be reset via the TwinCAT System Service. For this, the

corresponding function must be selected in the context menu. The reset applies to all

connected field bus systems.

The event display is a programm to moniotor the events in the system. The event logging service starts automatically, if you execute Windows NT.

26.07.200742

Multitasking

TwinCAT possesses more than 62 different tasks. The default settings can use preset profiles or change the priority individu ally.

26.07.200743

Assigning the computing power

Real time operation of PLC software in the classical PLC.

Read inputs

Write outputs

Operate program

PLC cycle PLC cycle t

tPLC cycle PLC cycle

Win NT & HMI Interface

Real time operation of PLC software (1 task) on a PC w ith windows NT.

26.07.200744

Overview

Contents


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200745

Real time

Many industrial applications demand a guarantee, th at, clearly predictable and reproduceable, the system load reacts sufficient fa st to the process event in a defined time.

The real time is very important for the digital con trol. The sampling of an analog signal (actual position) with a PC should have abso lute constant distances between two measurements.

Each part process requires different reaction times . Because of this, several part processes with different features and different rea ction times can be created in one automation task.

If several tasks want to access the CPU simultaneou sly, the IEC 61131-3 defines two procedures:

1. Preemptive (interruptible execution) multi taski ng (TwinCAT)

2. Non preemptive (not interruptible execution) mul ti tasking

26.07.200746

Real time operation

� The real time operation will be achieved with deterministic time slices. The width of the time sl ices can be chosen in steps: (1000µs ... 50µs).The default setting is 1ms.

� With the begin of a new time slice, the software devices (PLC, NC) will be executed with priority control.

� The time slices will be kept with an accuracy of±±±± 15µs (Jitter). Device with the lowest priority goes to the waiting loop and waits until the CPU is free.

- 15µs +15µs

26.07.200747

Real time

The TwinCAT real-time system can be configured via the context menu of the TwinCAT System

Service.

Length of the time slice

Processor time can be assigned to the TwinCAT real-time system via the linear regulator in the figure above. On a time basis of 1 ms, this means that TwinCAT has a maximum of 800µs available each milli-second.

When the TwinCAT real-time system switches to its idle task, the processor is returned to Windows NT. The bar in the linear regulator dis-plays the current utilisation level of the real-time system. The display is averaged over 256 cycles (ms).

In this case, the current and maximum latency times in the real-time sys-tem are shown. The time by which the central system tick arrives t oo late is measured.

26.07.200748

Real time operation

� Cyclic PLC task e.g. 10ms

10ms 20ms 30ms40ms0ms

� Refinement: Behavior under TwinCAT base cycle 1 ms

0ms 1ms

80%

TwinCAT W

2ms

80%

TC W

3ms

80%

W

PLC PLC

Time slice forWindows

Time slice for TwinCAT

PLC programcyclic task

If TwinCAT does not need the (full) reserved time s lice, the scheduler provides this computing power to windows.

26.07.200749

Real time operation

� PLC tasks and drive control will be executed determ inistically with multiple tasking.

Real time operation of a PLC program and NC control with a PC

SPS cycle (e.g. 2ms) PLC cyclet

tNC cycle (e.g. 1ms) NC cycle NC cycle NC cycle

1ms 2ms 3ms 4ms 5mse.g.:

NC PLC program

Win NT & HMI Interface

1 2 3 41 2 31‘ 2‘

26.07.200750

Real time operation

� The smaller the time slice, the shorter the reaction time of the highest priority task.

� This has the consequence that the software devices must be fairly often interrupted.

� If a device is interrupted, the program stack has t o be safed. This has the consequence that the recopy expense rises.

� TwinCAT and the operating system are equal.

� For the operating system, calculating capacity is g iven regularly.

� The switch to the operating system takes place at t he earliest, as soon as all TwinCAT devices complete the processing, and at the latest at the CPU limit.

26.07.200751

Task + POU´s -> Create a new project

Before a new project starts, the following question s have to be checked:

1. What is the target platform, i.e. the device the user wants his program to run.

TwinCAT offers three different platforms.

Soft SPS (IPC)

Hard SPS (BCXXX0)

26.07.200752

Create a new project

2. In which distances and under which circumstances shall the PLC program be processed?

The IEC 61131-3 defines the task as a element of th e execution control, which is able to call several programs to execute.

At the configuration of the task one of the variant s „cyclic“ and „event“ can be chosen. TwinCAT only supports the „cyclic“ vari ant.

It´s possible to create an event driven task from a cyclic task. For this, the

program call must depend on an event.

26.07.200753

Create a new project

The task name is an identifier. Respectively the rules for the identifier obtain.

Priority of the task. The value range (0-3) is an offset on the default value 25 for the first run time. Each run time possess maximum

to four different tasks.

The interval time is always a multiple of the time slice.

26.07.200754

PLC Control Symbol bar

File

new

open

safe

Project

Start

Stop

Single step

Breakpoint

Log in

Log off

Element

Cut

Copy

Insert

Find

Find next

The field for the variables depends on the selected IEC

language.

PLC Control

26.07.200755

Main program

� The task is a trigger mechansim. A program is required to execute logical operations.

�The task calls one program. If an instance of a function block is needed, it can only be called from a program.

The features of an POU can be defined with this dia log.

�The name is an identifier. Respectively the rules for the ide ntifier obtain.

� The type of the POU depends on the problem.

� The language of the POU should be used according to the problem.

