Automation Direct | LKD-DEV-M | Owner's manual | Lookout Direct Developer’s Manual

Lookout

™

Direct

Developer’s Manual

License Agreement

“Valued Technology”

This License Agreement is your proof of license. Please treat it as valuable property.This is a legal agreement between you (either an individual or entity) the end-user of this product, and Automation Direct. If you do not agree to the terms of this Agreement, promptly return the package and any accompanying items to Automation Direct for a full refund.

LookoutDirect SOFTWARE LICENSE

1. GRANT OF LICENSE — This LookoutDirect License Agreement (“License”) permits you to use one copy of the specified version of the LookoutDirect software product (“Software”) on any single computer, provided the Software is in use on only one computer at any time. If you have multiple Licenses for the Software, then at any time you may have as many copies of the Software in use as you have Licenses. The Software is deemed “in use” on a computer when it is loaded into the temporary memory (i.e. RAM) or installed into the permanent memory (i.e. hard disk, CD--ROM or other storage device) of that computer, except that a copy may be installed on a network server for the sole purpose of distribution to other computers that are not currently “in use”. If the anticipated number of Software users will exceed the number of applicable Licenses, then you must have a reasonable mechanismor process in place to assure that the number of persons using the Software concurrently does not exceed the number of Licenses. If the Software is permanently installed on the hard disk or other storage device of a computer (other than a network server) and oneperson uses that computer more than80%of the timeit is in use, then that person may also use the software on a single portable computer or a single computer at home.

2.

COPYRIGHT —The Software is owned by Automation Direct or its suppliers and is protected by United States copyright laws and international treaty provisions. Therefore, you must treat the Software like any other copyrighted material (e.g., a book or musical recording) except that you may: a. Make one backup copy of the Software solely for backup or archival purposes.

b. Transfer the Software to a single hard disk provided you keep the original and the backup solely for archival purposes. You may not copy any written materials that may accompany the Software.

3. OTHER RESTRICTIONS—This LookoutDirect License Agreement is your proof of license toexercise therights grantedherein andmust beretained by you. You may not rent or lease the Software, but you may transfer your rights under this

LookoutDirect License Agreement on a permanent basis provided that you transfer this License Agreement, the Software, and all accompanying written materials and retain no copies. The recipient must also agree to unequivocally abide by the terms contained in this License Agreement. You may not reverse engineer, decompile, or disassemble the Software. Any transfer of the Software must include the most recent update and all prior versions. If the Software is acquired within the United States, you may not export the Software outside of the United States without first complying with all applicable USexport laws and regulations. You acknowledge that the Software will not function without a certain hardware key. This hardware key will be furnished to you by Automation Direct and you agree that such hardware key is to be used solely with the Software provided.

DISTRIBUTION LIMITATIONS

If you have acquired the development/runtime package, you may distribute process files created with the Software, provided that:

1.

each recipient of your process file has a valid license for a separate runtime copy of the Software;

2.

you include the following copyright notice, either on--screen in your process file’s About Box or written documentation, with each distributed copy of your

3.

process file: “Copyright E [year] Automation Direct by Koyo, Inc. (Based on materials of National Instruments Corporation).

All Rights Reserved”;

4.

you do not use Automation Direct’s or National Instruments’ (”NI”) names, logos, or trademarks to market your process file without written permission; and

5.

you agree to indemnify, hold harmless, and defend Automation Direct and NI (including their officers, directors, employees, and agents) and their suppliers fromand against any claims.

LIMITED WARRANTY

1. Automation Direct warrants the Software will perform substantially in accordance with the written materials for a period of ninety (90) days from the date of receipt.

2. Automation Direct warrants that any hardware accompanying the Software will be free fromdefects in materials and workmanshipunder normal use andservice for a period of one (1) year from the date of receipt.

NO OTHER WARRANTIES.

EXCEPT AS EXPRESSLY SET FORTHABOVE, THE SOFTWARE IS PROVIDED“AS IS”

WITHOUT WARRANTYOF ANYKIND, AND NO OTHER WARRANTIES, EITHER EXPRESSED OR IMPLIED ARE

MADE WITH RESPECT TO THE SOFTWARE, INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTIES OF

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THE RESULTS OF THE USE OF THE SOFTWARE IN TERMS OF CORRECTNESS, ACCURACY, RELIABILITY, OR

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Customer Remedies —Automation Direct’s entire liability and your exclusive remedy shall be at Automation Direct’s option.

Automation Direct will either refund the price paid, or repair or replace the Software or hardware that does not meet Automation

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OR HARDWARE. THIS LIMITED WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS. YOU MAY HAVE OTHERS,

WHICH VARY FROM STATE TO STATE.

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The Software and documentation are provided with RESTRICTED RIGHTS. Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at

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30040 (under license from National Instruments Corporation, 11500 N. Mopac Expressway, Austin, Texas 78759--3504).

This agreement is governed by the laws of the State of Georgia.

WARNING

(1) THE SOFTWARE IS NOT DESIGNED WITH COMPONENTS AND TESTING FOR A LEVEL OF RELIABILITY

SUITABLE FOR USE IN OR INCONNECTION WITH SURGICAL IMPLANTS OR AS CRITICAL COMPONENTS IN

ANY LIFE SUPPORT SYSTEMS WHOSE FAILURE TO PERFORM CAN REASONABLY BE EXPECTED TO CAUSE

SIGNIFICANT INJURY TO A HUMAN.

(2) IN ANY APPLICATION, INCLUDING THE ABOVE, RELIABILITY OF OPERATION OF THE SOFTWARE CAN BE

IMPAIRED BY ADVERSE FACTORS, INCLUDING BUT NOT LIMITED TO FLUCTUATIONS IN ELECTRICAL

POWER SUPPLY, COMPUTER HARDWARE MALFUNCTIONS, COMPUTEROPERATINGSYSTEMSOFTWARE

FITNESS, FITNESS OF COMPILERS ANDDEVELOPMENT SOFTWARE USED TO DEVELOP AN APPLICATION,

INSTALLATION ERRORS, SOFTWARE AND HARDWARE COMPATIBILITY PROBLEMS, MALFUNCTIONS OR

FAILURES OF ELECTRONIC MONITORING OR CONTROL DEVICES, TRANSIENT FAILURES OF ELECTRONIC

SYSTEMS (HARDWARE AND/OR SOFTWARE), UNANTICIPATED USES OR MISUSES, OR ERRORS ON THE PART

OF THE USER OR APPLICATIONS DESIGNER (ADVERSE FACTORS SUCH AS THESE ARE HEREAFTER

COLLECTIVELY TERMED ”SYSTEM FAILURES”). ANY APPLICATION WHERE A SYSTEM FAILURE WOULD

CREATE A RISK OF HARM TO PROPERTY OR PERSONS (INCLUDING THE RISK OF BODILY INJURY AND

DEATH) SHOULD NOT BE RELIANT SOLELY UPON ONE FORM OF ELECTRONIC SYSTEM DUE TO THE RISK

OF SYSTEM FAILURE. TO AVOID DAMAGE, INJURY, OR DEATH, THE USER OR APPLICATION DESIGNER MUST

TAKE REASONABLY PRUDENT STEPS TO PROTECT AGAINST SYSTEM FAILURES, INCLUDING BUT NOT

LIMITED TO BACK--UP OR SHUT DOWN MECHANISMS. BECAUSE EACH END--USER SYSTEM IS

CUSTOMIZED AND DIFFERS FROM UTILIZED TESTING PLATFORMS AND BECAUSE A USER OR

APPLICATION DESIGNER MAY USE THE SOFTWARE IN COMBINATION WITH OTHER PRODUCTS IN A

MANNER NOT EVALUATED OR CONTEMPLATED BY PLCDIRECT OR ITS SUPPLIERS, THE USER OR

APPLICATION DESIGNER IS ULTIMATELY RESPONSIBLE FOR VERIFYING AND VALIDATING THE

SUITABILITY OF THE SOFTWARE WHENEVER THE SOFTWARE IS INCORPORATED IN A SYSTEM OR

APPLICATION, INCLUDING, WITHOUT LIMITATION, THE APPROPRIATE DESIGN, PROCESS AND SAFETY

LEVEL OF SUCH SYSTEM OR APPLICATION.

Lookout is a registered trademark of National Instruments Corporation.

Lookout

TM

Direct

Developer’s Manual

Please include the Manual Name and the Manual Issue, both shown below, when communicating with Technical Support regarding this publication.

Manual Name: LookoutDirect Developer’s Manual

Issue: First Edition, Rev. A

Issue Date: 11/02

Issue

First Edition

Rev. A

Date

8/01

11/02

Publication History

Description of Changes

Orginal

Deleted Chapter 11 and updated index

Contents

About This Manual

How to Use This Manual Set .........................................................................................vii

Document Conventions..................................................................................................vii

Technical Support ..........................................................................................................viii

Phone ...............................................................................................................viii

World Wide Web.............................................................................................viii

Chapter 1

Expressions

Creating Expressions .....................................................................................................1-3

Data Polymorphism .........................................................................................1-3

Path Names in LookoutDirect .........................................................................1-6

Expressions on Control Panels ........................................................................1-8

Expression Objects ..........................................................................................1-10

Expressions as Parameters...............................................................................1-11

Expressions as Connections ............................................................................1-12

Edit/Insert Expression Dialog Box ................................................................................1-12

Expression Syntax..........................................................................................................1-14

White Space.....................................................................................................1-14

Arithmetic Operators .......................................................................................1-15

Text Operator...................................................................................................1-15

Comparison Operators.....................................................................................1-15

Expression Functions .....................................................................................................1-18

Logical Functions ............................................................................................1-18

Lookup Functions ............................................................................................1-20

Mathematical Functions ..................................................................................1-21

Statistical Functions.........................................................................................1-24

Text Functions .................................................................................................1-26

Trigonometric Functions .................................................................................1-29

Date/Time Functions .......................................................................................1-31

Quality Functions ............................................................................................1-31

Chapter 2

Graphics

Setting Snap to Grid.......................................................................................................2-1

Static Graphics ...............................................................................................................2-2

Displaying Text, Plates, Insets, Rectangles, and Lines ..................................2-2

Displaying Static Custom Graphics.................................................................2-4

© Automationdirect.com

i Developer’s Manual

Contents

Dynamic Graphics..........................................................................................................2-6

Displaying Dynamic Logical Signals ..............................................................2-7

Displaying Dynamic Numeric Signals ............................................................2-10

Displaying Dynamic Text Signals ...................................................................2-12

Finding a Lost Graphics File..........................................................................................2-13

Creating Custom Graphics .............................................................................................2-14

Creating Custom Graphics Example ...............................................................2-14

Creating the Graphic .........................................................................2-14

...........................................................................................................2-16

Save or Export the Graphic and Place in LookoutDirect .................2-16

Testing the Graphic in LookoutDirect ..............................................2-16

Graphic File Types.........................................................................................................2-18

Bitmaps ............................................................................................................2-18

Metafiles ..........................................................................................................2-18

Bitmaps or Metafiles?......................................................................................2-18

Memory Considerations...................................................................................2-19

Chapter 3

Serial Port Communication Service

Introduction to Driver Objects .......................................................................................3-1

Understanding the Communication Service ..................................................................3-2

Defining Serial Port Settings..........................................................................................3-3

Selecting the Serial Port...................................................................................3-3

Setting Receive Gap ........................................................................................3-3

Selecting the Serial Connection.......................................................................3-4

Hardwired Settings ............................................................................3-4

RTS/CTS Handshaking Settings .......................................................3-4

Dial-Up Modem Settings ..................................................................3-5

Serial Port Hangup...........................................................................................3-7

Serial Port Diagnostics...................................................................................................3-7

Chapter 4

Networking

Registering Computers...................................................................................................4-2

Logging Data..................................................................................................................4-3

Time Synchronization......................................................................................4-3

Checking the Network Connection between Two Computers.......................................4-6

Chapter 5

Dynamic Data Exchange

Linking LookoutDirect to Other Applications...............................................................5-2

DDE Server Example ......................................................................................5-2

Developer’s Manual ii www.Automationdirect.com

Contents

DDE Client Example .......................................................................................5-3

DDE Peer-to-Peer Example.............................................................................5-4

DDE Alarms .................................................................................................................5-5

Chapter 6

Security

Logging On ....................................................................................................................6-2

User Manager.................................................................................................................6-4

Creating User Accounts...................................................................................6-5

Creating Groups...............................................................................................6-6

Modifying Users and Groups ..........................................................................6-7

Special Users and Groups................................................................................6-8

Control Security .............................................................................................................6-9

Viewing Security ...........................................................................................................6-10

Control Panels .................................................................................................6-10

Controllable Objects ........................................................................................6-10

System Security Settings .................................................................................6-11

Network Security ...........................................................................................................6-12

Configuring Security for Processes and Objects .............................................6-12

Permissions .......................................................................................6-12

Advanced Security ............................................................................6-15

Keeping Security Precedence Simple ............................................................................6-18

Process File Edit Security ..............................................................................................6-19

Action Verification ........................................................................................................6-20

Importing Old Security Files into LookoutDirect 4.......................................................6-21

Chapter 7

Logging Data and Events

Spreadsheet Logger........................................................................................................7-1

Data Location ..................................................................................................7-2

CSV Files.........................................................................................................7-3

File and Disk Errors.........................................................................................7-3

Concurrent File Access....................................................................................7-4

Information Overload ......................................................................................7-4

Citadel Historical Database ..........................................................................................7-5

Default Data Location .....................................................................................7-5

Process Data Location .....................................................................................7-6

Creating a Historical Database ........................................................................7-7

Logging Criteria ................................................................................7-9

Alarm Information Overload ...........................................................................7-9

Event Logger..................................................................................................................7-10

Event Data Location .......................................................................................7-10

Event Information Overload............................................................................7-10


iii Developer’s Manual

Contents

Report Generation ..........................................................................................................7-11

Control Panel Reports......................................................................................7-11

Third-Party Reports .........................................................................................7-13

Chapter 8

Structured Query Language

Introduction ....................................................................................................................8-1

What is ODBC? ...............................................................................................8-1

What is SQL?...................................................................................................8-1

Creating a Citadel ODBC Data Source..........................................................................8-2

Accessing Citadel Data ..................................................................................................8-5

Traces Table.....................................................................................................8-5

Points Table .....................................................................................................8-6

Data Transforms ..............................................................................................8-6

SQL Examples .................................................................................................8-7

Accessing Citadel Data with Microsoft Query ................................................8-8

Accessing Citadel Data with Microsoft Excel.................................................8-13

Accessing Citadel Data with Microsoft Access...............................................8-13

Accessing Citadel Data with Visual Basic ....................................................................8-17

Chapter 9

Alarms and Events

Defining Alarm Conditions............................................................................................9-1

Database-Generated Alarms ............................................................................9-1

Alarm Objects ..................................................................................................9-2

The Alarm Subsystem ....................................................................................................9-4

Selecting Processes to Monitor for Alarms .....................................................9-4

Alarm Areas.....................................................................................................9-4

Alarm Priorities ...............................................................................................9-6

Alarm Window ................................................................................................9-6

Alarm Display Options ....................................................................................9-7

Alarm Filters....................................................................................................9-8

Alarm Print ......................................................................................................9-10

Alarm Acknowledgment..................................................................................9-11

Acknowledging Alarms Programatically ........................................................9-13

Chapter 10

Redundancy

Standby Basics ...............................................................................................................10-2

Failover Scenarios ...........................................................................................10-3

Configuring Standby ......................................................................................................10-4

Enabling File Sharing in Windows 98/95 and Windows NT ..........................10-4

Developer’s Manual iv www.Automationdirect.com

Contents

Time Synchronization with Standby Computers.............................................10-5

Implementing Redundancy ............................................................................................10-6

Redundancy Overview ....................................................................................10-6

Setting up the Primary Process and Computer ................................................10-6

Setting up the Standby Process and Computer................................................10-9

Configuring Clients for Standby Operation ....................................................10-11

Chapter 11

Editing Object Databases

Editing Database Parameters .........................................................................................11-1

Numeric Member Parameters..........................................................................11-4

Logical Member Parameters............................................................................11-7

Text Member Parameters ................................................................................11-8

Importing and Exporting Object Databases...................................................................11-9

Exporting an Object Database .........................................................................11-9

Creating a Database Spreadsheet.....................................................................11-11

Importing an Object Database .........................................................................11-13

Copying an Object Database ..........................................................................11-15

Glossary

Appendix A

Networking With DDE

NetDDE Networking Considerations ............................................................................A-2

Multilink NetDDE Networking .....................................................................................A-3

Linking Controllable Objects ..........................................................................A-3

Linking Controllable Objects Together Across a Network ..............A-3

Linking Non-Controllable Objects .................................................................A-4

To Access Real-Time Data at Another Computer ............................A-4

Table Networking ..........................................................................................................A-6

Hardware Networking....................................................................................................A-10

Multilink and Table Networking Comparison ..............................................................A-11

Setting up Networking with DDE..................................................................................A-12

Running NETDDE.EXE Automatically..........................................................A-12

Windows 98/95 .................................................................................A-12

Windows NT .....................................................................................A-12

Adding a Trusted DDE Share..........................................................................A-13

Appendix B

CBL Compiler

CBL Compiler Error Messages......................................................................................B-2


v Developer’s Manual

Contents

Appendix C

Lookout.INI File

Index

Developer’s Manual vi www.Automationdirect.com

About This Manual

How to Use This Manual Set

The Getting Started guide contains installation instructions and a basic introduction to LookoutDirect features and functionality. It includes general information to help acquaint you with the important elements of

LookoutDirect along with tutorial exercises to introduce you to the basics of building a LookoutDirect process.