26.07.200756

Program

A program is a POU which returns several values dur ing operation. Programs are recognized globally throughout the project. All values are retained from the last time the program was run until the next.

Programs can be called by programs and function blocks.

A program call in a function is not allowed.

If a POU calls a program, and if thereby values of the program are changed, then these changes are retained the next time the p rogram is called, even if the program has been called from within another POU.

26.07.200757

Overview

Contents

Part 1

IEC 61131-3 Overview

Software model

Identifier


Variables classes

Block types


Timing

Part 2Variables II Structs, Enums

Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200758

Derivated data types (Variable II)

The user can create own data types on the base of e lementary data types or already created data types. The new created data ty pes are visible in the whole project.They begin with the keyword TYPE and end with END_TY PE.

Parent typeName Data type Initial value Range

DerivationName Data type Initial value

heir

New value

Range

26.07.200759

References (Alias Types) (Variable II)

You can use the user-defined reference data type to create an alternative name for a variable, constant or function block. Create your references as objects in the Object Organizer under the register card Data types.

They begin with the keyword TYPE and end with END_TYPE.

Syntax:

TYPE

<Identifier>:<Assignment term>;

END_TYPE

Example: Ads_Net_ID

TYPE

Net_ID:STRING(23);

END_TYPE

26.07.200760

Enumeration (Variable II)

Enumeration is a user-defined data type that is mad e up of a number of string constants. These constants are referred to as enume ration values. Enumeration values are recognized in all areas of t he project even if they were locally declared within aPOU. It is best to create your enumerations as objects in the Object Organizer under the register card Dat a types. They begin with the keyword TYPE and end with END_TYPE.

Syntax:TYPE <Bezeichner>:(<Enum_0> ,<Enum_1>, ...,<Enum_n>);END_TYPE

Beispiel:TYPE Woche:(Mo, Di, Mi, Dn, Fr, Sa, So:=10); (*Mo = 0 Di = 1..

.. Sa = 6 So = 10*)END_TYPE

TYPE Richtung:(Up, Dn);(*Up = 0 Dn = 1*)END_TYPE

You may not use the same enumeration

value more than once.

26.07.200761

Enumeration (Variable II)

The <Identifier> can take on one of the enumeration values and will be initialized with the first one. These values are co mpatible with whole numbers which means that you can perform operations with th em just as you would with INT. You can assign a number x to the <Identif ier>. If the enumeration values are not initialized, counting will begin wit h 0. When initializing, make certain the initial values are increasing. The vali dity of the number will be reviewed at the time it is run.

VARWochenTag:Woche;

END_VAR

WochenTag:=3;

26.07.200762

Structure declaration (Variable II)

Pers_Data

Name: Firstname:

Age: Address:

form

TYPE Pers_Data :STRUCT

Name: STRING(25);Firstname: STRING(25);Age: USINT; Address: STRING(55);

END_STRUCTEND_TYPE

Identifier for the new data type

Identifier : parents data type

■

■

■

Structures are self defined data types.They are important aids for managing the process data.

Furthermore the structures are suited for capsulated data transfer to function blocks.

Structures can be used like single element variables.

26.07.200763

Structures Instances (Variable II)

P1

P3

K2

VARP1, P3 : Pers_Data;

END_VARVAR_OUTPUT

K2 : Pers_Data; END_VAR

VAR_INPUTEmployees : Pers_Data;

END_VAR

P1Name:=‚Müller‘ Firstname:=‚Peter‘Age:=32Address:=‚Postweg 34‘

P3Name:=‚Koschnik‘ Firstname:=‚Heinz‘Age:=37Address:=‚Domplatz 10‘

Name_total:= CONCAT(P3.Firstname, P3.Name)(*Heinz Koschnik*)■

■

26.07.200764

Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing


Variables II Arrays

Checkbounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200765

Arrays (Variable II)

Arrays describe lists resp. data arrays. All elemen ts in the arrays are from the same type. Arrays can also exist of own data types (stru ctures).

One- , two-, and three-dimensional arrays are possib le.

VARFeld_1 : ARRAY[1..10] OF BYTE; one-dimensional

Feld_2 : ARRAY[1..10, 2..5] OF UINT; two-dimensional Feld_3 :ARRAY[1..10] OF DINT; three-dimensional

END_VAR

� It´s possible to put a data array to a direct addre ssed memory position

VARFeld_1 AT%MB100:ARRAY[1..10] OF BYTE;

END_VAR

�Access to the sub-elements of a data arrayFeld_1[2] := 120; (* explicit access*)Feld_2[i,j] := EXPT(i,j); (*indicated access*)

26.07.200766

Array one-dimensional example with initialisation (Variable II)

One-dimensional

DBZeiten : ARRAY [0..6] OF TIME:= T#1s, T#2s, T#1s, 4(T#0s);

Identifier Field Data type Initial value

The field length can be done explicit or with the

aid of constants.

A dynamic change of the field size is not

possible.

Faktor Wert

0 1 2 3 4 5 6

T#1s T#2s T#1s T#0s T#0s T#0s T#0s

Access:VAR

WertAusArray : TIME;

END_VAR

WertAusArray := DBZeiten[1];

26.07.200767

Array two-dimensional example with initialisation (Variable II)

To assign for example support points, an array is w ell qualified.