The Object Reference Manual is in Portable Document Format (PDF) and describes the LookoutDirect object set. It is available on the LookoutDirect

CD in the documentation

directory. The LookoutDirect installation gives you the option of copying the PDF files into the

LookoutDirect/documentation

folder on your hard drive. To view these files, you must have Adobe Acrobat Reader 3.0 or later installed.

If you do not have Adobe Acrobat Reader installed, you can install it from the

LookoutDirect/documentation

directory or from the Adobe web site at

www.adobe.com.

This Developer’s Manual explains how to create control processes for your

HMI/SCADA applications. This manual includes detailed explanations of various LookoutDirect features, functions, and services.

Document Conventions

The following document conventions are used in this manual.

»

Indicate the path for nested menu and command selections.

Example: Start » Programs » xxx

Indicates a tip that provides helpful information related to the current procedure or topic.

Indicates a important supplementary information pertinent to the current procedure or topic.

Denotes a caution statement. Failure to follow the guidance provide in the caution statement could result in a loss of data or an interruption to a critical process being controlled or monitored by LookoutDirect.


vii Developer’s Manual

Introduction

Technical Support

bold face text

italic

monospace

Denotes the name of dialog boxes, property sheet items, application features, and menu commands that you select as part of a procedure.

Denotes references to dialog boxes, property sheet items, application features, and menu commands that are not part of the current procedure, or key concepts.

Denotes characters that you enter from the keyboard, code/syntax examples. The monospace font is also used to express proper names of disk drives, paths, directories, programs, subprograms, subroutines, device names, functions, operations, variables, filenames and extensions.

Phone

Contact Automation Direct’s technical support department toll free at

1-770-844-4200. Technical support is available weekdays from 9:00 a.m through 6:00 p.m. EST.

World Wide Web

Visit the Automation Direct website at www.automationdirect.com and click on Technical Support to access a wide variety of technical support assets including print-on-demand documentation and software downloads.

Developer’s Manual viii www.Automationdirect.com

1

Expressions

This chapter explains the features and uses of LookoutDirect expressions, which can act as variables, capable of flexible, real-time math statements, condition testing, and other complex operations.

LookoutDirect expressions can use spreadsheet-style formulas with a mixture of constants and variable signals from objects. They can be short and simple, or extremely complicated with several signal inputs, function calls, and multiple levels of parentheses.

A single expression can incorporate any number of numeric, logical, and text signals within its calculation. However, the result of the expression can be only one of three types: numeric, logical, or text. The outermost function or operator in the expression returns a variable type that determines the overall signal type of the expression.

While an expression produces a single type of data, most LookoutDirect objects interpret data according to the data type that object needs for a particular data member. You can connect a logical output to a numeric input, and the arriving data will be interpreted as a 0 or a 1. Refer to the Data

Polymorphism section of this chapter for detailed information on how

LookoutDirect interprets data without respect to the original type.

Simple expressions consist of a single value. Simple expressions do not contain any modification, manipulation, math, or logic (for example, a single object with a name like

Pot1

). When you add any functionality to a simple expression, you create a complex expression (for example,

Pot1 > 33

).

The following examples are typical expressions. Depending on your system requirements, your expressions might be much more involved.

True

Always returns the value true (on).

Pot1

Returns the current value [the

(intrinsic)

data member] of Pot1.

879.03


1-1 Developer’s Manual

Chapter 1 Expressions

Developer’s Manual

Always returns the value 879.03.

1:04:33

Returns the value 0.0448264. If formatted in hours, minutes, and seconds, it is displayed as 1:04:33.

Pressure * 2.31

Multiplies Pressure by 2.31.

(Switch1 or Switch2) and TankLevel > 65.2

If Switch1 or Switch2 is true, and TankLevel is greater than 65.2, return true. Otherwise, return false.

Pressure >= Setpoint and !ReliefValve and TimeOccuring > 0:30

If Pressure is greater than or equal to Setpoint, and ReliefValve is false, and TimeOccuring is greater than 30 seconds, return true. Otherwise, return false.

if(PLC1.AutoPos, AutoTemp, if(PLC1.ManPos, ManualTemp,0))

If the alias member AutoPos of PLC1 is true, return the value of

AutoTemp. If the alias member ManPos of PLC1 is true, return the value of ManualTemp. Otherwise, return the value 0.

tif(HOA=1,“Hand”,tif(HOA=2,“Off”,“Auto”))

tif

is the text version of the if

function. If the HOA switch is at position

1, return

Hand

. If the HOA switch is at position 2, return

Off

. Otherwise, return

Auto

.

You can accomplish much the same thing with the following tchoose expression as you can with the previous tif

expression.

tchoose(HOA,"hand","Off","Auto")

If the HOA switch is at position 1, return

Hand


Off


Auto

.

Make sure that your expressions do not attempt to calculate illegal operations, such as dividing by zero or finding the arc cosine of a number greater than 1.

If a signal can assume a value that could cause LookoutDirect to attempt an illegal mathematical operation, you should specifically test for that condition in the expression. Expressions trap illegal mathematical operations and generate alarms in the Math alarm area. The alarms do not reset until you correct the expression. The following list includes some of the illegal conditions that LookoutDirect traps:

• attempting to divide by zero

1-2 www.Automationdirect.com


• taking the square root of a negative number

• numeric underflow

• numeric overflow

Note

If any value referenced in an expression changes when an event occurs, the expression automatically recalculates. This is the same event-driven concept that objects implement.

Creating Expressions

Because LookoutDirect uses expressions in many places, you can create expressions as independent objects, parameters in objects, connections to object data members, or you can insert expressions on control panels.

Through dialog boxes, you create expressions during process development.

There are three types of data entry fields in LookoutDirect dialog boxes—white, yellow, and green. White data entry fields accept only constant values, yellow data entry fields accept expressions, and green fields accept

URLs.

Data Polymorphism

LookoutDirect data is not strongly typed, which means that it does not need to be interpreted as the type it was originally cast in. Data polymorphism in

LookoutDirect means that data of one type is interpreted appropriately when connected to an input of another type. You can select the data type you want an expression to be displayed as in the Display Type field, shown in the following dialog box.




Data Type

Logical 0 or 1

The following table describes how data types are used by inputs of a different type.

Table 1-1. Data Type Conversion

Interpreted as Numeric

Interpreted as Text

ON or OFF —

Interpreted as Logical

Developer’s Manual 1-4 www.Automationdirect.com


Data Type

Numeric —

Table 1-1. Data Type Conversion (Continued)

Interpreted as Numeric

Interpreted as Text

digits of the number

Text Appear as digits if the string consists only of digits in a valid

LookoutDirect display format, such as a decimal number or a scientific expression.

In a time format, such as

10:05:30

, the text is interpreted as a number

(the fraction of one day represented by the time quantity) in scientific notation.

If the text string does not consist of digits in a valid LookoutDirect format, the text is interpreted as a 0, with the exception of

ON

or

TRUE

, which display as 1.

The text strings

OFF

or

FALSE

are interpreted as 0, by default.

—

Interpreted as Logical

0

displays as OFF

Any value other than

0 displays as ON

Interpreted as a 0 or as

OFF, except when the text string consists of a

1

,

On

, or

True

, all of which are interpreted as

ON.

By default, the text strings

0

,

Off

, or

False

are interpreted as OFF.

After you have placed an expression on your panel, you cannot change the data type in that expression. You have to delete that expression and place a new one if you want to change data types.

Expressions used as parameters in LookoutDirect objects do not permit you to select the data type because the object interprets input according to the data type required by that object. Making LookoutDirect data polymorphic permits you to use output of a data type different from that required by an object, as long as the output can be interpreted meaningfully by the object.

Polymorphic data types affect the DataTable object. In versions earlier than

LookoutDirect 4, the DataTable used data members such as

A1.logical

to set the type of data in a particular cell.




Note

The LookoutDirect 3.xx DataTable data members are preserved in LookoutDirect 4 for the sake of compatibility. It is not necessary to use the data-typed data members to simulate polymorphic data. To achieve this compatibility, however, LookoutDirect

DataTable data is still strongly typed. You must input numeric data to DataTable numeric data members, logical data to DataTable logical data members, and so on.

Path Names in Lookout

Direct

In versions of LookoutDirect prior to LookoutDirect 4, you could only have one process running in any instance of LookoutDirect, and there were no folders in a process to organize objects. Networking was done through DDE, which used specific paths. In LookoutDirect 4, the relationship between objects running in different processes on different computers is far more flexible and potentially complicated.

When you insert an expression on a LookoutDirect panel or make a connection to or between data members, you might be displaying a value that comes from the process containing that panel. You might also need to display a value that comes from another process running on the same computer or from a process running on some other computer in your network.

A path can be absolute, starting with a computer’s fully qualified network name and leading through nested directories and subdirectories to a single object; or relative, instructing the computer to search for an object in some directory defined not from the computer down, but relative to the currently active folder.

To provide maximum programming flexibility, you can use a number of different levels of relativity, or path relativity modes, in setting the path to the data when you create an expression. These modes operate very much like other relative paths used in DOS operations, spreadsheet cells, and Web page addressing.

You can set a path for each individual object or connection, using a different level of relativity. These path relativity modes include

• Relative (the LookoutDirect default)

• Process Relative

• Computer Relative

• Absolute

The level of path relativity you choose makes a difference in how your process operates when copied or moved to another computer. For instance, suppose you have a client process running on computer Alfred that refers to objects in a server process also running on computer Alfred. If you run that




client process on computer Bert, will it refer to objects on computer Alfred or computer Bert?

Setting the level of path relativity is how you can control which objects your processes refer to. The key point to remember about path relativity modes in

LookoutDirect is that the modes are distinguished by the path prefix.

In Relative mode, the form of the path is

object

or

folder\object

without prefix.

Relative mode is the default mode in LookoutDirect 4. All paths are relative to the folder or process that contains the expression you are creating or the object you are connecting to. Use Relative mode when you connect objects that should be grouped together and that should be copied or moved as a group.

Connections between objects in a folder should use Relative mode so that they can be copied and moved elsewhere while maintaining the same relationship with each other.

Process Relative mode is indicated by a single prefixed backslash (

\

) followed by a folder or object name, as in

\folder\...folder\object

or

\object

Use Process Relative mode when you want to make a connection between two objects in different folders in the same process.

Computer Relative mode is indicated by a prefix consisting of two backslashes, a period, and a backslash (

\\.\

) followed by a process name, as in

\\.\process\folder\...folder\object

Use Computer Relative mode when you want to reference other processes running on the same computer.

For instance, if you had a process called

Station_Control

that called a number of other processes by name on computer Alfred, you could use that



same

Station_Control

process on computer Bert to refer to the identically named processes running on computer Bert.

Absolute mode is indicated by two backslashes (

\\

) followed by a complete network path, as in

\\computer.place.com\process\folder\...folder\object

Absolute mode is, in effect, a URL. Use Absolute mode when you want to refer to a particular process on a particular computer. Any references to a

PLC, for instance, should be in Absolute mode so as to always refer to the computer physically connected to that PLC—no matter where the process making the reference is running.

Note

Though Relative mode is the LookoutDirect default, when you use an object outside the immediate location of your expression, the path becomes more specific. The addition of two periods at the beginning of a path, for instance, can be used to specify the parent of the first folder listed, as in

..\folder\object

.

You should manually change a path mode to a level beyond that strictly necessary under your current circumstances if you want to ensure that your process will still work properly if you relocate it, completely or partially.

Expressions on Control Panels

With the Insert»Expression command, you graphically display the result of an expression on a control panel. However, this method does not create an object; therefore, it does not create an output signal that other expressions or objects can use. (There is no name associated with the expression.)

You can insert this same kind of expression by dragging and dropping the data member you want to display from the LookoutDirect Object Explorer.

Note

When you insert an expression through the menu, you can explicitly choose the path relativity before you create the expression. If you insert an expression by dragging a data point from the LookoutDirect Object Explorer, the path will reflect the node you dragged the expression from. If you drag and drop an expression from the local node of LookoutDirect running on your computer, you will insert an expression with a relative path. If you drag an expression from a process under the network nodes for LookoutDirect processes (including the network node for your local computer), the expression will have an absolute path. Refer to the Path Names in LookoutDirect section for more information on LookoutDirect path modes.

The following illustration shows the Insert Expression dialog box you use to create or modify the path for a typical LookoutDirect expression.



Notice that you can set the data type for the expression to display. After you have created an expression, you can no longer modify the data type, so be sure you select the correct type for your display.

The following illustrations show typical LookoutDirect dialog boxes to select the display properties for expressions.




Expression Objects

With the Object»Create menu command, you can create an Expression object, or named expression. Like other object classes, the global

(expression) object class requires a unique name.

Other expressions and/or objects can reference the output of an (expression) object. When you need to define a unique condition that your process uses multiple times, use an (expression) object. Instead of defining the same expression in many places, you can create it one time and use its name wherever the condition applies. For example, the name

AllValvesOpen

in the following Create expression dialog box is easier to reference than the long expression.



You can also use the expression editor to assemble the long expression by right-clicking in the yellow field.

Expressions as Parameters

Many object classes accept expressions as parameters. When they do, the parameter expects the expression to return a certain signal type—numeric, logical, or text. For more information about object parameters and data members, refer to the specific object class definition in the online help.


The parameter On/off signal expects a logical expression and Timer delay requires a numeric expression. Both

Valve1

and

Valve2

are names for switches. Connecting them with and

produces a logical result and satisfies the type condition of the first parameter.

AlarmOnDelay

is the name of a potentiometer used to adjust the timer delay setpoint, which creates a numeric signal, satisfying the type condition of the second parameter.

Because the Timer delay parameter is an expression, we have many configuration possibilities, including the following:

• Enter a constant. In this case, the delay never changes.

• Enter the name of an output signal from another object such as a Pot. In this case, the operator adjusts.

• Enter a complex expression that automatically calculates the delay based on multiple inputs.



Similar configuration solutions exist for the On/off signal parameter.

When an expression parameter fields is yellow, you can get help building your expressions. For example, assume that you cannot remember whether the valve name in the previous example was

Valve1

,

Valve_1

, or

ValveOne

. If you position the cursor over the yellow expression field and right-click, the Expression Editor dialog box appears. Using this dialog box, you can select the proper name (

Valve1

) and paste it directly into the expression field. Click on OK and LookoutDirect writes the expression into the targeted parameter field.

Expressions as Connections

You can connect object data members with expressions. Writable data members accept expressions as inputs, much like parameters. To connect an expression to a data member, use the Object»Edit Connections menu command, or right-click on the object you want to connect to in the Object

Explorer, and select Edit Connections. See Chapter 4, Using LookoutDirect, of the Getting Started With LookoutDirect manual for detailed information on connecting expressions to data members.

Edit/Insert Expression Dialog Box

You can insert an expression as a display element on a control panel, use it as a parameter for a LookoutDirect object, or use it as an input data member for a LookoutDirect object. When you use an expression as a display object, you can create or modify the expression using the Insert Expression dialog box.

When you use an expression as a parameter or input to a data member, you can create or modify the expression using the Edit Expression dialog box.

These dialog boxes are almost identical, the only difference being that the

Insert Expression dialog box contains a Display Type field that you use to select how the data expression will appear on your control panel. This field does not exist in the Edit Expression dialog box because an expression being used as a parameter or as an input to an object data member will be interpreted as the data type required for that input.

Note

After you insert an expression for display, you cannot change the display type of the expression. The Display Type dialog box will be disabled if you open the expression to edit it. To change the data type, you have to insert a new expression.

You can access the Insert Expression dialog box in any of the following ways:

• Select Insert»Expression from the LookoutDirect menu.



• Click-drag an object from the Object Explorer.

• Right-click on an expression display on a control example and select

Object Properties.

• Right-click in a control panel and select Insert Expression.

You can access the Edit Expression dialog box by right-clicking in any yellow expression field in any LookoutDirect dialog box.

Except for setting a display data type in the Insert Expression dialog box, you use the two dialog boxes in the same way. The following instructions and comments apply to both dialog boxes.

Figure 1-4 shows the Insert expression dialog box. You can enter your expression in the yellow expression field at the top of this dialog box.


Just below the yellow expression field are the Display Type and Path Mode selection boxes. The Display Type box selects the data type for your expression to be displayed with (if relevant), and the Path Mode box selects how detailed the path name of your expression will be.

The lower-left field lists all objects that generate readable signals under the root shown in the root window (under the Paste button). The lower-right field lists the readable data members (Contents) for the currently selected object.

Notice that the dialog box indicates the object class selected in the object list

(Waveform) and the signal type selected in the Contents list (numeric).



You can enter an expression directly or use the Paste button to select and insert object names in the expression field. As you select different objects from the listbox, the name to the right of the Paste button changes accordingly.

Some objects have multiple readable data members, such as a Modbus object.

LookoutDirect concatenates the name, followed by a period and the selected data member.

After you combine the desired name and data member, click on the Paste button. LookoutDirect pastes the name into the expression field. Clicking on the Paste button a second time copies another instance of the name to the expression window—this time at the cursor.

Tip

Instead of selecting a data member and then clicking on the Paste button, double-click on the data member. LookoutDirect automatically pastes the name into the expression window.

You can manually type or modify a name, a data member, or a mathematical function in the expression field at any time. Because you might have many hard-to-remember, defined objects, the navigation and selection listboxes serve as a quick reference for all of your previously defined objects.

Expression Syntax

In an expression, operators are instructions to perform an operation on a value or to combine values to form a new value. For example, a simple operator is the

/

symbol. It divides one value by another; for example, the formula (

5 / 2

) reads five divided by two and produces a result of 2.5. The five and two in the preceding example are operands (the

/

operator requires numeric operands).

White Space

You can use tabs and spaces between operators, functions, and function parameters in LookoutDirect to make expressions easier to read. This manual uses spaces between operators for added clarity.

Spaces and tabs are called white space characters because they provide space between parameters. This practice is used for the same reasons that spaces are used between words and paragraphs in a book—to achieve greater organization and clarity. Because LookoutDirect ignores white space characters, you can use white space characters to separate object names in an expression. However, you cannot embed white space characters within names or alias names.



Arithmetic Operators

The following operators perform basic arithmetic operations. They require numeric operands and produce numeric results.

+

–

*

/

%

^

–

Table 1-2. Arithmetic Operators

Addition

Subtraction

Multiplication

Division

Percentage (divides preceding value by 100)

Exponentiation

Negation (additive inverse of the following value)

Text Operator

The text operator is the ampersand character (

&

). An ampersand joins two text strings. For instance, the expression

“Call me“ & “Ishmael”

produces a text signal of

Call me Ishmael

. Typical uses for the text operator include

• imbedding a numeric value within a text string

• using it in an action verification expression

• using it in an alarm message

• sending out to a remote PLC display panel

The expression

“Flow rate is” & TEXT(Flow, “0.00”)& “gpm” produces a text signal of

Flow rate is 141.23 gpm

, assuming

Flow

is a numeric signal whose value rounds to 141.23.

Comparison Operators

Comparison operators compare two numeric values and produce a logical result of either TRUE or FALSE (on or off).

Table 1-3. Comparison Operators

<

>

<=

>=

Is less than

Is greater than

Is less than or equal to

Is greater than or equal to




=

<>

Table 1-3. Comparison Operators (Continued)

Is equal to

Is not equal to

When setting up process control strategies, you often want to compare two numeric values. For example, you can use the result of the following expression to control a tank fill valve:

TankLevel<50

is TRUE while

TankLevel

is less than 50 and FALSE while

TankLevel

is greater than or equal to 50. The use of the < operator makes this a logical test, returning true or false depending on how the expression evaluates.


You can then connect this logical result to a PLC or RTU to control the fill valve so that the valve opens when the tank level drops below 50 and closes when the tank level rises above 50. Notice, however, that this method can cause the valve to fluctuate between open and closed too often if the tank level hovers around 50.

Neutralzone is an object class with built-in dead band that is more appropriate for controlling the tank fill valve. The following dialog box shows a better way to control a valve than the expression in the previous figure.



Avoid using the is equal to (=) and is not equal to (<>) comparison operators to compare an analog value from a PLC or the result of mathematical calculations in an expression. Because numeric (floating point) values have about 17 significant digits,

TankLevel = 40

might never be exactly true. If you know the signals are integer values, such as the numeric signal from the potentiometer in the following dialog box, use the = and <> operators.


In the following Create expression dialog box, a three-position switch is created with the Pot object class, where 1=Hand, 2=Off, and 3=Auto.

Next, an expression object is created that turns the pump on in two conditions: if the

HOA

switch is in the Hand position, or if the switch is in the Auto position and the

TankLevel

is less than 40.



Notice that the HOA signal is exactly 1, 2, or 3.

Tip

Pot.

You could also use the LookoutDirect Radiobutton object instead of creating an HOA

Expression Functions

There are over 50 built-in expression functions, generally classified as follows:

• logical functions

• lookup functions

• mathematical functions

• statistical functions

• text functions

• trigonometric functions

• date/time functions

• quality functions

The remainder of this chapter describes each function, specifies the syntax, and provides an example on how to use the function.

Logical Functions

AND

Syntax

Example

Description

logical1 AND logical2 AND logical3...

Switch1 AND Pot1 > 50.0

If

Switch1

is on and

Pot1

is greater than 50.0, return TRUE, otherwise return FALSE. Returns TRUE if all logical parameters are TRUE.


FALSE

IF

LIF

NIF

NOT

OR


Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

FALSE

False

Returns the logical value FALSE. Accepts no parameters.

IF (logical, result1, result2)

IF(Switch1, 99.9, Pot1)

If

logical

is TRUE, return

result1

, otherwise return

result2

. In the example, if

Switch1

is on, it outputs the value

99.9

. Otherwise, it outputs the value of

Pot1

.

LIF (logical, logical result1, logical result2)

LIF(Switch1, False, Pot1 > 50.0)

Included for compatibility with early versions of

LookoutDirect. If

logical

is TRUE, return

logical result1

, otherwise return

logical result2


Switch1

is on, it outputs the logical value

False

.

Otherwise, it returns the logical result of

Pot1 > 50.0

.

NIF (logical, numeric result1, numeric result2)

NIF(Switch1, 99.9, Pot1)


LookoutDirect. If

logical

is TRUE, return

numeric result1

, otherwise return

numeric result2


Switch1

is on, it outputs the numeric value

99.9

.

Otherwise it outputs the value of

Pot1

.

NOT (logical)

or

!logical

NOT(Switch1) or

!Switch1

If

logical

is TRUE, return FALSE, else return TRUE. In the example, if

Switch1

is on, return FALSE, but if

Switch1

is off, return TRUE.

logical1 OR logical2 OR logical3...

Switch1 OR Pot1 > 50.0

Returns TRUE if at least one logical parameter is TRUE. In the example, if either

Switch1

is on or

Pot1

is greater than 50.0, or both, the expression returns TRUE. If neither condition is true, it returns FALSE.




TIF

TRUE

XOR

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

TIF (logical, text result1, text result2)

TIF(Switch1, “Text Message”, TextInput1)


LookoutDirect. If

logical

is TRUE, return

text result1

, otherwise return

text result2

. Notice the use of quotation marks. In the example, if

Switch1

is on, it outputs

Text

Message

; otherwise, it outputs the current text value of

TextInput1

.

TRUE

TRUE

Returns the logical value TRUE. Accepts no parameters.

logical1 XOR logical2 XOR logical3...

Switch1 XOR Pot1 > 50.0

Returns TRUE if only one logical parameter is TRUE. In the example, if

Pot1

is greater than 50 and

Switch1

is on, it outputs FALSE because both logical parameters are TRUE. If

Pot1

is less than 50 and

Switch1

is on, it outputs TRUE because only one logical parameter is TRUE.

Lookup Functions

CHOOSE

Syntax

Example

Description

CHOOSE (numeric, value1, value2, value3,...)

CHOOSE(Pot1, “Switch1”, “TRUE”, “Pb1”)

Returns the value parameter corresponding to the integer portion of the numeric

parameter. If the

numeric

parameter is less than 2.0,

CHOOSE

returns

value1

. If the

numeric

parameter is greater than the number of value parameters,

CHOOSE

returns the last logical parameter listed. In the example, if the value of

Pot1

is .5, 1, or 1.4, it returns the value of

Switch1

. If

Pot1

is 2.0 or 2.8,

CHOOSE

returns the logical value

TRUE

. If

Pot1

is 3.0 or higher,

CHOOSE

returns the value of

Pb1

.



LCHOOSE

NCHOOSE

Syntax

Example

Description

TCHOOSE

Syntax

Example

Description

Syntax

Example

Description

LCHOOSE (numeric, logical1, logical2,

logical3,...)

LCHOOSE(Pot1, Switch1, TRUE, Pb1)


LookoutDirect. Returns the logical parameter corresponding to the integer portion of the numeric

parameter. If the

numeric


LCHOOSE

returns

logical1

. If the numeric

parameter is greater than the number of logical parameters,

LCHOOSE

returns the last logical parameter listed.

NCHOOSE (numeric, numeric1, numeric2,

numeric3,...)

NCHOOSE(Pot1, Pot2, Pot3, 14.3)


LookoutDirect. Returns the

numericx

parameter corresponding to the integer portion of the numeric

parameter.

If the

numeric


NCHOOSE

returns

numeric1

. If the

numeric

parameter is greater than the number of

numericx

parameters,

NCHOOSE

returns the last

numericx

parameter listed.

TCHOOSE (numeric, text1, text2, text3,...)

TCHOOSE(Pot1, “Auto”, “Manual”, “Local”,

“Locked”)


LookoutDirect. Returns the text parameter corresponding to the integer portion of the

numeric

parameter. If the

numeric


TCHOOSE

returns

text1

. If the

numeric

parameter is greater than the number of text parameters,

TCHOOSE

returns the last logical parameter listed.

Mathematical Functions

ABS

Syntax

Example

Description

ABS(numeric)

ABS(Pot1 – 50.0)

Returns the absolute value of

numeric


Pot1

is zero, the function returns

50.0

.




EXP

FACT

INT

LN

LOG

LOG10

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

EXP(numeric)

EXP(Pot1)

Returns the base of the natural logarithm, e (2.71828182), raised to the power of

numeric


Pot1

is 2.0, the function returns 2.71828182

2

or approximately 7.38906.

EXP is the inverse of the function, LN. To calculate the values of other powers, use the exponentiation operator ( ^ ).

FACT(numeric)

FACT(4.2)

Returns the factorial of the integer portion of

numeric

. In the example, the function returns the factorial of 4, or 1*2*3*4, or

24. The factorial of zero, FACT(0), or any number less than zero is one (1).

INT(numeric)

INT(4.2)

Rounds

numeric

down to the nearest integer. In the example, the

INT

function returns 4. Notice also that

INT(–8.5) = –9

.

See also TRUNC.

LN(numeric)

LN(PLC.AI1)

Returns the natural logarithm of

numeric


PLC.AI1

= 1000.0, the function returns 6.90776.

LOG(numeric1, numeric2)

LOG(Pot1,2)

Returns the logarithm of

numeric1

to the

numeric2

base, where

numeric1

is a positive real number. In the example, if

Pot1


LOG10(numeric)

LOG10(Pot1)

Returns the base-10 logarithm of

numeric

, where

numeric


Pot1




MOD

PI

PRODUCT

RAND

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

ROUND

SIGN

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

MOD(numeric1, numeric2)

MOD(50,8)

Returns the modulus (remainder) of

numeric1

divided by

numeric2

, where

numeric2

is not equal to zero. In the example, 50 divided by 8 equals 6 with a remainder of 2.

Therefore, the function returns 2.

PI()

PI()

Returns an approximation of PI: 3.1415927. Accepts no parameters.

PRODUCT(numeric1, numeric2, numeric3,...)

PRODUCT(2,4,6,10)

Returns the product of all the numerics. In the example, the function returns 2*4*6*10 or 480.

RAND()

RAND() * Pot1

Generates a new random number between zero and one every time the formula that this function is a part of is recalculated.

Accepts no parameters. In the example, every time the value of

Pot1

changes, the function generates a new random number and multiplies it by the value of

Pot1

.

ROUND(numeric1, numeric2)

ROUND(Pot1,2)

Rounds the value of

numeric1

to

numeric2

decimal places.

In the example, if

Pot1

equals 15.745, the function returns

15.75. If

numeric2

equals zero, the function returns an integer.

If

numeric2

is less than zero, the function returns zero.

SIGN(numeric)

SIGN(Pot1)

Returns 1 if

numeric

is positive, 0 if

numeric

is 0, –1 if

numeric

is negative. In the example, if

Pot1

is –0.00001, the function returns –1.




SQRT

TRUNC

Syntax

Example

Description

Syntax

Example

Description

SQRT(numeric)

SQRT(ABS(Pot1))

Returns the square root of

numeric

, where

numeric


Pot1

is –25.0, the absolute function first converts the Pot value to positive 25 and the square root function calculates 25 = 5.

TRUNC(numeric)

TRUNC(8.9)

Truncates

numeric

to its integer component by removing its fractional part. In the example, the

TRUNC

function returns 8.

Notice also that

TRUNC(–8.9) = –8

. See also INT.

Statistical Functions

AVG

Syntax

Example

Description

MAX

MIN

Syntax

Example

Description

Syntax

Example

Description

AVG(numeric1, numeric2, numeric3,...)

AVG(2,4,–6,12)

Returns the arithmetic mean (average) of all the numerics listed. This function requires at least two numeric parameters.

In the example, the function returns (2 +4– 6+12) / 4 or 3.0.

MAX(numeric1, numeric2, numeric3,...)

MAX(2,4,–6,12)

Returns the highest value of all the numeric values listed. This function requires at least two numeric values. In the example, the function returns 12.

MIN(numeric1, numeric2, numeric3,...)

MIN(2,4,–6,12)

Returns the lowest value of all the numeric values listed. This function requires at least two numeric values. In the example, the function returns –6.


STDEV

STDEVP

SUM

VAR

VARP


Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

STDEV(numeric1, numeric2, numeric3,...)

STDEV(2.9,4.5,5.0,4.3,3.8)

Returns the sample standard deviation of the numeric values listed. (Standard deviation is a measure of dispersion, calculated as the positive square root of the variance.) This function calculates the standard deviation using the non-biased or n–1 method. This function requires at least two numeric values. In the example, the function returns 0.796869.

STDEVP(numeric1, numeric2, numeric3,...)

STDEVP(2.9,4.5,5.0,4.3,3.8)

Returns the standard deviation of a full population of numeric values. This function calculates the standard deviation using the biased or n method. This function requires at least two numeric values. In the example, the function returns 0.712741.

SUM(numeric1, numeric2, numeric3,...)

SUM(2,4,–6,12)

Returns the sum of all the numeric values listed. This function requires at least two numeric values. In the example, the function returns 12.

VAR(numeric1, numeric2, numeric3,...)

VAR(2.9,4.5,5.0,4.3,3.8)

Returns the sample variance of the numeric values listed.

(Variance is a measure of dispersion.) This function calculates the variance using the non-biased or n–1 method. This function requires at least two numeric values. In the example, the function returns 0.635.

VARP(numeric1, numeric2, numeric3,...)

VARP(2.9,4.5,5.0,4.3,3.8)

Returns the population variance of the numeric values listed.

This function calculates the variance using the biased or n method. This function requires at least two numeric values.

In the example, the function returns 0.508.




Text Functions

EXACT

FIND

FIXED

LEFT

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

EXACT(text1, text2)

EXACT(TextEntry1, “batch a”)

Returns TRUE if

text1

exactly matches

text2

, otherwise returns FALSE. This function is case sensitive. In the example, the function returns TRUE if the text result of

TextEntry1 exactly matches batch a

(notice that the entry in this example is all lowercase).

FIND(text1, text2, numeric)

FIND(“ON”, ”Reactor A is ON”, 1)

Searches for

text1

within

text2

starting after

numeric

characters, and returns the position of the first character where the match begins. This function is case sensitive. The output of this function is numeric. It returns 0 if no match is found. In the example, the function searches the entire string for the word,

ON

and returns 14, indicating the position of the first character of the word. Also see SEARCH.

FIXED(numeric1, numeric2)

“The flow is” & FIXED(Pot1,2)

Rounds the value of

numeric1

to

numeric2

decimal places and then converts

numeric1

to a text string. In the example, if the value of

Pot1

equals

123.456

, the

FIXED

function returns the text value

123.46

. Thus, the entire text string would read

The flow is 123.46

. If

numeric2

is negative or omitted,

numeric1

is rounded to the nearest whole number. For example,

FIXED(123.588)

returns

124

.

See also TEXT.

LEFT(text, numeric)

LEFT(“Reactor A is ON”, 9)

Retrieves the specified number of characters from the lefthand end of

text

and outputs it as a text value. In the example, the function returns

Reactor A

.



LEN

LOWER

MID

PROPER

REPLACE

REPT

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

LEN(text)

LEN(“Reactor A is ON”)

Returns the length of the text string (the number of characters in

text

). In the example, the function returns the numeric value 15.

LOWER(text)

EXACT(LOWER(TextEntry1), “batch a”)

Converts

text

to all lower case. In the example, the

LOWER function ensures that a match is found whether

TextEntry1 content reads

Batch A

,

BATCH A

, or batch A

.

MID(text, numeric1, numeric2)

MID(“Reactor A is ON”,9,7)

Retrieves

numeric2

characters from

text

, beginning at character

numeric1

. In the example, the function returns the text value

A is ON.

PROPER(text)

PROPER(“reactor A is ON”)

Capitalizes the first character of each word in

text


Reactor A

Is On.

REPLACE(text1, numeric1, numeric2, text2)

REPLACE(“Reactor A is ON”, 9, 1, “B”)

Replaces

numeric2

characters with

text2

beginning with character

numeric1

in

text1


Reactor B is ON.

REPT(text, numeric)

REPT(“LookoutDirect”, Pot1)

Repeats

text numeric

times. In the example, if the value of

Pot1

is 8, the function returns the text value,

LookoutDirect

LookoutDirect LookoutDirect

LookoutDirect LookoutDirect LookoutDirect

LookoutDirect LookoutDirect.




RIGHT

SEARCH

TEXT

TRIM

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

RIGHT(text, numeric)

RIGHT(“Reactor A is ON”, 7)

Retrieves the specified number of characters from the righthand end of

text

and outputs it as a text value. In the example, the function returns the text value

A is ON

.

SEARCH(text1, text2, numeric)

SEARCH(“on”, ”Reactor A is ON”, 1)

Finds

text1

within

text2

beginning at

numeric

character, and returns the position of the first character where the match begins. This function is not case sensitive. The output is numeric. It returns 0 if no match is found. In the example, the function searches the entire string for the word

ON, on, On, or oN

and returns 14, indicating the position of the first character of the word. Refer also to FIND.

TEXT(numeric, text)

TEXT(Pot1, “0.00”)


LookoutDirect. With polymorphic data, this function becomes unnecessary. Like

FIXED

, the

TEXT

function converts

numeric

to a textual value. While

FIXED

allows you to specify the number of decimal points,

TEXT

allows you specify a desired numeric format in the text parameter. If

Pot1

equals

12.3456, the function would return the textual value

12.35

.

See Numeric Formats in Chapter 5, Developer Tour, in your

Getting Started with LookoutDirect manual. See also FIXED.