Supportpoint: ARRAY [0..1, 0..6] OF REAL:= 0, 1.7, 2, 4(3.33), 6, 6(1.2);

Identifier Field Data type Initial value

Factor Value

0 1 2 3 4 5 6

0 0 1.7 2 3.33 3.33 3.33 3.33

1 6 1.2 1.2 1.2 1.2 1.2 1.2

Access:VAR

WertAusArray : REAL;

END_VAR

WertAusArray := Supportpoint[1 ,0];

26.07.200768

Array initialisation more clearly with comments (Variable II)

Example: Drive jobs for an axis

Drivejob: ARRAY [0..3, 0..1] OF LREAL :=

(* target position, velocity *)

(*Job 0*) 20.0, 30.0,

(*Job 1*) 33.75, 30.0,

(*Job 2*) 45.0, 30.0,

(*Job 3*) 70.75, 30.0;

26.07.200769

Array three-dimensional example with initialisation (Variable II)

Supportpoint : ARRAY [0..2, 0..1, 0..2] OF UINT:= 0,1,2,3,4,5,

10,11,12,13,14,15,

20,21,22,23,24,25

Identifier Array Datatype Initial value

Access:VAR

ValfromArray : UINT;

END_VAR

ValfromArray :=

Supportpoint[ 2,0,1 ];

0 1 2

3 4 5

0 1 2

0

1

0

10 11 12

13 14 15

0 1 2

0

1

1

20 21 22

23 24 25

0 1 2

0

1

2

26.07.200770

Exceed bounds (Variable II)

A dangerous state can arise in the PLC program, if an access to a range outside the data field takes place.

VARFeld_1 : ARRAY[1..10] OF BYTE;Feld_2 : ARRAY[1..10, 2..5] OF UINT;Feld_3 : ARRAY[1..10] OF DINT;

END_VAR

i:= 9 9Feld_1[i+2] := 120;

�

�

Feld_1[9]; 0

Feld_2[1,2]; 120

26.07.200771

Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing


Variables II Arrays

Check bounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200772

Check Bounds (FUN)

If you define a function in your project with the name CheckBounds, you can automatically check for out-of-range errors in arrays.

iMinMax

Limited value

FUNCTION CheckBounds :INT

VAR_INPUT

I,L,U : INT;

END_VAR

IF I< L THEN

CheckBounds := L;

ELSIF I > U THEN

CheckBounds := U;

ELSE

CheckBounds := I;

END_IF

Error case

Error case

„OK“ case

26.07.200773

Inserting Check Bounds 1(FUN)

CheckBounds can be copied with „Copy Project“ from a nother PLC project to the current project ( e.g. training project). Check bounds can also be created or written directley.

26.07.200774

Inserting Check Bounds 2(FUN)

So that CheckBounds is recognised by translating, th e following may NOT be changed:

-Name and type of the inputs I,L and U

-Name (CheckBounds) and return value (INT).

-In the function can be edited freely. At application of own local variables (e. g. error counter, instances of FBs) is to be considered that these are o nly temporary (at functions). Such a variable has to be declared (in this case) under the global variables.

26.07.200775

Check Bounds (FUN) mode of operation


VAR_INPUT

I,L,U : INT;

END_VAR

IF I< L THEN

CheckBounds := L;

ELSIF I > U THEN

CheckBounds := U;

ELSE

CheckBounds := I;

END_IF

Program (* User*)VAR arrVar:ARRAY[0..3] OF INT index :INTEND_VAR

index:=2;

arrVar[Checkbounds[2,0,3]:=100;

index:=index+2

arrVar[Checkbounds[4,0,3]:=100;

Access at 2->ok

Automatical call


VAR_INPUT

I,L,U : INT;

END_VAR

IF I< L THEN

CheckBounds := L;

ELSIF I > U THEN

CheckBounds := U;ELSE

CheckBounds := I;

END_IF

Checkbounds returns 3, the

access is

limited to the maximum

index

26.07.200776

Note: Further Checker functions

From TwinCAT 2.8 the following further Checker functio ns are possible:

Check division by 0

CheckDivByte

CheckDivWord

CheckDivDWord

CheckDivReal

Check value range

CheckRangeSigned

CheckRangeUnsigned

(see Appendix)

26.07.200777

Combination Structures and Arrays (1)

An array can consist of structures:

Structure:TYPE DrillPos :STRUCT

XPos: LREAL;FeedrateX: LREAL;AccelerationX: LREAL;DeccelerationX: LREAL;JerkX: LREAL;YPos: LREAL;FeedrateY: LREAL;AcceleartionY: LREAL;DeccelerationY: LREAL;JerkY: LREAL;FeedDrill: LREAL;Kuehlen: BOOL; (*Pump ?*)

END_STRUCTEND_TYPE

Declaration of the arrays :

Positions :ARRAY[0..100] OF DrillPos;

26.07.200778

Combination Structures and Arrays (1)

�Access to „Drillpos 55“:

�Access:MoveXAx (* FB Instance*)

(Execute:= TRUE,Position:= Positions[55].XPos ,Velocity:= Positions[55].FeedrateXAcceleration:= Positions[55].AccelerationX,Deceleration:= Positions[55].DeccelerationX,Jerk:= Positions[55].JerkX,Direction:= .........,Axis:= .............,);

26.07.200779

Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing


Variables II Arrays

Check bounds

Structured text

Part 3


Step diagnosis

Appendix


Checker functions


26.07.200780

ST Structured Text operators in the order of their binding strength:

Operation

Put in parenthesesFunction callExponentiationNegateBuild. complementsMultiplyDivideModuloAddSubstractCompareEqual toNot Equal toBool ANDBool XORBool OR

Symbol

(expression)Function name (parameter list)EXPT-NOT*/MOD+-<,>,<=,>==<>ANDXOROR

Binding strength

Strongest binding

Weakest binding

26.07.200781

ST Structured text: Overview about Instructions

Instruction

Assignment :=

Callin a function block

RETURN

IF

CASE

FOR

WHILE

REPEAT

EXIT

Empty instruction

Example

PosWert := 10;

Ton1(IN:=Start, PT:=T2s); Output:= Ton1.Q

RETURN;

See the following pages

;

26.07.200782

IF Instruction

Is needed to branch in a program depending on conditions.