TRIM(text)

TRIM(“Reactor A is ON”)

Trims multiple spaces from between words. In the example, there are multiple spaces on either side of the word, A. This function returns

Reactor A is ON

, eliminating all repeated spaces.



UPPER

Syntax

Example

Description

UPPER(text)

UPPER(text)

Converts

text

to all capital letters (upper case). In the example, the

UPPER

function ensures that a match is found whether

TextEntry1

content reads

Batch A

,

BATCH A

, or batch A

.

Trigonometric Functions

ACOS

Syntax

Example

Description

ASIN

ATAN

Syntax

Example

Description

Syntax

Example

Description

ACOS(numeric)

ACOS(Pot1)

Returns the arccosine of

numeric

(that is, it returns the angle of the cosine you specify as

numeric

).

Numeric

must range between –1 and 1. The result is output in radians and ranges from 0 to

π


Pot1

= 0.5, the function returns

1.0472 radians (60 degrees). You can express the arccosine in degrees by multiplying the result by 180/

π

.

ASIN(numeric)

ASIN(Pot1)

Returns the arcsine of

numeric

(that is, it returns the angle of the sine you specify as

numeric

).

numeric

is the sine of the angle and must range between –1 and 1. The resulting value is given in radians and ranges from –

π

/2 to

π

/2. In the example, if

Pot1

= –1, the function returns –1.5708.

ATAN(numeric)

ATAN(Pot1)

Returns the arctangent of

numeric

(that is, it returns the angle of the tangent that you specify as

numeric

). The resulting value is given in radians and ranges from –

π

/2 to

π

/2. In the example, if

Pot1

= 180, the function returns 1.56524 radians

(about 90 degrees).




ATAN2

COS

SIN

TAN

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description

ATAN2(numericX, numericY)

ATAN2(5, 5)

Returns the arctangent of the specified x- and y-coordinates

(that is, it returns the angle of a line extending from the origin

(0,0) to a point specified by the

numericX

,

numericY

coordinate pair that you specify). The resulting value is given in radians and ranges from greater than –

π

to

π

. In the example, the function returns 0.785398 radians (45 degrees).

COS(numeric)

COS(Pot1)

Returns the cosine of

numeric

where

numeric

is the angle in radians. In the example, if

Pot1


0.500171. You convert degrees to radians by multiplying by

π

/180.

SIN(numeric)

SIN(Pot1)

Returns the sine of

numeric

where

numeric

is the angle in radians. In the example, if

Pot1


1.2246E–16 (effectively zero). You convert degrees to radians by multiplying by

π

/180.

TAN(numeric)

TAN(Pot1*PI()/180)

Returns the tangent of

numeric

where

numeric

is the angle in radians. In the example, the value of

Pot1

is 45, but it is in degrees, not radians. Convert it to radians by multiplying it by

π

/180. In this example, the function returns 1.



Date/Time Functions

NOW

TODAY

Syntax

Example

Description

Syntax

Example

Description

NOW(logical)

NOW($Keyboard.F1)

Returns a numeric value representing the current system date and time when any signal within the parentheses changes. The result is a floating point number in which the integer represents the date and the fraction represents the time of day. In the example, when you press the function key <F1>, the date and time are output as a single number, like 34738.3. If you change the Numeric Format of the number to mm/dd/yy hh:mm:ss

, the same number would be shown as

02/08/95 07:49:02

.

TODAY(logical)

TODAY($Keyboard.F1)

Returns a numeric value representing the current system date when any signal within the parentheses changes. The result is an integer that represents the number of days that have passed since Jan. 1, 1900. In the example, when you press the function key F1, the date is output as a single number, such as

34738

. If you change the Numeric Format of the number to mm/dd/yy

, the same number would be shown as

02/08/95

.

Note

If you want to display the current time only, subtract the

TODAY

function from the

NOW function.

Example:

NOW($Keyboard.F1) – TODAY($Keyboard.F1)

In this example, if you want the result to update itself every second, replace

$Keyboard.F1

with a one second pulse timer.

Quality Functions

LookoutDirect monitors data quality and informs you if the data quality has gone bad. When you display data on a control panel directly through an expression, or when an object with a displayable element is connected to some other object and receives bad data, the quality problem is indicated by a red X that LookoutDirect superimposes over the display.

Some data members might not be displayed or may not connect to an object on some particular panel, but you may still need to monitor the quality of that data. You can use the qgood

and qbad

functions for a quick check of quality.




qtext qgood qbad

Also, although a red X tells you there is a data quality problem, you might need more specific information about what has actually gone wrong with the data. You can use the qtext

function to report the specifics of what has gone wrong.

Syntax

Example

Description

Syntax

Example

Description

Syntax

Example

Description qtext(expression, [delimiter]) qtext(modbus.40001, "AND")

Returns a text string specifying what elements of data quality have gone bad.

qgood(expression) qgood(modbus.40001)

Returns TRUE while the expression is good.

qbad(expression) qbad(modbus.40001)

Returns TRUE while the expression is bad.


2

Graphics

This chapter describes how to add static and dynamic graphics to a control panel and how to create and use custom graphics.

Any visible item on a LookoutDirect control panel is a graphic. All graphics are either static or dynamic. Static graphics never change state, but dynamic graphics change state to represent process variations. LookoutDirect provides an extensive graphics library. These graphics range from switches, potentiometers, and pushbuttons to bar graphs, valves, tanks, pumps, plates, insets, scales, and more. However, there might be times when the standard

LookoutDirect graphics do not exactly fit your needs. You can use any other drawing software to create your own custom graphics.

Note

Consider screen resolution when creating display panels (VGA versus Super VGA).

The same panel appears differently on computers using different resolution display drivers.

Read about screen resolutions in the description of Panel objects in the online help or the online PDF LookoutDirect Object Reference Manual before you design your panels.

Setting Snap to Grid

You can activate the snap to grid feature in LookoutDirect by selecting

Edit»Snap to grid. This feature aligns objects you are positioning to a grid on the LookoutDirect panel.

You can adjust this grid by selecting Edit»Options. The Edit Options dialog box appears.



Chapter 2 Graphics

Static Graphics

Use this dialog box to set the distance (in pixels) between grid points, show or hide the grid, and select different color options for the grid display.

Static graphics never change state. They exist on a control panel much the same way a picture hangs on your wall, never changing or moving. Static graphics range from text labels, plates, insets, and scales to complex schematic overviews and scanned photographic images.

Displaying Text, Plates, Insets, Rectangles, and Lines

Effective use of text, plates, and insets make control panels intuitive and easy to use. The example below demonstrates how plates and insets organize information about two pumps.

Plate

Inset


To create static text, plates, insets, rectangles, or lines in LookoutDirect, select Insert»Text/plate/inset. The Insert text/plate/inset dialog box appears.



If you want to create a rectangle, line, plate, or inset, leave the Text field blank and choose a Background style. The preview window displays the element as it appears on a control panel.

To create a vertical or horizontal line, choose Rectangle. After clicking on OK, size the rectangle to the desired length, and reduce the width to the thickness you want your line to be. If you need the rectangle an exact size, use the yellow status bar, which indicates dimensions.

Note

LookoutDirect uses color grids in many dialog boxes. The grids make selecting colors quick and visually helpful. However, they might look slightly different from computer to computer.

Some computer display adapters can display only 16 solid colors on the screen. The standard VGA adapter in conjunction with the Windows VGA driver supports only 16 colors directly. Windows uses a technique called

dithering to simulate the display of colors not directly supported as solid colors. For example, LookoutDirect might display orange as an alternating pixel pattern of red and yellow bits on the screen.

Some objects in LookoutDirect require solid colors, so if you specify a dithered color, LookoutDirect uses the nearest solid color instead. For example, a Trend object requires a solid color for its background and solid colors for the trend lines. Furthermore, LookoutDirect always displays text in a solid color. If you specify pastel green for a trend line color, you might get yellow instead. Bar graphs and control panel backgrounds can display dithered colors.




Note

Some display adapters support 256 or even 16 million colors on the screen at one time.

Even though LookoutDirect allows you to specify only 28 colors, LookoutDirect displays custom graphic files on control panels using all available colors.

Displaying Static Custom Graphics

LookoutDirect supports two graphical file types—Windows

Device-Independent Bitmap (

.BMP

) and Windows Metafile (

.WMF

).

To display static bitmap and metafile graphic files on a control panel, select the Insert»Graphic command. The Select graphic dialog box appears.

From the Select graphic dialog box, you can scroll through various directories containing a variety of graphic files. The list box includes all bitmaps and metafiles located in the

GRAPHICS

subdirectory under the root

LOOKOUTDIRECT

directory. As you select each category, you see thumbnail sketches displayed in the preview window to the right of the list box. Because graphics might stretch or shrink to fit in the preview window, they might not appear exactly as they do on a control panel.

Note

If you know the name of the file, type the first letter of the filename. The list box automatically scrolls to the first file beginning with that letter.

If you choose a bitmap (

.BMP

) file, you can use the Transparent pixel data fields to specify which color pixels in that graphic you want to be



transparent in LookoutDirect. Imagine the viewing area as an X-Y coordinate plane with (0,0) being the top left corner of the graphic (not the entire viewing area). You can enter any X and Y coordinates, and the corresponding pixels become transparent, as do all other pixels that color. The Transparent pixel fields do not have any default values. If you leave the X and Y fields blank, no pixels become transparent.

You can use a multicolor bitmap as a type of mask. For this to work, some part of the bitmap (usually the interior) must be transparent and the rest of the graphic opaque—masking the underlying part of the control panel. In the case of the interface selected above (the second from the left in the second row), the pixels to be made transparent are gray. You can insert another

LookoutDirect element, such as a bar graph, to furnish a convenient visual warning, such as a rising color level.

You could guess the X,Y coordinates of any grey pixel on the graphic. It helps to know that the center of the graphic is (

–1

,

–1)

. In the example above,

(–1

,

–1)

is a black pixel; to select a gray pixel, you would have to offset your choice to

(–1

,

0)

. Because this is a gray pixel, all other gray pixels become transparent when inserted on a control panel.

Note

Windows metafiles are normally easier to use and manipulate than bitmap images. Unlike bitmaps, metafiles can be resized in LookoutDirect. Because of their inherent structure, you can also use metafiles as masks without specifying transparent pixels. Had the




example above used a

.WMF

graphic, the area in gray would have appeared in the

LookoutDirect window as a crosshatched area.

Dynamic Graphics

Many process control panels require some type of animation, such as a pump changing colors to represent on and off. Table 2-1 lists the LookoutDirect elements that use animation or change states.

Table 2-1. Tools for Displaying Dynamic Graphics

LookoutDirect

Component

Animator object class

Description

An Animator object provides full graphical animation including horizontal and vertical motion, dynamic resizing and visibility, dynamic sequencing, and color changing.

Multistate object class

Pipe object class

DialGauge object class

Gauge object class

Spinner object class

A Multistate object displays up to six different custom graphics based on advanced if-then-else logic.

A Pipe object makes a rectangle or line (of any dimension) change colors or blink, based on advanced if-then-else logic.

A DialGauge object displays a numeric signal as a sweeping needle on an analog gauge or dial.

A Gauge object makes a numeric expression (digital number or barchart) change colors or blink based on advanced logic.

Switch object class

Pushbutton object class

Pot object class

A Spinner object is a small rotating disk. It can be turned on and off with a logical signal, and its rotation speed and direction are controlled by a numeric value.

A Switch object can represent its two positions using standard switch symbols or custom graphics.

A Pushbutton object looks like a button that changes when depressed, but you can also make it transparent. You might use transparent pushbuttons over custom graphics.

A Pot object can be displayed as a knob, vertical slider, horizontal slider, increment and decrement buttons, or a digital number.

Logical expression When you create an expression that results in a logical value, you can represent that value using standard lights, text, or custom graphics.



Table 2-1. Tools for Displaying Dynamic Graphics (Continued)

LookoutDirect

Component

Numeric expression

Text expression

Description

When you create an expression that results in a numeric value, you can represent that value using a digital number or a vertical or horizontal bar chart.

When you create an expression that results in a text value, you can represent that value using any style and size font loaded on your computer.

For information on a specific object class, refer to the online help or the online

PDF LookoutDirect Object Reference Manual. For information on expressions, refer to Chapter 1, Expressions.

Displaying Dynamic Logical Signals

Logical expressions and Switch objects are two commonly used graphical animation tools. You can display the signal a Switch object generates in a variety of ways.

Switch ON

Switch OFF


The Switch is shown in the On and Off positions. The graphics on the right side of the control panel show three ways of graphically displaying the logical signal generated by the Switch. The graphics representing the Switch signal are expressions of the

(implicit)

value of the switch, created through the

Insert»Expression menu command.



To create a Switch object, first choose the logical signal that you want to represent with dynamic graphics (for example, a logical input from a PLC).

Then, select an object to display the logical signal. For this example, use a

Switch to simulate a contact from a motor starter relay.

Create a Switch and call it

PumpSwitch

. After you define the Switch parameters, LookoutDirect presents the display parameters dialog box for the

Switch object (as shown in the following figure). You can choose to represent

PumpSwitch

with one of the standard graphics, or you can use custom graphics. For this example, select a standard graphic and click on OK.

To insert an expression representing the signal generated by the Switch object, use the Insert»Expression command and select

PumpSwitch

, or drag and drop the signal from the LookoutDirect Object Explorer.



When you click on OK, the Display logical signal dialog box appears. From the Display logical signal dialog box, select display characteristics for a logical signal expression.


Click on the Custom selection, and then on the On and Off list boxes, scrolling through the choices until you find the appropriate graphic. Your On and Off graphic selections appear as thumbnail sketches in the two preview windows to confirm and verify your selection.



Click on OK and test your example by flipping the switch. The graphics should change according to your selections in the On and Off preview windows. To customize your switch, experiment with the Text selection in the Display logical signal dialog box.

Use this same basic method to display any dynamic signal on a control panel.

If you want to represent more than two conditions with dynamic graphics, use a Multistate object. Similarly, you can use a Pipe object to make a line or rectangle dynamically change colors and blink.

Displaying Dynamic Numeric Signals

You can use a Pot object to display dynamic numeric signals. The following illustration shows the Pot as a slider, a digital entry, and increment and decrement buttons—all are graphical representations of the same Pot object.

Slider

Bar Graph Display

Digital Entry

Increment Decrement

To use a Pot object to display a signal, first choose the numeric signal that you want to represent with dynamic graphics, such as an analog input from a PLC.

Then, select an object to graphically display the dynamic numeric signal. For this example, create a Pot object and name it

PumpSpeed

. After you define the Pot parameters, a display parameters dialog box appears. In this example, the dialog box is named Insert: Pot1. You can choose to represent the Pot with any of the standard graphics.



Use the Insert»Expression command (or click and drag) and select

PumpSpeed

to insert an expression that represents the signal generated by the

Pot object.

When you click on OK, the Display numeric signal dialog box appears.

From this dialog box, select the display characteristics for a numeric signal expression.

If you choose Digital display style, you can use the Font button to select the desired font style and size. You can also specify a Numeric format for the value. For more information on numeric formats, refer to the LookoutDirect

Getting Started Guide, Chapter 3, Getting Started with LookoutDirect


Click on OK and test your example by adjusting the Pot. The graphics should change according to your selections.

If you want to represent the numeric signal with moving custom graphics, use the Animator object class.



Displaying Dynamic Text Signals

You can display dynamic text messages on a control panel with text expressions. You can easily display up to two separate text messages using logical signals, but there are times when you need to display three or more separate text messages in a single statement. If you have more than two separate messages, a numeric signal might determine which message to display.

To graphically display a dynamic text signal, first choose the numeric signal that you want to use to control which message is displayed, perhaps an analog input from a PLC. Then, select a graphical object to display that signal. This example uses a Pot object.

Create a Pot object and call it

Pot1

. Define the Pot minimum, maximum, and resolution parameters as 1, 4, and 1 respectively. Select the

Insert»Expression command and enter the following expression in the dialog box that appears.

TCHOOSE(Pot1, “Do you recall”, “Those roadside signs”,

“That used to promote”, “Burma Shave”

.

See Chapter 1, Expressions, for information on the TCHOOSE function.



When you click on OK, the Display text signal dialog box appears. From this dialog box, select display characteristics for a text signal expression. Use

Plate as your background style.

Click on OK and test your example by adjusting the Pot. The text should change according to your expression.

Finding a Lost Graphics File

LookoutDirect uses a standard missing graphics bitmap to mark a location on a panel where a graphic should be present but cannot be found in the location

LookoutDirect expects. The status bar at the bottom of the LookoutDirect screen displays the path and filename of the missing graphic.

Right-clicking on the missing graphic bitmap displays a standard screen that also tells you the name of the missing graphics file and the previous path.

To restore the look of your panel, either put a new copy of the graphic in the location in which LookoutDirect expects to find it, or delete the missing graphic bitmap and place a new copy of the graphic from its current location.




Creating Custom Graphics

There might be times when none of the LookoutDirect standard graphics exactly fits your needs. You can use any drawing software to create your own custom graphics. LookoutDirect supports both Windows

Device-Independent Bitmaps (

.BMP

) and Windows Metafiles (

.WMF

).

After you create a custom graphic file, copy it to the

GRAPHICS

subdirectory of your choice in your LookoutDirect root directory. Because LookoutDirect can use only graphics located in the

GRAPHICS

directory and subdirectories, keep all standard and custom graphics in the

GRAPHICS

subdirectories.

LookoutDirect can access your custom graphic file any number of times in the same or different process files from the

GRAPHICS

subdirectories.

Creating Custom Graphics Example

This section describes how to create custom graphics for use in

LookoutDirect. This example sketches out the creation of an elevated tank graphic you can use to show water level in a real tank. You export that tank graphic to LookoutDirect, implement the display in LookoutDirect, and test it. The example might only parallel what you would have to do with your own graphics creation program, but should serve as an illustration of the important points.

If you have not already mastered using a drawing program, you should allow yourself time to become accustomed to using the drawing application of your choice. The illustration below is from a third-party drawing application.

Creating the Graphic

1.

Draw half of the tank.

2.

Copy the tank half and mirror the image to create the other half.

3.

Connect and refine the halves to create an enclosed tank object.



4.

Refine your image until it looks the way you want.

5.

Draw a rectangle around the tank and connect both the rectangle and tank into a single object.

6.

To match the background color of the mask to the control panel, select the object group and click on the gray color bar selection.

7.

Select invisible for the line style.




Save or Export the Graphic and Place in Lookout

Direct

1.

Save or export your new graphic from the drawing program as a

Windows Metafile (.

WMF

) in the directory

C:\LOOKOUT\GRAPHICS\TANKS

and name your new graphic

ELEVTANK.WMF

.

2.

Export.

Testing the Graphic in Lookout

Direct

1.

Launch LookoutDirect.

2.

Create a Pot object using the Object»Create command.

3.

Select Insert»Expression, choose the Pot object, and click on OK.

4.

In the Display numeric signal dialog box, select Bar (up) for the

Display style, Rectangle for the Background Style, and click on OK.


5.

Use the Insert»Graphic command to insert your new graphic,

ELEVTANK.WMF

, over the bar graph.

6.

Position the graphic over the bar graph and stretch it to size.

7.

Toggle out of edit mode and test your example by moving the slider up and down.






Graphic File Types

LookoutDirect accepts both Windows Device-Independent Bitmaps (

.BMP

) and Windows Metafiles (

.WMF

).

Bitmaps

Bitmaps are raster files, made up of differently colored pixels. Because each pixel in the bitmap takes up one pixel on the screen, bitmap images are always rectangular and never resizable. You can display raster images on control panels that are not rectangular in LookoutDirect by using transparent pixels for the parts of the rectangle you do not want to show.

Bitmap files typically have a

.BMP

file extension. The Paint program that comes with Windows can read

.PCX

bitmap files (another very common bitmap format) and convert those files to Windows bitmaps.

Metafiles

Metafiles are vector files, consisting of coordinates that are connected by lines and curves, as well as area-fill commands. A vector file can consist solely of two sets of coordinates connected by a line or a complex set of colored area fills and colored lines and curves to create line art images.

Metafile images are not necessarily rectangular.

Because metafiles contain a set of coordinates, they can be resized and stretched to any size or aspect ratio. Microsoft does not add information in the basic metafile file format for metafile size information. The Aldus

Corporation (authors of PageMaker) created a metafile header that contains metafile size information. Most software packages that generate metafiles also add this header information. Without the header, LookoutDirect cannot maintain the correct aspect ratio (width to height ratio) for a metafile. To determine if a metafile has this information, resize the graphic on a control panel while holding down <Ctrl>. If aspect information is available,

LookoutDirect does not stretch the metafile drawing out of proportion.

Bitmaps or Metafiles?

Which format is better: bitmap or metafile? Both have strengths and weaknesses. You might want to use a combination of metafiles and bitmaps.

Bitmaps effectively handle large background schematics or system overviews, and metafiles work well for individual pumps, valves, lamps, and other miscellaneous graphics.



Bitmaps usually display faster than metafiles. In fact, a complex drawing rendered as a bitmap can display 100 times faster than the corresponding metafile. If you want to display scanned photographic quality images with hundreds of colors, use bitmaps.

Metafiles are resizable—you can stretch them to any size or aspect ratio.

Metafiles are typically smaller than bitmap files, so they take up less disk space and consume less memory than bitmap files. You can use one file that contains a metafile drawing of a pump to display several pumps of various sizes on the screen. With most drawing programs, you can save your line art images as metafiles. You can also copy the image on screen to the Windows clipboard and paste it into a paint program for bitmap conversion.

Memory Considerations

LookoutDirect loads each graphic into computer memory the first time it is displayed. The image remains in memory until LookoutDirect or another application needs more memory than is available. When more memory is needed, the graphic is discarded from memory and reloaded from disk the next time it is displayed, so that you can display more bitmaps and metafiles on the screen than can be held in memory at one time.

If you are running Windows in enhanced mode on a 386 or 486 computer, you have virtual memory. Windows uses virtual memory to swap memory images between RAM and disk, giving applications the appearance of more memory.

If available memory becomes low and Windows must use virtual memory to handle applications and data between disk and memory, you might notice a slower application speed. For more information on virtual memory, refer to your Windows user guide. If your computer disk drive light flashes every time you pull up a new control panel in LookoutDirect, consider purchasing more RAM.





3

Serial Port Communication Service

This chapter describes serial communications and describes how to define settings for three different serial connections: hardwired, radio (RTS/CTS), and dial-up.

Introduction to Driver Objects

Certain object classes represent and communicate with external physical devices such as PLCs, RTUs, and controllers. A few examples include

Modbus, Tiway, AB_PLC5, and Optomux. We use the generic term driver to refer to these types of object classes. The functionality built into driver objects enables them to communicate with the physical devices that they represent.

LookoutDirect communicates with the outside world primarily through driver objects.

In traditional systems, drivers are separate applications that run independently of the operator interface. Driver programs compete for CPU time with applications such as database managers, HMIs, and historical data loggers, necessitating multitasking and increased CPU power. In contrast,

LookoutDirect drivers are not separate applications. LookoutDirect driver objects work as any other object in the LookoutDirect event-driven environment, except that they communicate with external devices.

With traditional systems, you assign a particular driver to a specific serial port. In such configurations, multiple drivers cannot share a single serial port.

LookoutDirect does not associate baud rate, data bits, parity, or stop bits with a particular serial port. In this way, drivers that implement different protocols and baud rates can use the same port and the same modem or radio frequency.

This capability allows you to mix and match RTUs, PLCs, and other devices over a single radio frequency without communication conflicts or special hardware. For example, you can use a single two-way radio connected to a serial port to communicate with several different brands of RTUs out in the field, each one using a different protocol. You can have seventy-five remote

PLCs share a set of five dial-up modems.



Chapter 3 Serial Port Communication Service

All this is possible because of the LookoutDirect port communication service.

Objects use the communication service, an environment service, to gain access to serial ports in an orderly and timely fashion.

Note

Some LookoutDirect driver objects communicate with physical devices through dedicated hardware. These driver objects do not use serial ports but instead rely on their own proprietary network cards to communicate with the outside world. A few examples include

Modbus Plus (SA85 card), Data Highway (KT card), and DeltaTau (PMAC card). You do not need to configure serial ports for these objects classes. Refer to the appropriate object class documentation in you online help or in the PDF LookoutDirect Object Reference Manual to verify if a particular object class uses a serial port.

Understanding the Communication Service

The LookoutDirect serial communication service allocates serial port usage between driver objects. At the frequency of the object Poll Rate, a driver object notifies the communication service that it needs to use a specific serial port to poll a device. If the requested serial port is not in use, LookoutDirect allocates the serial port to the driver object. When the driver object takes control of the serial port, it defines port communication parameters such as baud rate and protocol and polls its device. When polling is complete, the driver object releases the port so the communication service can allocate it to other driver objects.

You can uniquely configure each serial port for hardwired, radio, or dial-up communications through the Serial Port Settings dialog box. Refer to the

Defining Serial Port Settings section for more detailed information.

Note

You must define serial port communication settings on every copy of LookoutDirect.

If you have more than one instance of LookoutDirect running on the same computer, each instance must use a different serial port.

Because multiple LookoutDirect applications cannot share the same serial port, if it is necessary for two processes to access the same serial port, they need to be run in the same

LookoutDirect application. If you are designing a system with multiple server process files, and those server files all access the same serial port on a single computer, they need to be run in the same LookoutDirect application.



Defining Serial Port Settings

This section walks you through the steps to configure serial port settings for hardwired, radio, and dial-up communications.

1.

From the LookoutDirect menu bar, select Options»Serial Ports. The

Serial Port Settings dialog box appears.

2.

In the Serial port data field, select the communication port you are defining.

3.

Define the serial port parameters for the appropriate communication port. The rest of this section contains complete descriptions of the parameters.

4.

Click on Accept to save the parameter changes for the serial port.

5.

Click on Quit to exit the dialog box.

Selecting the Serial Port

Use the Serial port field to select the communication port you are defining.

Microsoft Windows supports up to nine serial ports; however, most computers support only two serial ports without additional hardware.

Setting Receive Gap

The Receive gap setting is available for all serial connection types.

This number specifies the number of empty bytes (or amount of time) a driver receives from a controller before the driver recognizes the end of a message frame and asks for another message. Normally you should leave this at the default setting of 5. However, if you are experiencing garbled communication alarms, you might try increasing this number to allow more dead time before




LookoutDirect decides it has received a complete message. For example, with a slow baud rate of 1200, you might have to increase the Receive gap setting to approximately 30.

Selecting the Serial Connection

Hardwired Settings

Hardwired serial connections require no hardware handshaking for line control. Use this setting for all serial communication types except dial-up telephone and remote radio transceivers. You should also use this setting when directly connecting LookoutDirect to the master repeater on a radio system or through a leased-line modem. Because a master repeater is a full-duplex device that does not require keying and unkeying of the frequency, it acts much like a physically hardwired network. Other hardwired connection types include RS-232, RS-422, RS-485, and leased telephone lines.

RTS/CTS Handshaking Settings

RTS/CTS is a local hardware handshaking mechanism between the local computer and the local communication device. Use the Radio (RTS/CTS) serial connection when you connect the serial port to a device that requires

RTS/CTS hardware handshaking, such as a radio transceiver that must be keyed up during data transmission and unkeyed during data reception. Other half-duplex communication media, such as RS-485, might require RTS/CTS hardware handshaking. Although the RTS/CTS scheme works identically for other RTS/CTS communication schemes, this example assumes that you are communicating through radio.

When you select RTS/CTS hardware handshaking, LookoutDirect controls the RTS, or request-to-send pin, and monitors the CTS, or clear-to-send pin, during data transmission (pins 4 and 5 on a 25-pin RS-232 connector).

Therefore, you must have at least the RTS pin (pin 4) wired straight through on your RS-232 cable. The CTS pin (pin 5) is optional.

LookoutDirect initiates a serial transmission on an RTS/CTS port by first asserting RTS to key the radio. LookoutDirect then begins monitoring the state of the CTS pin. When the radio transmitter is fully keyed and ready to transmit, the radio asserts CTS and LookoutDirect immediately begins data transmission. If the radio does not assert CTS within the CTS timeout setting

(default is 100 ms), LookoutDirect assumes the radio is ready to transmit and transmits anyway.




The CTS timeout setting is the maximum amount of time that LookoutDirect waits after asserting RTS for CTS before transmitting. Most radios typically take between 10 and 80 milliseconds to key up. Consult your radio specifications and DIP switch settings to determine the key-up delay on your radio.

If your radio can assert CTS when it is ready to transmit, add about

50 milliseconds to the radio key-up delay specification and use this total value for the CTS timeout. If your radio does not assert CTS, you should begin by adding about 20 milliseconds to your radio key-up time. Then, increase this value in 10 millisecond increments until the remote radio begins to correctly receive the first bytes of the message.

Some radios might assert CTS before they are actually ready to transmit. In this case, disconnect the CTS line (pin 5 on a 25-pin RS-232 connector) and set the CTS timeout to a value high enough to let the radio fully key before transmission.

After it transmits the last byte of data, LookoutDirect continues to assert RTS, keeping the radio keyed until the RTS delay off time period expires. You should set this value to the default of zero milliseconds so that LookoutDirect unkeys the radio as soon as possible to prepare to receive the response.

When unkeyed, most radios generate an audible squelch tail that the remote device might decode as unexpected garbage bytes. Some remote devices reject the entire message instead of just decoding the valid data and ignoring the extra garbage bytes. In this case, keep the radio keyed for several milliseconds using the RTS delay off setting. This time period delays the squelch tail long enough for the remote device to recognize the last data frame as valid before receiving garbage bytes caused by the squelch tail.

If you set the RTS delay off setting too high, the remote device begins transmitting its response before the local radio is unkeyed, causing a communication alarm in LookoutDirect.

Dial-Up Modem Settings

Use the Dial-up serial connection when you use a modem in conjunction with a switched telephone line (not leased line). You can customize the dial-up settings for your particular modem and phone line.

The default Dialing prefix settings are based on the Hayes Corporation

AT command set, which is an industry standard for data modems. The following table explains the LookoutDirect default settings. For additional commands, refer to your modem operation documentation.



AT

D

En

Mn

Vn

Xn

Table 3-1. Dialing Prefix

Attention code that must precede all commands

Dial phone number with these modifiers:

P

for pulse;

T

for tone

Local echo mode:

E

for no echo

Speaker on or off:

M

for speaker always off

Verbal or numeric result codes:

V

for numeric result codes

Result code and dialing options:

X4

waits for dial tone before dialing, and recognizes busy signal


When you use an external dial-up modem with LookoutDirect, the DTR line in your cable between the modem and the computer must be wired straight through. This line is pin 20 on a 25-pin RS-232 connector and pin 4 on a 9-pin connector. LookoutDirect uses the DTR line to command the modem to disconnect (hang up) and return to the command mode.

Some factory modems are not configured to respond to the DTR line. After

LookoutDirect first successfully dials out to a remote modem and finishes the polling cycle, it drops the DTR line but the modem remains connected. If the modem does not respond after several seconds of LookoutDirect attempting to raise and drop the DTR line, LookoutDirect generates an alarm stating that the modem is not responding. If you receive this alarm message, your modem is not configured to monitor the DTR line.

The Hayes Corporation standard command for configuring the modem to hang up and enter command mode upon loss of DTR is

&D2

. You can use a terminal program to make this setting permanent on most modems by entering the modem command

AT&D2&W

to store the setting permanently in nonvolatile modem memory. Or you can just add

&D2

into the Dialing

prefix. The default Dialing prefix is

ATX4MVEDT

, so you might change it to

AT&D2X4MVEDT

.

Retries specifies the number of times LookoutDirect dials the specified phone number and attempts to connect to the modem at the other end of the line. If LookoutDirect fails to connect after the specified Retries, it generates an alarm and moves on to the next phone number in the polling queue (if a queue has formed).

Wait for connection specifies the length of time LookoutDirect waits to receive a connect signal back from the modem it is calling. The time period begins when LookoutDirect first sends the local modem the dialing prefix command. The time should be long enough for the local modem to receive a



dial tone, dial the phone number, allow the remote modem to pick up the line, and send back a connect message. If the specified time is too short, your system could be operating correctly but never make a connection.

Pause between calls is the length of time LookoutDirect waits after hanging up before it sends the local modem the next dialing prefix signal. If the specified time is too brief, your system might not hang up the existing call but still attempt to call the next number.

Note

Your specific modems, radios, and local phone lines might operate faster or slower than the default settings. You might need to use a trial-and-error approach to find the best settings for your system.

Serial Port Hangup

You can configure your serial port to use +++ATH hangup as well as DTR hangup.

Every serial port you have configured will have a configuration section in the

LookoutDirect

.INI

file under the port name, such as

[COM1]

. Add the following entry to the file to set your hangup mode:

DTR_Hangup=N

When

N

=1 (default), that port uses DTR hangup. When

N

=0, the port uses

+++ATH hangup.

Serial Port Diagnostics

You can create serial port diagnostic files to help solve serial port problems.

Open the LookoutDirect

.INI

file (located in your LookoutDirect directory) with a text processor. Every serial port you have configured has a configuration section in this file under the port name, such as [COM1]. Add the following entry to the file to create a diagnostic file

Diagnosticfile=N:\completepath\filename where

N

is the drive letter, followed by the complete path to the file (including the file name) you want to hold your diagnostic information. After editing the

Lookout

.INI

file, reload your LookoutDirect process file to force

LookoutDirect to reread the

.INI

file.





4

Networking

With LookoutDirect, you can monitor and control your process from any workstation (node) on the network.

LookoutDirect is designed to make networking easy. When you want to display an expression or make a connection from one process to another, you use the following dialog box, which appears in one form or another in many

LookoutDirect dialog boxes, as well as in the LookoutDirect Object Explorer.

Each computer registered as running LookoutDirect appears in this dialog box. Click on the computer to open the full display and reveal the processes currently running on that computer. Click on a particular process to reveal all the objects in that process that you can access.

After you navigate to the computer and process you want to make a connection to, you work as you would with any local LookoutDirect object.



Chapter 4 Networking

Registering Computers

Use the LookoutDirect Connection Browser or LookoutDirect Object

Explorer to register the computers running LookoutDirect processes on your network.

In addition to registering computers, both the Object Explorer and the

Connection Browser perform a number of useful functions in LookoutDirect.

These other functions are detailed in Chapter 3, LookoutDirect

Basics:Windows, Tools, and Files, of the Getting Started With LookoutDirect manual.

To register the computers using LookoutDirect on your network, open a process. Select Object»Connection Browser or Object»Object Explorer.

Right-click on

Network

, and select Register Network Computer. The following dialog box appears.


Type the name of the computer in the Computer name field. If you are unsure of the spelling, you can browse the network for computers by clicking on the network node in the Entire Network field.

To remove a computer from your list of registered computers, select

Object»Connection Browser or Object»Object Explorer and double-click on

Network

. Highlight the name of the computer you want to remove, and select Unregister Network Computer.



Logging Data

Before you can log data across the network, you must select the Log to

historical database option for the data member you want to log. Choose

Object»Edit Database to select this option. The dialog box you see might vary from the one shown here, depending on what object you edit the database for. For more information, refer to Chapter 3, Getting Started with

LookoutDirect in the LookoutDirect Getting Started Guide.