With the IF instructions it´s not possible to jump back in the PLC cycle.

„GOTO“ is not available

Keywords:

IF THEN

ELSIF

ELSE

END_IF

e.g.:

26.07.200783

IF Instruction (1)

Instruction block

Condition

Yes

No

IF Condition THENInstruction block;

END_IF

26.07.200784

IF Instruction (2)

IF a>b THENInstruction block A;

ELSEInstruction block B;

END_IF Instruction block A

Condition

Yes

No

Instruction block B

26.07.200785

IF Instruction (3)

IF Condition1 THENInstruction block A;

ELSEIF Condition2 THEN

Instruction block B;ELSE

IF Condition3 THENInstruction block C;

ELSEInstruction block D;

END_IFEND_IF

END_IF

Instruction block A

Condition 1

YesNo

Instruction block B

Condition 2

YesNo

Condition 3

YesNo

Instruction block C Instruction block D

26.07.200786

IF Instruction (4)

IF Condition1 THENInstruction block A;

ELSIF Condition2 THENInstruction block B;

ELSIF Condition3 THENInstruction block C;

ELSEInstruction block D;

END_IF

Instruction block A

Condition 1

YesNo

Instruction block B

Condition 2

YesNo

Condition 3

YesNo

Instruction block C Instruction block D

26.07.200787

IF Instruction (5)

IF bVar THEN.

IF a>b THEN.

IF LEFT(STR:= strVar, SIZE:=7) = 'TwinCAT' THEN.

IF Ton1.Q THEN.

IF Ton1(IN:=bVar, PT:=T#1s ) THEN

Conditions :

•BOOLEAN Variable

•Comparison

•Function calls

•Call FB Instances

•NO FB call!

What can the „BOOLEAN EXPRESSION“ be ?

26.07.200788

CASE Instruction

CASE Selection criterion OF

1: Instruction 1

2,4,6: Instruction 2

7..10 : Instruction 3

..

ELSE Default Instructions

END_CASE;

Two same values mustn´t be

available at the listing.

Instruction 1

Selection criterion = 1

Yes

No

Instruction 2

Selection criterion = 2Or 4 or 6

Yes

No

Yes

No

Instruction 3 Default Instructions

Selection criterion = 7Or 8 or 9 or 10?

26.07.200789

CASE Instruction Integer Selector Value with Enum types

Enum Typ:

TYPE Schritte :

( INIT:=0, START, AUTOMATIK, ENDE);

END_TYPE

CASE State OF

INIT: instructions; (*State=0*)

START: instructions; (*State=1*)

AUTOMATIK: instructions; (*State=2*)

ENDE: instructions; (*State=3*)

END_CASE

If the integer selector variable state is declared as enum, the value of the variable is visible in

the online mode.

VAR

State:Schritte;

(* State:INT also possible*)

END_VAR

26.07.200790

CASE Instruction Integer Selector Value with constants

CASE State OF

Step1: instructions; (*State=0*)

Step2: instructions; (*State=1*)

Step3..Step4: instructions; (*State=2 oder 3*)

END_CASE

VAR CONSTANT

Step1 : INT:= 0;

Step2 : INT:= 1;

Step3 : INT:= 2;

Step4 : INT:= 3;

END_VAR

VAR

State:INT;

END_VAR

26.07.200791

CASE Instruction proposal for a Statemachine

TYPE Steps :

( INIT:=0, START, AUTOMATIC, END);

END_TYPE

CASE State OF

INIT: Q0:=TRUE;

IF Transition THEN state := START ; END_IF

START: Q1:=TRUE ;

IF Transition THEN state := AUTOMATIC; END_IF

AUTOMATIC: Q2:=TRUE ;

IF Transition THEN state := END ; END_IF

END: Q3:=TRUE;

IF Transition THEN state := INIT ; END_IF

END_CASE

Instruction for the step

(Actions)

Instruction for the step

(Actions)

„step enabling condition“

(Transition)

„step enabling condition“

(Transition)

StepStep

26.07.200792

Repeat Instructions

The process flow requires the multiple handling of exactly the same program sequences, whose quantitiy is known at the run time.

Disadvantage of loops:During faulty programming, many repetitions take place infinitely.

If a continuous loop is executed this does not impair the start of the time slice (real-time). Tasks that will have a higher priority are still executed on time. Tasks that will have a lower priority are not longer executed.

1ms 2ms 3ms 4ms 5mse.g.:

1 2 3 41 1‘‘ 1‘1‘ 1‘‘‘

Forced switch toWin NT

Begin of a new time slice

26.07.200793

Loops (Overview)

Expression Work flow n cycle fix

FOR SINT/ INT /DINT

Pre repel Yes

WHILE BOOL Pre repel No

REPEAT BOOL Post repel No

All loops can be ended with the EXIT instruction, re gardless of the break-off condition.