Time Synchronization

To keep your data properly time stamped, you must make sure the times on your computers are properly synchronized. The LookoutDirect time synchronization service is installed as a service in Windows NT that runs every time you run your computer. Time synchronization runs as a background process in Windows 98/95.

To configure time synchronization, select Options»Time Synchronization.

The following dialog box appears.




Any computer that is running the time synchronization service can serve as a time server or a time client. The primary time server is the first computer listed in the Time Server Search Order field.

Note

You must make sure that the order of search for time servers is the same for all the computers running LookoutDirect on your network, including the primary time synchronization server.

You do not include a computer running LookoutDirect in its own list of time synchronization services.

Suppose you have four computers you need to have synchronized. If one fails, the others look for the next in line to synchronize to as time servers. For computers A, B, C and D, you would use the following time server search order in each computer.

Computer A

None listed

Table 4-1. Time Synchronization Order

A

Computer B

A

B

Computer C

B

C

A

Computer D

As the primary time server, Computer A would have no other servers listed.

As long as Computer A is running, it should synchronize to itself. Computer

B should synchronize to Computer A as long as A is running. If A is not running, B should synchronize to itself. Computer C should synchronize to

Computer A if it is running, Computer B if A is not running, and to itself if neither A not B is running. This pattern should be used for all the computers you want in one synchronized set.



To change the order in which your computers search for a time synchronization server, select the computer name and click on the Up or

Down buttons.

Use Sleep Time (seconds) to set how long each computer waits between each synchronization. You should set the primary time synchronization server sleep time to 60 seconds.

If your primary server is off-line for some reason, a computer scheduled to synchronize automatically seeks out the second computer on the synchronization server list. At the time of the next synchronization, the computer first looks for the primary server before seeking a secondary synchronization server.

Note

If you have some computers running Windows 98/95 and other computers running

Windows NT in your network, you should list your Windows NT machines first in the server search list. Time synchronization works better between Windows 98/95 and Windows NT systems when the Windows NT computer is the server.

To add a computer to the Time Server Search Order field, click on the Add button. The following dialog box appears.


If you know the name of the computer you want to add, you can type it into the Computer name field. If you do not know the exact name of the computer, you can browse for it in the network tree contained in the second field.

To remove a computer from the Time Server Search Order field, highlight the computer name and click on the Remove button.



If no computer is set as a primary time server, your computer synchronizes to itself.

Checking the Network Connection between Two Computers

LookoutDirect networking, like the ping

program, is based on TCP/IP and assumes that computer network addresses can be resolved by name. Use the ping

program to see if two computers are properly networked before trying to run LookoutDirect.

Run ping

by opening a DOS window and entering ping server from the client and ping client from the server.

If you cannot successfully run ping from both computers, LookoutDirect networking will not work.

When ping runs successfully, it produces output similar to the following:

>ping plato

Pinging plato.natinst.com [123.45.67.89] with 32 bytes of data:

Reply from 123.45.67.89: bytes=32 time<10ms TTL=128




If ping

succeeds, but only after a long time, LookoutDirect will also take a long time to make connections.

One possible cause of a slow response is an incorrect domain suffix search order. Check this in your DNS configuration dialog box, and correct the search order if necessary. To access DNS configuration in Windows NT 4.0, select Start»Settings»Control Panel»Network»Protocols. Click on

TCP/IP Protocol to open the TCP/IP properties dialog box. Select the DNS tab to check the search order.

To access DNS configuration in Windows 98/95, select Start»Settings»

Control Panel»Network. Select the Configuration tab, and click on

TCP/IP in the list of installed components. The TCP/IP properties box appears. Select the DNS Configuration tab to check DNS search order.

Under Windows NT 4.0, open a DOS shell and enter the command nslookup computername



to see if DNS is working and to find out how long it takes to do the name lookup.

If ping

does not succeed, try accessing the Network Troubleshooter by selecting Start»Help»Troubleshooting. This Windows utility can sometimes diagnose a problem. In some cases, it might be necessary to use the machine’s fully qualified name, such as plato.dy.natinst.com

.

If the Network Troubleshooter does not resolve your problems, you might need to ask for help from a network administrator.





5

Dynamic Data Exchange


This chapter explains how to use Dynamic Data Exchange (DDE) with

LookoutDirect. DDE is the Microsoft message-based protocol used by applications like Microsoft Excel and LookoutDirect to link to data in other applications.

When the data in a source application changes, it dynamically updates all linked data (in real-time). With DDE, you can dynamically link other

Windows applications to LookoutDirect.

There are several DDE protocol formats. LookoutDirect supports the standard

Microsoft formats, XlTable and CF-TEXT. XlTable is often referred to as the

Fast table format; CF-TEXT is often called text format. LookoutDirect also supports hot DDE links and NetDDE.

Any two applications participating in dynamic data exchange are engaging in a DDE conversation. In such a conversation, LookoutDirect acts as either the client application or the server application (or both, in a peer-to-peer configuration). If LookoutDirect is getting data from another application,

LookoutDirect is the client. But if another application is getting data from

LookoutDirect, then LookoutDirect is the server.

The client application is responsible for establishing a DDE link with the server. When LookoutDirect is a client, it first tries to establish an XlTable

DDE connection (because this is the most efficient). If the server application does not support this format, LookoutDirect uses the CF-TEXT DDE format.

To establish a DDE link, the client application must identify the location of the desired data. A three-tier address identifies the location of the data:

Service, Topic, and Item. Look in the application documentation to determine its service, topic, and item.

Service specifies the name of the server application the client is linking to.

Each application that supports DDE has a unique service name. For example,

LookoutDirect is the service name of LookoutDirect, and

EXCEL

is the service name of Microsoft Excel.

Topic is the second level in the three-tier address. For many server applications like Excel and LookoutDirect, topic specifies a particular file.


Chapter 5 Dynamic Data Exchange

In LookoutDirect, the topic is the process file name, minus the

.LKP

extension. For example, you would refer to a process file named

PLANT.LKP

as

Plant

when using it as the topic in a DDE link.

Item identifies the specific data or value being linked between the server and the client. A LookoutDirect item is the object name, followed by a specific data member (such as

Name.datamember

) if needed. See Identifying Object

Data Members in Chapter 4, Using LookoutDirect, of your Getting Started

with LookoutDirect manual for detailed information on selecting objects and data members. An item in a spreadsheet, such as cell B3 in Microsoft Excel, would be r3c2.

Linking Lookout

Direct

to Other Applications

LookoutDirect can act as a DDE client, DDE server, and both DDE client and server. Therefore, there are three basic ways to link LookoutDirect to another application using DDE:

• LookoutDirect as the server

• LookoutDirect as the client

• LookoutDirect as both client and server (peer-to-peer)

Note

All readable numeric, logical, and text values in LookoutDirect are automatically available to any other application through DDE. No special setup is required.

Because Microsoft Excel is widely used and accepted, it is used in the

LookoutDirect DDE examples.

DDE Server Example

In this example, you can send information from LookoutDirect to another application, making LookoutDirect the server. First, create a potentiometer in

LookoutDirect so you can link its value in real-time to a cell in Excel. Any time the Pot is adjusted, the value in the spreadsheet cell automatically changes.

1.

Make sure LookoutDirect is not in edit mode.

2.

Hold down the <Ctrl> key and click on the object you want to link to. In this case, select the Pot object you just created.

3.

LookoutDirect beeps when it successfully copies the object value to the clipboard. The object can be a slider, bar graph, switch, pushbutton, digital display, text entry object, knob or almost anything else in

LookoutDirect that contains a value.

4.

Start Excel and select the cell you want to link to.



5.

If your version of Excel is 5.0 or later, select Edit»Paste Special, then click on Paste Link. If you have an older version of Excel, select

Edit»Paste Link.

You have just created your first DDE link. Repeat this process as many times as you need. If you are linking large numbers of objects to Excel, you might want to use the Excel copy and edit tools to speed up the process.

Not all applications support the Windows clipboard shortcut method as described above. Therefore, you might have to manually enter the appropriate

LookoutDirect service, topic, and item in the other application to create a

DDE link to that package. The format in which you enter this information varies from one package to another. For this reason, you should refer to the documentation of the client application for instructions.

DDE Client Example

In this example, you import information from another application into

LookoutDirect. For instance, you might want to use a value calculated inside a spreadsheet as a process control setpoint for a LookoutDirect application.

In this kind of DDE link, LookoutDirect is the client and the spreadsheet application is the server. Because LookoutDirect is the client, it is responsible for establishing the link to the server data. Therefore, you must identify the service, topic and item in LookoutDirect. These are object parameters in the

DdeLink object class.

1.

Select Object»Create and select the DdeLink object class.


2.

In Service, enter the name of the software package (

Excel

in this example).

3.

In Topic, enter the name of the spreadsheet file.

4.

In Item, enter the address of the cell you want to read a value from.

Notice that the entered cell address is r1c1

. This translates to row1/column1 (cell A1) in Excel. The Excel DDE structure requires this format.



5.

Click on OK, and then select OK again when LookoutDirect prompts you to insert the expression

DDE1

. Finally, pick the desired display format and click on OK.

To test your link, enter a numeric value into cell A1 of your spreadsheet.

Whatever value you enter into the spreadsheet is immediately written to the

DDE expression on your panel. You can also connect the DdeLink object you just created to other LookoutDirect objects. Refer to the DdeLink definition in the online help for more information.

Note

The DdeTable object is another way of linking data to LookoutDirect using DDE. This object class links large quantities of data though the more efficient XlTable format. Refer to the DdeTable definition in the online help for more information.

DDE Peer-to-Peer Example

Assume you want to take the LookoutDirect as a DDE server example one step farther. Suppose you want to adjust the Pot to change a value in Excel and also be able to enter a different value in Excel to adjust the Pot. That is, you want to send data both ways through a DDE link. You can easily create such two-way links for user-controlled objects (that is, Switches, Pots, and

Pushbuttons).

Select Object»Create and define a new Pot; or select Object»Modify and select the existing Pot object.


1.

Change Position source from Local to DDE.



2.

In Service, enter the name of the software package (in this case, Excel).

3.

In Topic, enter the name of the data file.

4.

In Item, enter the address of the cell you want to read a value from, such as r1c1 (for cell A1 in Excel).

5.

Click on OK to create or modify the definition of the object.

6.

If the object is new, insert its display member into the panel so you can test your link.

To test your link, enter a value into the spreadsheet cell you specified and watch the Pot. Then adjust the Pot and watch the spreadsheet cell. You should see the values within the two applications change in unison.

Note

If you link to a Pot object, the linked value is numeric, so you enter a numeric value into the spreadsheet cell. But if you link to a Switch or Pushbutton object, the linked value is logical. Linked logical values are shown in spreadsheet cells as true

or false

. To change the value of a logical value in a spreadsheet cell, enter true

or false

,

0

or

1

, or on or off

.

DDE Alarms

The following section explains alarms that might appear in the LookoutDirect alarm window.

Cannot establish DDE conversation with <service>, <topic>

This alarm occurs if a LookoutDirect client is unable to connect to the server corresponding to the given service and topic. The alarm also occurs if the server terminates the conversation (for example, if the server is shut down).

The alarm is deactivated when the LookoutDirect client successfully connects to an item on the server.

Verify that the service and topic were typed correctly when you created the object that is using DDE. Verify that the server application is running. If the server is on another computer on the network, verify that the network is up.

If the server is on a computer running Windows NT, verify that you are authorized to log on to that computer and that the current user logged onto the

NT machine has trusted the DDE share to which you are trying to connect.

For more information, refer to the section Adding a Trusted DDE Share in

Appendix A, Networking With DDE.

DDE client error for <service>, <topic>, <item>: (received NACK for advise)




DDE client error for <service>, <topic>, <item>: (received NACK for request)

Verify that the named item exists on the server and that the server supports

DDE links for the item. This alarm occurs when LookoutDirect is a client.

DDE client error for <service>, <topic>, <item>: (received NACK for poke)

This alarm occurs if you are using LookoutDirect as both client and server, and have made a remote connection to an item that is not writable in a

DataTable, Pushbutton, Pot, Switch, or TextEntry. The only LookoutDirect objects that support writes (pokes) are DataTable, PushButton, Pot, Switch, and TextEntry. These support writes into their implicit data members only.

If the server is running Windows NT, it is possible that the DDE share on the computer is configured to support reads (advises) but not writes (pokes).

DDE client error for <service>, <topic>, <item>: (advise timed out)

DDE client error for <service>, <topic>, <item>: (request timed out)

DDE client error for <service>, <topic>, <item>: (poke timed out)

Verify that the server application is running. Verify that the item exists on the server. If the server is on another computer on the network, verify that the network is up.

DDE client error for <service>, <topic>, <item>: (received invalid data)

DDE server: corrupt data block poked to item <item>, topic <topic>

Either the server received a corrupt data block from the client, or the client received a corrupt data block from the server. This might be the result of network trouble. If the alarm is consistent and predictable, you might have discovered a bug. Call National Instruments technical support for further help.

DDE server: failed to post advise for item <item>, topic <topic>

Verify that the client application is running. Verify that the item still exists on the client. If the client is on another computer on the network, verify that the network is up.


6

Security


This chapter describes the two types of LookoutDirect operational security: network security and control security. Viewing security is primarily based in control security. You can use either or both security approaches to control who has access to different processes, control panels, individual controls, and data.

LookoutDirect processes can pass data and commands back and forth across a network. LookoutDirect security prevents or enables this communication based on who is logged in on each instance of LookoutDirect running on the networked computers. LookoutDirect network security works between different instances of LookoutDirect running on one computer or different computers on the same network.

Network security is based on user and group permissions configured for processes, collections of objects grouped in a folder, or individual objects.

Control security is based on security level parameters set in a given

LookoutDirect object, usually a control such as a Pot or Switch. This security level is compared to the security level assigned to a user account or a group to prevent or enable access.

A user account identifies a single person authorized to log on to

LookoutDirect. Groups consist of collections of users with similar duties and security levels.

Security information for a LookoutDirect process is kept in the

.lka

file for that process. You must keep the

.lka

file in the same directory as the

.l4p

file for your security settings to work. If you misplace the

.lka

file, all users will have complete access to all parts of the process.

The user and group account information for LookoutDirect 4 is kept in the

Lookout

.sec

file, installed in your Windows

SYSTEM

directory.

If you want basic authentication to work between different computers running

LookoutDirect on your network, you must have an identical

Lookout

.sec file installed on each computer. You can do this by creating a master security file on your main development computer and copying it to all the other computers running LookoutDirect on your network.


Chapter 6 Security

To preserve user and group account information from versions of

LookoutDirect prior to LookoutDirect 4.0, import the old security file into your new security file using the Import LookoutDirect 3.x Security File option in the LookoutDirect User Manger. See the Importing Old Security

Files into LookoutDirect 4 section for more information on importing old security files.

Permissions and security levels are cumulative in LookoutDirect. If you add a user account to a group that has a group security level or permissions different than that assigned to the user account, the user will have the higher of the two security levels or permissions.

Note

While it is possible to assign a security level to a user account and then put that user into a group with higher (or lower) security levels, it is not a good practice. To minimize confusion, it is best to assign user accounts to groups with the same security level when possible. Refer to the Keeping Security Precedence Simple section of this chapter for information on how different security levels and group permissions interact.

Logging On

LookoutDirect requires operators to log on with a predefined name and corresponding password (if any). To log on, use the File»Log on command, press <Ctrl-L>, or click on the Account name box in the status bar.

Collectively, the name and password are known as a user account, or account.

Each account has a security level and can be included as a member of a group.

Because LookoutDirect uses account names when logging events to disk and when operators acknowledge alarms, you can identify the operator logged on when an event occurs.

You can programmatically access the name and security level of the currently logged LookoutDirect user through the $System object, using the username and seclevel

data members.

All users must log on to LookoutDirect. When nobody has logged on to

LookoutDirect, LookoutDirect shows (nobody) as being logged on in the status bar at the bottom of the main screen. The (nobody) account is built into

LookoutDirect with a security level of 0 (zero), and cannot be edited.

Note

If the (nobody) account is logged on, any functions of client or server processes running that require a security level greater than zero do not receive or report data until someone logs on using an account with a high enough security level.

The first time you start a development version of LookoutDirect, the

Administrator user account has no password. Any time the Administrator



account has no password, LookoutDirect opens with Administrator logged in and active, without requiring any login. This is a convenience for you when creating your LookoutDirect processes, but you must be sure to assign a password to the Administrator account before allowing others who should not have Administrator privileges to use your copy of LookoutDirect.

Note

Server and client run-time versions of LookoutDirect open with the (nobody) user account logged in, no matter what the password setting for the Administrator account.

After you have added a password to the Administrator account using the

LookoutDirect User Manager, development versions of LookoutDirect open by presenting the Welcome to LookoutDirect dialog box which requires a

LookoutDirect user to log in.

Each time you log on, enter your User name and Password.

Note

If yours is the only account that is a member of the Administrators group, and you forget your password, there is no way to access the System»User Manger command, and there is no way to modify account settings. Contact National Instruments for assistance.

Domain—In current versions of LookoutDirect, you can only log on to your local domain.

Idle time—The amount of time the computer sits idle (no mouse movement or keyboard action) before LookoutDirect automatically logs off the operator.

If you enter

0

(zero), idle time is disabled. For security reasons, you might want to use this feature to automatically log off high-level accounts if the computer is left unattended too long. After an account logs off, the account

(nobody)

is logged on. The

(nobody)

account has a security level of 0

(zero).

By default, LookoutDirect presents you with the login dialog box every time you open the program. To log off, select File»Log off or press <Ctrl-D>. No dialog box appears in response to either of these actions; LookoutDirect just logs you off. You can also log off though the login dialog box.