26.07.200794

FOR loop

FOR i:=1 TO 12 BY 2 DO

Field[i]:=i*2; (*instruction*)

END_FOR

cycle nAt the beginning of the loop, the variable i is defined as start value (see example).The variable in incremented or decremented in each cycle depending on the step width (value after the keyword BY)

If i exceeds the end value (afterTO), the loop is not longer processed.

Start i:=Start value

Instruction block

cycle n

i>End value

Yes

No

I:= i+ Step width

26.07.200795

WHILE loop

i:=0;WHILE i<100 DO

Field[i]:=i*2; (*instruction*)i:=i+1;

END_WHILE

Boolean Expression

Instruction blockI:= i+ Step width

cycle n

cycle n

The instruction block of a WHILE loop is executed as long as the boolean expression supplies TRUE .The exit condition contains variableswhich can be changed in the instruction block.If the boolean expression is FALSE at the beginning, the instruction block of the WHILE loop is not processed .

Yes No

26.07.200796

REPEAT loop

i:=0;

REPEATField[i]:=i*2; (*Instruction*)i:=i+1;

UNTIL i>100

END_REPEAT

The instruction block of a REPEATloop is processed as long as (UNTIL) the boolean expression is no longer fullfilled.

The instruction block is executed at least once.

Booleanexpression

Instruction blockI:= i+ Step width

cycle n

Cycle n

Yes No

26.07.200797

FB calls in ST

TON1 (IN:= NOT TON1.Q , PT:=T#1s );

Q0:= TON1.Q

VAR

TON1:TON;

END_VAR

TON1(IN:= NOT TON1.Q, PT:=T#1s , Q=>Q0 );

from TwinCAT 2.8 :

26.07.200798

FB calls in ST explanation:

Create instance of FB

TON1 (IN:= NOT TON1.Q , PT:=T#1s );

VAR

TON1:TON;

END_VAR

Q0:= TON1.Q

Call with instance name

input parameters

Scan output

Q0:=TON1(IN:= NOT TON1.Q, PT:=T#1s);

Not possible: FB can have several outputs:

26.07.200799

FB calls in ST (alternative)

TON1.IN:= NOT TON1.Q ,

TON1. PT:=T#1s;

TON1();

Q0:= TON1.Q

VAR

TON1:TON;

END_VAR

26.07.2007100

FB calls in ST (alternative) explanation

TON1.IN:= NOT TON1.Q ;

TON1. PT:=T#1s;

TON1();

Q0:= TON1.Q;

VAR

TON1:TON;

END_VAR

Declaration

TRANSFER ONLY INPUT PARAMETER .

This is NO FB CALL!!!!!

scan output

FB CALL

26.07.2007101

FC calls in ST

Result:=Scale (x:=input, xug:=0.0, xog:=32767.0, yug :=0.0,yog:=100.0);

(* equal:*)Result:=Scale (input, 0.0, 32767.0, 0.0, 100.0);

(* equal :*)Result:=Scale (

x:= input,

xug:= 0.0,

xog:= 32767.0,

yug:= 0.0,

yog:= 100.0

);

26.07.2007102

FC calls in ST explanation:

Result := Scale (x:=input, xug:=0.0, xog:=32767.0, y ug:=0.0,yog:=100.0);

(* equal:*)

Result:=Scale (

x:= input,

xug:= 0.0,

xog:= 32767.0,

yug:= 0.0,

yog:= 100.0

);

Result CALL Input parameters

26.07.2007103

Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text

Part 3Sequential Function Chart

Step diagnosis

Appendix


Checker functions


26.07.2007104

SFC Sequential Function Chart

• Only one step is active at a time• The condition to change from one step to another is the transition.• In the action must be programmed what should be executed during the active step.

Step

Transition

ActionN

Qualifier

Following step

Transition

ActionN

Qualifier

Action,

Can be written in Structured Text, Instruction list, Ladder Diagram, Function Block Diagram and in

Sequential Function Chart .

26.07.2007105

Steps

• The activity of a step can be requested with Stepname.X.

• The duration of the activity of a step can be requested with Stepname.T .

• Both are components of a structure, which are created automatically from PLC Control. At the programming only the stepname has to be defined.

• Stepname.X and Stepname.T are local variable and can only beread.

Init

Transition

ActionN

„Normal“ Step“

Step1

Transition

ActionN

Initial stepactive at the

start

26.07.2007106

Actions

Step1

Transition

bOutputN

Action,can be a variable of type BOOL.

The variable is TRUE by activating the the step and FALSE

by leaving the step.

Transition

Step1

Transition

ActionN

Action, can be programmed in

-> Structured Text,

-> Instruction List,

-> Ladder Diagram,

-> Function block diagram, CFC/FBD

-> Sequential Function Chart

Transition

26.07.2007107

Actions, several allowed per step

Step1

Transition

STActionP

bOutputN

LDActionN

FBDActionR

26.07.2007108

Steps /alternative branches

• Only one branch can be active.

• Because only the left or the right branch is important, two transitions are necessary before the combination.

Stepa

Init

Transition

ActionN

Transition

ActionN

Transition

Transition

ActionNStepb

26.07.2007109

Steps / alternative branches

• The branches needn´t be symmetrical.

Stepa

Init

Transition

ActionN

Transition

ActionN

Transition

Transition

ActionN

Stepb

Transition

ActionN

Stepc

26.07.2007110

Steps /alternative branches

• Branches can be skipped.