To log on after LookoutDirect has automatically logged you out, after someone else has logged off, or just to log in and replace the current user, select File»Log on or press <Ctrl-L> on the keyboard.

User Manager

You create individual accounts for operators and developers with the User

Manager. Anyone whose account is a member of the Administrators group can create, revise, or delete system user accounts by selecting Options»User

Manager. The LookoutDirect User Manager dialog box appears, as shown in the following illustration.

Note

For your user accounts to work consistently across your network, you must use the same

Lookout

.sec

file for all your installed copies of LookoutDirect. After you have created your Lookout

.sec

file, make a copy of it from your

WINDOWS\SYSTEM

directory.

Place a copy of the file in the

WINDOWS\SYSTEM

directory of each of your LookoutDirect computers.

You should carefully consider users and the security level you assign each one. Assign level 10 access only to those people responsible for system security. Users with security levels of 8 and higher can close process files and exit LookoutDirect. Users with security level 9 or higher can edit process files in development versions of LookoutDirect.


From this dialog box, you can create and edit the properties of groups, create or edit the properties of user accounts, assign users to one or more groups, and otherwise manage security in LookoutDirect.



Creating User Accounts

To create a user account, select User»New User. The following dialog box appears.


Enter the new user’s domain name in the Username field.

Enter the user’s Full Name.

You can use the Description field for job titles or other relevant information.

Enter the user’s password in the Password field.

Enter the password a second time in the Confirm Password field to make sure there was no typing error in the first entry.

Set the new user’s Security Level. LookoutDirect security levels range from

0 to 10, with 10 being the highest possible security authorization. Assign level

10 access only to those people responsible for system security. Users with security levels of 8 and higher can close process files and exit LookoutDirect.

Users with security level 9 or higher can edit process files in development versions of LookoutDirect.

Select the Account Disabled checkbox if you want to disable a user account without removing the user from the system.

Click on the Groups button to add this user to various local security groups.




The default groups in LookoutDirect are Administrators, Guests, Operators,

System Operators, and Everyone. Any groups you have created are also shown.

To enter a user in a group, highlight the group in the Not Member of field and click on the Add button. To remove a a user from membership in a group, highlight a group in the Member of field and click on the Remove button.

Note

When you add an individual user who has a security level different than that of the group, that user will have the higher of the security levels.

Creating Groups

To create a group, select User»New Local Group. The following dialog box appears.


Group Name assigns a name to your new group.

Enter a description of the group in the Description field.

Security Level assigns the security level for members of this group.



Note

When you add an individual user whose individual account has a security level different than that of the group, that user will have the higher of the two security levels.

To add Members, click on the Add button. The following dialog box appears.

The List Names From listbox selects the domain to list user names from. In this version of LookoutDirect, you are restricted to your local domain.

Highlight the names you want to add in the Names field, and click on the Add button to add those users to your group.

Modifying Users and Groups

The dialog boxes for editing users and groups are essentially the same as those for creating users and groups. Open the User Manger, right-click on the user or group you want to edit, and select Properties. The following dialog box appears.




The User Properties dialog box displays information about user activity.

Special Users and Groups

LookoutDirect comes with several users accounts and groups built-in. The user accounts include Administrator, Guest, and (nobody). The built-in groups include Administrators, Everyone, Guests, Operators, and System

Operators. You cannot delete any of these accounts, though you can edit the properties of some of them.

The Administrator account overrides all other security settings and has access to everything in LookoutDirect. This override extends to all accounts added to the Administrators group.

You cannot delete the Administrator account or change its security level. You can set the password and enter the name and a description of the

Administrator. You can also add or remove user accounts.

The (nobody) account cannot be edited or deleted. This account is what

LookoutDirect defaults to when no authorized user is logged on. It always has a security level of 0.

The Everyone group is built into LookoutDirect. You cannot edit or delete this group in the User Manager. When you first create a process in

LookoutDirect, it is configured with this group allowed full read and write permissions. Because objects inherit their permission status from the process or folder in which they are created, all the objects you create have this same status until you change them manually, or change the permission status of the process or folder you create them in.

You can edit all the properties of the Guest user account and of the Guests,

Operators, and System Operators groups.



Control Security

Several object classes in LookoutDirect support control security, including such control objects as the Pot, Switch, Pushbutton, RadioButtons, and

TextEntry, along with a few driver objects. Each class provides some type of control—Pots control numeric output signals, and Switches and Pushbuttons control logical output signals. Each class accepts the control security level parameter, which determines whether an operator can control the object.

Refer to the online PDF LookoutDirect Object Reference Manual for additional information about control object properties.

With control security, LookoutDirect compares the security level control of an object to the security level of the currently logged-on account (the operator) to determine if an operator can control (write to) a particular object.

With network security, LookoutDirect checks the user account permissions configured for an object or process to determine if an operator can control

(write to) a particular object. The user can adjust a control, but the process does not accept the input and the control will return to its original value.

Under control security, if the account security level is equal to or higher than that of the object, the mouse cursor changes into a hand when positioned over the object and the operator can adjust and control the object.

Control Access Is Denied

Control Is Accessible


If the account security level is lower than that of the object, the cursor changes into the international symbol for forbidden, and the operator cannot control the object.

You can implement this feature on an object-by-object basis, either through the individual security level set in the object properties dialog box, or by assigning permissions. System integrators can secure high priority Switches,



Pots, and Pushbuttons from operators while still allowing operators to adjust lower-level security objects. Refer to the Configuring Security for Processes

and Objects section for more information on assigning permissions.

LookoutDirect globally applies the Control Panel object security setting to all individual objects on that panel and assigns the higher security level

(either the control panel or the individual object) when determining whether an operator can access an object. Refer to the discussion of the Panel object in the online PDF LookoutDirect Object Reference Manual or the online help for additional information.

Viewing Security

LookoutDirect provides viewing security for control panels, controllable objects, and system settings. With these security options, you can restrict access to control panels, objects, and Windows system resources.

Control Panels

A Control Panel object defines viewing security for the entire control panel.

For example, if you set Viewing security to level 6 on a particular panel, operators with level 5 or lower cannot view that control panel and might not even know that panel exists. If a level 6 (or higher) operator logs on, the control panel instantly becomes available for display. This feature is useful for hiding panels that are rarely used or that contain sensitive information.

Controllable Objects

Controllable objects such as Pots, Switches, Pushbuttons, and so on have a writable data member called visible

. When visible

is true, you can see the object on a control panel. When visible

is false, you cannot see or adjust the object. To ensure that the object is always visible when it is first created, visible

defaults to true.

You can connect the visible

data member of a controllable object (for example, a Pot object) to a controller mode indicator. When the controller is in computer control mode, the visible

data member of the Pot might be true, allowing the operator to see the Pot and adjust the setpoint. But when the controller is not in computer control mode, the visible

data member might be false, hiding the Pot from the operator and prohibiting operator control.

You can also use the username

or seclevel

data members of the $System object to control the visibility of a control object, depending on the name or security of the person logged on to LookoutDirect at any given time.



You can also configure network security permissions on these data members.

System Security Settings

With the Options»System menu command, you can define system options in the System Options dialog box to keep LookoutDirect maximized, the menu bar invisible, title bars invisible, and pop-ups to a minimum.


LookoutDirect will always be maximized—When you enter a security level, LookoutDirect prohibits users below that security level from closing

LookoutDirect.

Users cannot switch to another program—This prevents an operator from using <Alt-Tab> to switch from LookoutDirect to some other program running on the computer. For this feature to work properly under

Windows NT, you must install the LookoutDirect NT keyboard driver when you install LookoutDirect.

Menu bar (and title bars) will not be visible—When you enter a security level, users below that security level cannot view the menu bar or the title bar and, therefore, cannot change to a different Windows application.

This feature is not completely supported under Windows NT 4.0. With

Windows NT 4.0, you can still use <Ctrl-Esc> or the Windows key to activate the Windows Start menu or <Ctrl-Alt-Delete> to bring up the Task Manager.

Limit active popups to—This option requires two values: a security level and the number of pop-ups. Users below that security level can view up to the



specified number of pop-ups at one time. This feature keeps new users from becoming lost.

Network Security

LookoutDirect development security is modeled after Windows NT security but is supported for LookoutDirect processes running on Windows 98/95 as well. Users with the ability to access processes or elements within a process are organized into groups. You can limit group and user access to processes, folders, and objects.

Configuring Security for Processes and Objects

You can control access privileges by user or group, applying restrictions to processes, folders within a process, or individual objects. You can configure security in the tree views contained in the LookoutDirect Object Explorer, the

LookoutDirect Connection Browser, the Edit Connections dialog box, or the

Insert Expression dialog box.

You cannot configure security for a network node, for your local computer, or for any LookoutDirect global objects such as $Keyboard or $System. You must select a process, a folder within a process, or an object within a process or process folder to configure security.

Right-click on the process or object you want to configure security for and select Configure Security. The Security Properties dialog box appears.


From this box, you can either set Permissions, or do Advanced security configuration by clicking on the appropriate button.

Permissions

With permissions, you can set individual access privileges for a given process, a folder holding a collection of objects, or individual objects.



Configure security permissions using either the LookoutDirect Object

Explorer or the LookoutDirect Connection Browser.

LookoutDirect objects inherit the permission status of the process or folder in which they are created. When you first create a process in LookoutDirect, it has full read and write permission granted to the Everyone group, by default.

Any folder or object you create in the process has the same permission.

If you change the permission of the process or of one of the folders, any objects you create after the change have the permission status of the parent process or folder. Changing the permissions of a process or folder does not always change the permissions of an object or folder that already exists in that process, depending on how you set the Permissions dialog box options.

If a process has one set of permissions, and a folder under that process has a different set, the objects created under the folder will inherit the permission status of the folder only.

Select Permission from the Security Properties dialog box. The

Permissions security properties dialog box appears.


The dialog box in the illustration above shows everyone with access to

LookoutDirect having permission both to read and write all the controls in the

Reset_Panel

folder of the

Server_1

process.

Your options are to substitute individual users or groups for the Everyone group, and give each user or group the appropriate permission. You can refuse access, permit reading or writing only, or allow both reading and writing.



Note

Remember that permissions in LookoutDirect are cumulative. For your individual user and group permissions to have any effect, you must delete the Everyone group after you set your other permissions. Refer to the Special Users and Groups section for more information on the Everyone group.

Select the user or group you want to assign permissions for. Select the appropriate security level in the Type of Object Access list in the lower right section of the dialog box. When you are done, select OK.

By selecting or disabling Replacing Permissions on Subfolders and

Replacing Permissions on Existing Objects, you can restrict that permission to the process, folder, or object you selected, or extend the permission application in different ways and to different degrees.

In the simplest case, if you have selected an individual object, you can only change the permissions on that object.

If you selected a process or folder, the options function as shown in the following table.

Replacing permissions on subfolders

Replacing permissions on existing objects

both

Table 6-1. Options for Propagating Changes in Security through a Process

Options Selected

neither

Result

Only the selected process, folder, or object has its security configuration changed.

Changes permissions on the selected process or folder, all the folders under it, and any subfolders under them.

This option is disabled when an individual object is selected.

Changes permissions on all the individual objects contained immediately under the selected process or folder, but does not change permissions on any folder or subfolder, or any object in them.

This option is disabled when an individual object is selected.

Changes permissions on all the individual objects contained immediately under the selected process or folder, as well as on any folder or subfolder, and all the objects in them.

To remove a user or group entirely from the permissions list, select the user or group and click on the Remove button.

To add a user or group, click on the Add button. The following dialog box appears.



Select a user or group account in the top window and click on the Add button.

Click on OK when you have selected all the users and groups you want to add.

Configure the security permissions for the added groups as described in the beginning of this section.

Advanced Security

You can set a number of advanced network security options in

LookoutDirect, but only at the process level. These options are not available on the folder or object level. Click on the Advanced button in the Security

Properties dialog box. The Advanced security properties dialog box appears.


There are three advanced security options: Basic authentication, IP setting, and Proxy user.

The default LookoutDirect setting is to have both Proxy user and Basic

authentication enabled and the other option turned off.



As with other LookoutDirect security settings, the effects of multiple selections in this dialog box are cumulative. In other words, if a user had permission to read under Basic authentication and to write under Proxy

user, then if both options are enabled the user would be able both to read and write.

Basic Authentication

When you select this option, LookoutDirect checks the account information of a user logging in to that instance of LookoutDirect. Security responds to the security level, individual account, and group permissions of that user account.

At this time, LookoutDirect cannot process the security status of a person logged on to another computer unless you install an identical

Lookout

.sec

file on each computer running LookoutDirect on your network. Otherwise, if you have base authentication but not proxy access active on a server process, a person attempting to read from or write to a server from a remote computer cannot access the process unless you have configured the permissions for the

Everyone group to have such access.

Activating the proxy access option in addition to the basic authentication option greatly increases your security options.

IP Setting

You can configure LookoutDirect to grant or deny access to any computer operating at a specific IP address. Click on the IP setting checkbox to enable this feature.

To grant or deny access by IP address, click on the IP setting button. The IP

Setting dialog box appears.



Only one of the IP setting options can be active at one time. Select whether you want to grant access or deny access to a given set of computers.

Note

The IP access option functions in a literal way. If you choose to grant access to one or more computers using the IP setting option, those will be the only computers able to access the process or object you have applied the restriction to. If you choose to deny access to one or more computers using the IP setting option, all other computers using LookoutDirect will be allowed to access the process or object you have applied the restriction to, subject to the other security settings in place.

Enter the IP address you want to add, and click on the Add button. You can enter either the IP number itself, or the simple name of the computer. Whether you use the IP number or the simple computer name, the IP address for the computer appears in the list after you accept the entry.

Proxy Access

You can, if you choose, designate a specific local security account whose security level applies for any user accessing processes in your local instance of LookoutDirect from another computer (or another instance of

LookoutDirect running on the local computer).

In other words, no matter who is logged on to another instance of

LookoutDirect, the proxy account determines external access rights to a process or object operating under this option. The security level of the operator logged into the external instance of LookoutDirect is ignored.

The Guest user is built into LookoutDirect, specifically provided for this purpose, as well as for providing a visitor with a user account. You can edit the Guest user account properties in the User Manager.




To enable the proxy option, select the Proxy checkbox. Enter the Username of the account you want to serve as the proxy security account.

You must enter the valid Password for the user account for the proxy option to function.

When a user attempts to access your LookoutDirect process or objects from another domain, the user’s logon is recorded in the LookoutDirect events database. The user will be restricted to the security levels you have configured locally. You must configure any further access restrictions in the client process.

Keeping Security Precedence Simple

The LookoutDirect security system is flexible and designed for compatibility both with earlier versions of LookoutDirect and with planned future versions.

This flexibility carries with it the risk of complexity.

It is not necessary to use every security feature in every LookoutDirect process. Keeping your security as simple as possible is the best approach. The following suggestions should help you keep your security simple.

• When converting a LookoutDirect process from LookoutDirect 3.8.xx or earlier, leave the control security in place when possible.

• In cases when you have both security parameters and network permissions set for an object, it is best to make sure that the security level parameters are consistent with permissions.

If you do find yourself with complex security setting interactions, the following principles should help you sort out how your interactions will work.

• User and group permissions are cumulative.

For example, if user_A is a member of both Operators and System

Operators, with the Operators group having read access and the System

Operators group having Write access, user_A has both Read and Write access.

• Permissions and control parameter settings are cumulative.

For example, if a control object has a security parameter set to 7, and user_A’s user account has a security level of 5, user_A cannot access the control. But if user_A is also a member of the Operators group, and the

Operators group has a security level of 7, user_A can access the control.

Additionally, if a control object has a security parameter set to 7, and user_A’s user account has a security level of 5, user_A will nevertheless



have read permission if you use network security to grant read permission to user_A’s user account.

• The no access setting overrides all other permissions granted to a user or the user’s group.

For example, if user_A is granted a read access, and user_A is member of Operators, if the Operators group has been assigned no access, user_A has no access either.

Additionally, if user_A is a member of both Operators and System

Operators, and Operators group has been assigned no access, user_A has no access either—even if the System Operators group has read access.

Process File Edit Security

You can protect your process files from being edited by any other person without using the security accounts. Log in with an account name and a non-empty password, and select File»Save As from the menu. The following dialog box appears.

Check the Protect file from editing with your account name/password box at the bottom of the dialog box to save the file with your password as protection. To edit the file again, you have to log in under the same account with the same password.

Note

You cannot open an encrypted file with an earlier version of LookoutDirect, even if you create an account with the same account name and password in that version.




Caution

When you protect a process file, LookoutDirect does not save the

.LKS

file.

Because the

.LKS

file serves as a backup file during application development, you should not use the encrypted-save feature until after you have completed your application and made a backup copy of both the

.LKP

and

.LKS

files on a separate archive disk.

Action Verification

The Switch and Pushbutton object classes support action verification. When you define action verification for an object, LookoutDirect displays a message box stating your Verify message and prompts you to select either Yes or Cancel. If you click on Yes, LookoutDirect completes the previous operator command (for example, flips the switch or presses the pushbutton). If you Cancel, LookoutDirect ignores the previous operator command.

All action verification parameters accept text expressions, which can contain dynamic data. As an example, consider a switch that controls a pump responsible for filling a storage tank. However, that pump should not fill the tank if the water level is too high. You might enter an expression similar to the following for the switch Verify On parameter:

“Are you sure you want to turn on sludge return pump #2?

Holding tank #2 is currently ” & DATA_VARIABLE & “ percent full.”

Refer to Chapter 1, Expressions, for more information about creating expressions using variables.

The warning message appears every time you turn on the switch. Notice the water level is dynamic—it changes to reflect the value of

DATA_VARIABLE

when the switch is flipped.