Stepa

Init

Transition

ActionN

Transition

ActionN Transition

26.07.2007111

Steps /simultaneous branches

•Two branches are processed “simultaneous”.

Step_a

Init

Transition

ActionN

Transition

ActionN ActionNStep_b

Transition at the beginning of the

simultaneous branch

Transition at the „end“

Double line, symbolises the simultaneous

branch

26.07.2007112

Steps /simultaneous branches

• Simultaneous branches needn´t be symmetrical.

Step_a

Transition

Transition

ActionN

ActionN

Step_c

ActionN

Step_b

Transition

26.07.2007113

Transitions

A Transition must be of type „BOOL“. Possibilities:

• BOOLEAN Variable

• ST Instruction

• „programmed“ Transition

Init

bVariable

ActionN

BOOLEANVARIABLE

Step1

A > B

ActionN

ST instruction.

The result be must be of type BOOL.

Note: If the instruction is too long, the display will be shorten automatically.

26.07.2007114

Hides behind

Possible: FBD, LD, IL, ST.

Limitations: one network, one Instruction

sequence, no FB calls.

Transitions

Programmed Transitions

InitActionN

Step1ActionN

GTANDA

B

INPUT0

001Comment

A > B

Points to programmed

transition

„NOTHING CONNECT“

The result must be of type BOOL and is the transition

With this mark it´s only a

comment.

26.07.2007115

Final Scan

If a step is left, the processing takes exactly one more cycle. This behaviour can be used for “cleaning”in the action. E xample: Reset outputs.

ANDrelease

Step1.X

001

At the last pass the step.X = FALSE. Thus the variable

„Output “ is FALSE .

Step1

Go on

ActionN

Following step

Transition

ActionN Output

Step.X

Action processingt

t

1

0

1

0

1 Cycle

26.07.2007116

Final Scan

At a certain action the final scan leads to an unwa nted behaviour.

Step1

TRUE

ActionN

Behaviour:

Counter := Counter +1;

(*Counter increases at 2*)

Step.X

Action processingt

t

1

0

1

0

1 cycle1 cycle

Remedy: The step flag is only for one cycle 1:

IF Schritt.X THEN

Counter := Counter +1;

END_IF

(*Counter increases at 1*)

26.07.2007117

Qualifier

Controls the action processing after activating a s tep.

N: Non StoredStep

TRUE

ActionN Step.X

Action processingt

t

1

0

1

0

1 cycle

N: Non Stored

Combination in FBD

Step.X

001

Action processing

26.07.2007118

Qualifier

Controls the action processing after activating a s tep

S: SETStep

TRUE

ActionS

Combination in FBD

Step.X

Action processingt

t

1

0

1

0

1 cycle

Step.X

001

Action processing

SRS

R

26.07.2007119

Qualifier


R: RESETStep

TRUE

AktionR

Combination in FBD

Step.X

001

Action processing

SRS

R

Step.X

Action processingt

t

1

0

1

0

26.07.2007120

Qualifier


D: DELAY

Combination in FBD

Step.X

Action processingt

t

1

0

1

0

Delay

Step

TRUE

ActionD T#1s

Step.X

001

Action processingTON

IN

PT ET

Q

T#1s

26.07.2007121

Qualifier


L: LIMITEDStep

TRUE

Action

Combination in FBD

Step.X

Action processingt

t

1

0

1

0

LIMITED

L T#1s

Step.X

Action processingt

t

1

0

1

0

Limit

Step.X

001Action processing

TONIN

PT ET

Q

T#1s

AND

26.07.2007122

Qualifier


P: PULSEStep

TRUE

Action

Combination in FBD

P Step.X

Action processingt

t

1

0

1

01 cycle 1 cycle

Step.X

001

Action processing

R_TRIG

Clk Q

ATTENTION: A SECOND FLOW PROCESSES!

26.07.2007123

Qualifier, Combinations

SD: Stored and delayed

DS: Delayed and stored

SL: Stored and time limeted

26.07.2007124

Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text


Step diagnosis

Appendix


Checker functions


26.07.2007125

Sequential Function Chart step diagnosis

VAR

SFCEnableLimit: BOOL;

(*When it has the value TRUE, the timeouts of the s teps will be registered in SFCError. Other timeouts will be ignored.*)

SFCInit: BOOL;

(*When this boolean variable has the value TRUE the sequential function chart is set back to the Init step. The other SFC flags are reset too (i nitialization).

The Init step remains active, but is not executed, for as long as the variable has the value TRUE. It is only when SFCInit is again set to FALSE that the block can be processed normally. *)

26.07.2007126


SFCReset: BOOL;

(*This variable, of type BOOL, behaves similarly to SFCInit. Unlike the latter, however, further processing takes place after the initializa tion of the Init step. Thus for example the SFCReset flag could be re-set to FALSE in the I nit step.*)

26.07.2007127


SFCQuitError: BOOL;

(*Execution of the SFC diagram is stopped for as long as this boolean variable has the value TRUE whereby a possible timeout in the variable SFCError is reset.

All previous times in the active steps are reset wh en the variable again assumes the value FALSE.*)

SFCPause: BOOL;

(*Execution of the SFC diagram is stopped for as long as this boolean variable has the value TRUE.*)

SFCTrans: BOOL;

(*This boolean variable takes on the value TRUE whe n a transition is actuated. .*)

26.07.2007128


SFCError: BOOL;

(*This Boolean variable is TRUE when a timeout has occurred in a SFC diagram. If another timeout occurs in a program after the first one, it will not be registered unless the variable SFCError is reset first. *)

SFCErrorStep: STRING;

(*This variable is of the type STRING. If SFCError registers a timeout, in this variable is stored the name of the step which has caused the ti meout. *)

SFCErrorPOU: STRING;

(*This variable of the type STRING contains the nam e of the block in which a timeout has occurred. *)

26.07.2007129


SFCCurrentStep: : STRING;

(*This variable is of the type STRING. The name of the step is stored in this variable which is active, independently of the time monitori ng. In the case of simultaneous sequences the step is stored in the branch on the o uter right.No further timeout will be registered if a timeout occurs and the variable SFCError is not reset again.*)

26.07.2007130

Sequential Function Chart step diagnosis (from 2.8)

SFCErrorAnalyzation: STRING;

(*This variable, of type STRING, provides the trans ition expression as well as every variable in an assembled expression which gives a F ALSE result for the transition and thus produces a timeout in the preceding step. A re quirement for this is declaration of the SFCError flag, which registers the timeout. SFC ErrorAnalyzation refers back to a function called AppedErrorString in the TcSystem.Li b library. The output string separates multiple components with the symbol “|”. * )

SFCTip: BOOL;

SFCTipMode: BOOL;

(*This variables of type BOOL allow inching mode of the SFC. When this is switched on by SFCTipMode=TRUE, it is only possible to skip to the next step if SFCTip is set to TRUE. As long as SFCTipMode is set to FALSE, it is possible to skip even over transitions.*)

END_VAR

26.07.2007131

Sequential Function Chart process diagnosis

Implicit variable

26.07.2007132

• set step attributes for the step to be observed

Sequential Function Chart process diagnosis

26.07.2007133

Online (and per ADS) can be requested

26.07.2007134

Sequential Function Chart Tipmode

• insert implicit variable:

• effect:SFCTipSFCTipMode Transition

FALSETRUE TRUE

effect

Process stays in the current step

TRUETRUE TRUE Change to next step

TRUETRUE FALSE Change to next step

TRUEFALSE FALSE Process stays in the current step

FALSEFALSE TRUE Change to next step

26.07.2007135

Actions also in other IEC languages possible! (POU type : PRG, FB)

Action step2

Action step1

„Mainprogram“

26.07.2007136

Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text


Step diagnosis

Appendix


Checker functions


26.07.2007137

Remanent Flags Variables Attributes

These variables maintain their value, even after a power failure. When theprogram is run again, the stored values will be pro cessed further. A practical example would be an operations timer that recommences

timing after a power failure. A practical example wo uld be an operations timer that recommences timing after a power failure. All other variables

are newly initialized, either with their initialize d values or with the standard initializations.

TwinCAT supports two kind of remanent flags:

RETAIN PERSISTENT

26.07.2007138

Retain Persistent

Reset allRebuild all, ResetTo delete

To store

unlocated, located (%M)

Retain

Unlocated, located (%I, %Q, %M)Possible for

Persistent

26.07.2007139

Boot project

Requirement :

It should be possible to automate the loading and

the starting of the PLC project after switching on

the computer.

The PLC can start independent from the

user log on!

Power ON

Start NT

Start TwinCAT

Loading the boot project into the Run-Time

Start PLC

1

2

3

4

Log on

26.07.2007140

1&2

TwinCAT Auto boot Auto logon with Win NT

1

2

26.07.2007141

Create a boot project

Requirement:

1. The machine should work properly.

2. The hardware, software and the mappings are correct.

3. The PLC Control in the status online.

26.07.2007142

3&4

Enabling for loading the boot project for the run time system 1.

Number of run time systems

Enabling for loading and saving the RETAIN data for the run

time 1.

26.07.2007143

Sourcecode download

1.Goto Project/Options and press

the left mouse button.

2.A Window will open

3.Choose the Point Sourcedownload

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Timing for Sourcecode download

1.Implicit at load

Every time when you open the PLC Project the Sourcecode will be written down to the controller.

2.Notice at load

If the PLC Project changed, you get a message box, when you open the project.

3.Implicit at create boot project.

Everytime you create a bootproject, the sourcecode will be transfered to the controller

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Timing/Extent for Sourcecode download

1.On demand

The Sourcecode will be written down to the controller on demand.

Online/Sourcecode download

Extent

Sourcecode only

•The plc project will be written in the controller

All files

•The plc project with all libaries will be written tin the controller

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Plc project open from the controller

1. You can open the actuell plc projekt direct from the controller

2. Under File/Open you can open the project direct from the plc.

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Were retain and persitent data loaded successfully?

The structure component shows if the

persistent/retain data were loaded successfully.

In order to be able to view this data structure, the "PlcSystem.lib"

library must be linked in.

(Global variable)

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Meaning of the flags

Reserved7

Reserved6

PERSISTENT variables: INVALID (the back-up copy was loaded, since no valid data was present)

5

PERSISTENT variables: LOADED (without error)4

Reserved3

RETAIN variables: REQUESTED (RETAIN variables should be loaded, a setting in TwinCAT System Control)2

RETAIN variables: INVALID (the back-up copy was loaded, since no valid data was present)

1

RETAIN variables: LOADED (without error)0

DescriptionBit number

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How can an access to the bootdata flags take place?

Because the variable exists in the PLC, (implicit) it can be prompted directly.

TcPlcSystem.Lib

IF GETBIT32(inVal32:= SystemInfo.BootDataFlags , bitNo:=4) THEN

errLoadBootData:=FALSE;

strBootDataState:= 'PersistentData OK';

ELSIF GETBIT32(inVal32:= SystemInfo.BootDataFlags , bitNo:=5) THEN

errLoadBootData:=TRUE;

strBootDataState:= 'Error Load PersistentData ';

END_IF

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Write Persistent Data on demand

With the fuction block„WritePersistentData“

(TcPlcUtilities.Lib) it is possible to initiate the writing of the Persistent

Data.

The writing takes place at the Shut Down of the PLC (standard).

While the function block is busy, the access to the Persistent Variable is

not allowed!

TcPlcUtilities.Lib

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Write Persitent Data on demand, Example:

IF ReqWritePersistent THEN

fbWritePersistent(NETID:='' , PORT:=801 , START:=TR UE , TMOUT:=T#500ms );IF fbWritePersistent.ERR THEN

fbWritePersistent(START:=FALSE );ReqWritePersistent:=FALSE;

ELSIF NOT fbWritePersistent.BUSY THEN

fbWritePersistent(START:=FALSE );ReqWritePersistent :=FALSE;

END_IFEND_IF

PLC Runtime

Further start after edge

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Internal Libraries

Create and test project

Delete unnecessary elements of a library

Unnecessary elements:All tasks will be deleted in the task

configuration.

All POUs, which are not to belong to thecontents of a library, are

removed.

All global variables will be deleted.

Valid: global constants, self defined data types.

Save as internal *.Lib

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Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text


Step diagnosis

Appendix


Checker functions


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CheckDivByte

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CheckDivWord

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CheckDivDWord

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CheckDivReal

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CheckRangeSigned

Variable to be checked

Checker function

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CheckRangeUnsigned

Variable to be checked

Checker function

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CheckRangexxx can be done with TYPES

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Overview

Contents

Part 1


Software model

Identifier


Variables classes

Block types


Timing

Part 2


Variables II Arrays

Checkbounds

Structured text


Step diagnosis

Appendix


Checker functions


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Paint station (PRG)

Motor Encoder

Start

Stop

nozzle 1-3

workpiece

Part exercise:

� Switch on and off the plant

� simulate encoder

� Request marks & switch on the nozzles

� Safe state when plant off.

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Creating the variables list

Identifier %I %Q Initialvalue

Type

bStart AT%IX0.0 False BOOL Global

bStop AT%IX0.1 False BOOL Global

bMotor AT %QX0.0 False BOOL Global

bDuese_1 AT %QX0.1 False BOOL Global



Marke_1 400 WORD Local



Marke_End 1600 WORD Local

Inc 0 WORD Local

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Switch on / off the plant

The switches bStart and bStop should be used as pus h-button.

To safe the status, it´s necessary to add a hold el ement (RS). There are two bistable memorys under the standard function blocks .

The dominant input is marked with xxx1.

Set

Reset1

Q1

Set1

Reset

Q1

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Simulate encoder & check bounds

The encoder value is incremented each cycle around 1.This is implemented with the operator ADD. Thus a running encoder develop.

LD IncADD 1ST Inc

LD INCGT Marke_1AND (INCLT Marke_2)ST bDuese_1(

It is checked, if the encoder value stands between Marke_1 und Marke_2 .

Marke_1 GT Inc LT Marke_2

In this case, the Duese_1 is switched ST

IL

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Safe state when plant off

If the plant is switched off, all nozzles and the conveyer should be stopped.

If the conveyor is stopped, the encoder should became the value 0.

LD FALSE

ST bDuese_1

ST bDuese_2

ST bDuese_3

ST bMotor

LD 0

ST Inc

Load example

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System Manager

By adding a correct project (i.e. the project has been compiled in TwinCAT PLC Control without errors, and afterwards stored), the PLC configuration will be integrated into the current system configuration. The address located I/O variables will be read.

By selecting the added PLC project in the tree, the appropriate dialog IEC61131-3 appears on the right side.

At I/O configuration, you can configure the fieldbus cards (master) and the boxes (slave) for the given configuration.

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Master cards

Different fieldbus systems. Each fieldbus has sever al master cards from different manufacturers (Beckhoff FC, Siemens CP, Hilscher CIF). Several different fieldb us master cards can be used parallel.

The FC 310X supports thePROFIBUS protocols:

� PROFIBUS-DP (as Master, Slave and Multi-Slave),

� PROFIBUS-DPV1 (as Master)

� PROFIBUS-MC (as Master)

DP Master

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Slave modules

With the dialog “Insert I/O device” it´s possible t o insert the Beckhoff slave modules. If the Profibus Slave doesn´ t exist in the list it´s possible to select Generic Profibus Box and search the profibus box in the gse file.

Each GSE file which was read by TwinCAT, can bee seen in the list ( with the name of the producer).

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Modular Structure of the Slaves modules

Beckhoff DP-Slave General DP-Slave

x N

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Paint station (PRG)

contact coil

Cursor in KOP is used for inserting

new elementsLoad example Graphical elements in LD

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context menue

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Insert new elements

Identifier

The following elements can be inserted at the marke d cursor positions

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Paint station (PRG)

Load exampleGraphical elementesin FBD

Operator

Cursor in FBD is used for inserting new elements

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Context menue

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Insert new elements

Dependent by the the cursor position

the following language elements

can be inserted.

The program can be expand to the left and the right side.

List of the operators (AND, OR, GE, ADD, ..) implemented by the system.

Documents

TwinCAT IEC61131-3