When you turn off the switch, no warning message appears because the

Verify Off parameter was not specified. If you want to disable the Verify On warning message, delete the entire expression from the data field.

Caution

Pushbutton verification works in much the same way. However, when you select

Yes, the pushbutton creates only a momentary output signal. When action verification is enabled, it is impossible to hold the button down for any length of time.



Importing Old Security Files into Lookout

Direct

4

You can import the user account information from your LookoutDirect 3.8 processes into LookoutDirect 4 using the LookoutDirect User Manager.

1.

Select Options»User Manager from the LookoutDirect menu. You must be in edit mode for the User Manager item to appear in the

Options menu. The User Manager dialog box appears.

2.

Select User»Import LookoutDirect 3.x Security File from the User

Manager dialog box. The following dialog box appears.


3.

Navigate to your old LookoutDirect 3.8 security file

Lookout

.sec

, and select it. LookoutDirect 3.8 kept the Lookout

.sec

security file in the

LookoutDirect directory.



4.

Click on Open.

5.

If you have already created any user accounts in LookoutDirect 4 that are the same as accounts you used in LookoutDirect 3.8, you will receive a message informing you that a user account with that name already exists.

You may replace your recently created account, or choose not to use the old account information.

6.

Exit the User Manager.

Note

Unlike LookoutDirect 3.8, LookoutDirect 4 maintains the Lookout

.sec

security file in the Windows

System

directory. The LookoutDirect 4 User Manager creates a unique identification number for each user account. For Basic Authentication to work properly, you must use the same Lookout

.sec

file for each copy of LookoutDirect running on your network. Copy your

Lookout

.sec

file to the Windows

System

directory in every computer on which you intend to run LookoutDirect.


7

Logging Data and Events

This chapter describes three LookoutDirect methods for logging real-time system data to disk—Spreadsheet Logger, Citadel Historical Database, and

Event Logger—and report generation.

The Spreadsheet Logger creates standard ASCII text files in comma separated value (

.CSV

) file format. You can open and edit these files with common spreadsheet and database programs. The Citadel Historical Database creates a historical database that LookoutDirect HyperTrend objects access in real time. You can retrieve this data using Structured Query Language (SQL). The

Event Logger creates a chronological audit trail of who did what and when.

You might implement all three methods on a single system. They are not mutually exclusive.

Refer to Chapter 9, Alarms and Events, for more information on the Alarm

Logger, which logs alarms to disk.

Note

When your operating system switches in or out of Daylight Savings time,

LookoutDirect corrects for the change relative to universal time so that there is no data discontinuity or loss in the Citadel database.

Spreadsheet Logger

When you want to create permanent ASCII files that you can later open with software packages such as Excel, Lotus, and Foxpro, use a Spreadsheet object to store real-time system data to disk.

You can generate more than one spreadsheet for a single process if you use multiple Spreadsheet objects in one process file (a

.LKP

file). You can have different spreadsheet files in different subdirectories and each might have different data stored using different logging criteria. For more information on the Spreadsheet object, refer to the Spreadsheet Logger description in the online PDF Object Reference Manual or online help.

The following illustration shows the create object dialog box that you use to configure a spreadsheet object.



Chapter 7 Logging Data and Events

Data Location

LookoutDirect stores spreadsheet files in subdirectories specified by the

Citadel Database section of the System Options dialog box illustrated below.

Developer’s Manual 7-2w ww.Automationdirect.com

CSV Files


All LookoutDirect spreadsheet files use the comma-separated value (

.CSV

) format. A

.CSV

file contains text separated by commas. Each line of the file represents a row of spreadsheet data. The first row lists signal names and describes the data stored in each column of the file. The first column of the spreadsheet file specifies the date and time data in each row was logged. The following illustration shows a

Lookout

.CSV

file opened by Excel.

You can view and edit spreadsheet files using a standard word processing program, but spreadsheet programs such as Microsoft Excel provide a more intuitive interface for viewing or editing data and printing custom reports.

File and Disk Errors

If LookoutDirect cannot find the data directory or spreadsheet files or cannot log data to disk, it generates a priority eight alarm with a descriptive error message. For example, if your default data location was on c:\lookout\database

, and LookoutDirect was to encounter a full disk while writing to a file named data.CSV

, the alarm text would read

(Disk is full) “c:\lookout\database\data.csv”.

When you correct the problem that caused the alarm, the alarm automatically resets.




Concurrent File Access

When logging data, LookoutDirect opens the file long enough to add a new row of data and then closes the file. LookoutDirect can log approximately ten new rows of data per second. (The time stamps associated with each row are rounded to the nearest second.) Because LookoutDirect runs under the

Windows multitasking environment, you can open the spreadsheet or database while LookoutDirect is running. If you have the data file open in a spreadsheet program such as Excel, LookoutDirect cannot add new rows of data to the file. If LookoutDirect does not have write access to the file, it generates an alarm explaining the problem.

Error writing spreadsheet file: Permission denied

[c:\lookout\database\data.csv]

If LookoutDirect cannot log data to the spreadsheet file, it creates a temporary buffer in memory to which it logs all the spreadsheet data. When you close the spreadsheet file, LookoutDirect updates it and resets the alarm.

Information Overload

If you create a Spreadsheet object that logs fifty data fields (object data members and/or expressions) at five-minute intervals, you generate

14,400 data points per day, or 432,000 data points per month. It can be difficult to determine which data are critical information.

Note

Carefully consider the importance of each data point and the time interval between data points to avoid information overload for both you and your spreadsheet program.

If you have logged more than 16,384 rows of data, the current version of

Excel cannot load the entire spreadsheet file. Spreadsheets created with one-minute intervals generate 44,641 rows of data if the directory tree location is set to Monthly. Spreadsheets created with two-minute intervals generate 22,321 rows of data if the directory tree location is set to Monthly.

To decrease the number of data rows, try changing the directory tree location to Daily, which generates only 1,440 rows of data per day at one-minute logging intervals. You can also use a text editor to divide the larger file into smaller files with fewer data rows.

Besides limiting rows to 16,384, Excel limits spreadsheets to 256 columns of data. One column is reserved for the date and time.



Citadel Historical Database

When you need to view historical information using LookoutDirect

HyperTrend objects or access historical data using Structured Query

Language (SQL), use the Citadel Historical Database to store real-time numeric and logical data in a compressed format.

LookoutDirect logs data only when the value of a point changes, not at a timed interval. The logged data accurately reflects the actual behavior of the point being logged because the same value of a point is not recorded over and over. With Citadel, disk usage is exactly proportional to the amount of information recorded.

After the data is stored to disk, you can view it with a HyperTrend object in LookoutDirect or with SQL. HyperTrend objects serve as windows into your database. SQL, an industry-standard language supported by most database packages, enables other applications to directly retrieve data from

Citadel.

Because Citadel uses Universal Coordinated Time (UCT) to time stamp the data, you do not need to compensate for data logged in different time zones.

The HyperTrend object automatically converts from universal to local time before displaying a data history.

Default Data Location

The Citadel Database fields in the System Options dialog box specify the root directory under which all data logging is stored, including the database. Ordinarily, Citadel creates a special database subdirectory in the

LookoutDirect directory. This subdirectory holds your historical database files.




If you move or rename the subdirectory or files, you will be unable to access your data. If you change the default directory, the change does not take effect until you stop and restart LookoutDirect. This also interrupts data continuity, and you have to do separate SQL queries to both databases.

Unlike spreadsheet files, only one historical database per LookoutDirect process exists. If you want to develop multiple processes where each process file has its own unique historical database on a single computer, specify a different location for each process database, as explained in the Process Data

Location section of this chapter.

Process Data Location

When you create a process in LookoutDirect, you have an opportunity to set the default data location for that process in the Create Process dialog box.



When this dialog box first appears, the Use default values checkbox is selected. This option directs LookoutDirect to log data from this process to the default location set in the System Options dialog box for the copy of

LookoutDirect running the process. In this way, you can create a process that logs to the default data location of any copy of LookoutDirect running on any computer you move the process to.

You can also direct data to a location on a remote computer, as long as that computer is running the LookoutDirect Citadel service. Deselect the Use

default values option and enter the computer and path you want data logged to.

Although you can direct data from different processes to different database directories, proliferating a variety of databases with large numbers of processes running in one instance of LookoutDirect can degrade performance, depending on the number of data points being logged.

Creating a Historical Database

Citadel stores historical information using traces. Trace refers to the line of continuity for a specific data member name or point. A trace connects all the historical values for a given point, which displays as a continuous line in a

HyperTrend object. If LookoutDirect is unexpectedly interrupted or a data member is temporarily modified to not log to disk, a trace can be broken. If the trace is broken, the HyperTrend plots the trace as a continuous line with void sections to represent gaps in the data. You cannot remove individual




traces from the database, but you can add new traces to the database by configuring a new point.

You can log any numeric or logical data member of any object to the historical database. Use the following procedure to add a trace to the Citadel database:

1.

Select Object»Edit Database and an object that contains data you want to log. A dialog box similar to the following appears.


2.

Identify the value you want to log in the Member data field. If the value was previously configured, select it from the Configured points list.

3.

Check the Log to historical database checkbox and choose an appropriate Lifespan. See Logging Criteria for an explanation of time span settings.

4.

Enter a value in the Deviation field. See Logging Criteria for an explanation of Deviation settings.

5.

Click on the Save or Update button. (If you are modifying an existing configured point, the button automatically changes to Update.)

6.

Configure all the object data members that you want logged to the

Citadel database.

7.

Click on the Select object button and select the next object containing data you want to log.

8.

Repeat steps 2 through 6 until you have created the traces that you need.

9.

Click on Quit.

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Logging Criteria

To create a new trace in the Citadel historical database, LookoutDirect needs the following information: data member name (Alias), Deviation, and Lifespan.

• Data member name (Alias)—LookouDirectt must name each trace in the historical database for archiving and retrieval purposes. If Alias is not specified, LookoutDirect uses the native data member name as displayed in the Member field. If an alias is assigned to the native data member,

LookoutDirect uses the Alias name instead. The name used for the trace is the same name saved to the Configured points list box.

• Deviation—If an analog value surpasses or equals the Deviation setting,

LookoutDirect saves a new value to disk in the database. If you implement Scaling parameters, LookoutDirect compares the Deviation setting to changes in the Eng. units values to determine when to log a new point. If you leave the Scaling parameters blank, LookoutDirect compares the Deviation setting to the raw (unscaled) signal. The

Deviation parameter is not available on logical signals because

LookoutDirect logs all state transitions of logical values to disk.

• Lifespan—LookoutDirect needs to know how long you want to maintain this trace of data in the historical database. LookoutDirect maintains the data for at least the time span specified in the Log to

historical database parameters.

LookoutDirect does not discard old data immediately. Disk space containing old data is reused when new data is logged.

Alarm Information Overload

Because LookoutDirect creates and maintains the historical database in 1 MB chunks, you must have a least 1 MB of available disk space to begin logging data. When the first 1 MB file fills up with data, LookoutDirect creates a second 1 MB file in the same directory. When the second fills up,

LookoutDirect continues to create 1 MB files until all traces can be maintained on disk for the time spans specified in the Log to historical

database lifespan data field. LookoutDirect monitors the status of your hard drive and generates an alarm when your disk falls below 500 KB of available space.

Use discretion when determining Deviation settings on each trace of data. If

Deviation is not specified, any change of an analog value results in a new point being logged to disk, and you might generate too much data. If the

Deviation setting is too large, very little information might be saved to disk.




Event Logger

When you want to create a chronological schedule of events or an audit trail, log LookoutDirect events.You can log all events: operator commands, Event objects, and all global events (running LookoutDirect, closing

LookoutDirect, opening a process file, closing a process file, entering edit mode, exiting edit mode, and logging on and off).

LookoutDirect system events, such as logging on and logging off, or entering and exiting edit mode, are automatically logged as events by LookoutDirect.

Other events, such as adjusting the value of a Pot object, are only logged if you select the Log events option when you create or modify the object.

When LookoutDirect logs an event, it also logs the account name (the operator), date and time of the event, name of the object adjusted, and the previous and subsequent settings of the object. Because all of this information is logged, you create an exhaustive audit trail for that specific workstation.

Use the Event object class to define and log your own event messages based on a user-defined trigger. For additional information, refer to the Event object class in the online help or the PDF LookoutDirect Object Reference Manual.

Event Data Location

LookoutDirect stores event files in the same Citadel database that holds

LookoutDirect alarms and LookoutDirect data for any LookoutDirect process.

To view events in real time, select the Show Events or the Show Alarms &

Events option in the Alarm Filters dialog box. Print events the same way you print alarms, using the appropriate alarm filter settings.

Event Information Overload

The event logger can store information on an individual object instance for

Switches, Pots, and Pushbuttons. Every time you flip a Switch, adjust a Pot, or depress a Pushbutton, LookoutDirect logs the event to disk. If you enable the Event Logger for all instances of these object classes, you might collect more data than you need.

By selectively enabling the Event Logger on critical Switches, Pots, and

Pushbuttons, you cut down on the amount of information logged to the event file. For example, you might place a dozen Switches on a control panel, but only one of those twelve requires data logging. Rather than log events for all

12 Switches, enable the Event Logger only on that single switch.



Report Generation

Control Panel Reports

Panel objects have a special data member named print

. When print changes from

FALSE

to

TRUE

, LookoutDirect copies a picture of the control panel and sends that copy to your printer using the Windows Print Manager.

You could use this to record the status of a particular panel at a particular time. For more information, refer to the Panel description in the online PDF

Object Reference Manual or the online help.

To configure your custom report, design a control panel and connect a logical trigger signal to the panel. You can connect any logical expression to the print

member. The control panel does not have to be visible to be printed.

Therefore, an operator can view one screen (panel) while printing another screen. For more information about making connections, refer to the

LookoutDirect Getting Started Guide.

LookoutDirect determines the printed panel size based on dimensions entered in the Revise control panel settings dialog box. There are several ways to access this dialog box. First, make sure you are in edit mode. Then, do one of the following:

• Right-click on a panel title bar.

• Right-click on a panel in the Object Explorer and select Properties.

• Select Object»Modify, then select a panel from the list.


When Panel type is set to Normal, LookoutDirect assumes that the panel is maximized. Even though your control panel might be maximized,

LookoutDirect prints only the area defined by your Panel object Width and



Height settings. For example, you might have a panel that looks like the following when maximized.

The panel shown above has a specified Height of 300 pixels and a Width of

400 pixels. At a video resolution of 800

×

600, the printed panel would look something like the following figure.


Modify the Height and Width dimensions of your Panel object to match your screen resolution. This problem applies only to Normal style panels. Popup

7-12w ww.Automationdirect.com


and Popup no icon style panels print according to the WYSIWYG principle

(What You See Is What You Get).

Third-Party Reports

You can generate reports using LookoutDirect and a third-party spreadsheet program. Current spreadsheet software provides extensive macro command capabilities you can use to quickly generate reports from LookoutDirect. You can write Excel macros that prompt you for the report date, automatically open the correct spreadsheet file(s), extract the data, and print reports with combinations of numeric tables and graphs. You can launch these macros from LookoutDirect or automatically invoke them using predefined timers.





8

Structured Query Language

This chapter describes Structured Query Language (SQL), Open Database

Connectivity (ODBC), and accessing Citadel data using both SQL and ODBC.

Introduction

What is ODBC?

ODBC is a standard developed by Microsoft. It defines the mechanisms for accessing data residing in database management systems (DBMSs). Nearly all Windows-based applications that can retrieve data from a database support

ODBC.

What is SQL?

The Citadel historical database includes an Open Database Connectivity

(ODBC) driver, which enables other applications to directly retrieve data from Citadel using Structured Query Language (SQL) queries.

Structured Query Language (SQL) is an industry-standard language used for retrieving, updating, and managing data. In LookoutDirect, you can use SQL to build queries to extract data from Citadel. The Citadel ODBC driver also includes many built-in data transforms to simplify statistical analysis of retrieved data.



Chapter 8 Structured Query Language

Creating a Citadel ODBC Data Source

Use the following procedure to create a Citadel ODBC data source for use with LookoutDirect.

1.

Click the Windows Start button and select Settings»Control Panel.

2.

Run the ODBC applet. It might be called ODBC or ODBC Data

Sources or something similar, depending on your operating system version number.

Note

Shut down all ODBC applications, such as databases, spreadsheets, word processors, and Microsoft Query, before you run the ODBC applet.

3.

Select the User DSN tab or the System DSN tab, depending on which type of data source you want to create. User DSNs are only visible to the user who created them on the current machine. System DSNs are available to all users on the current machine.

4.

Click on the Add button. The following dialog box appears.



5.

Select National Instruments Citadel 4 Database, then click Finish.

6.

In the National Instruments Citadel ODBC Setup dialog box, fill in the Data Source Name, Description, and Database Path fields. a.

The Data Source Name is the name that ODBC applications use to select your data source.

b.

Description is a free-form text string you can enter to describe the data source.

c.

Database Path should match the location of the Citadel database you intend to access. Use a fully qualified path to a remote computer if you are accessing the Citadel database on a remote computer, such as

\\Tripper\c:\lookout\database

.




The Data Source Name must be different from any other ODBC data source name. The Description is arbitrary. The Database Path gives the location of the folder where the data for this source is stored. In

LookoutDirect 4, it is possible to configure multiple Citadel databases. If you do so, you probably want to configure one ODBC data source for each. If you used the Options»System dialog box in LookoutDirect to configure a default Citadel database on the local computer, you should create a data source for the location specified in the Default Path field in the LookoutDirect System Options dialog box. If you used

File»Modify Process in LookoutDirect to configure a different database for a process, you probably want to create a separate data source for that process using the location specified in the Citadel Database Folder field of the LookoutDirect Modify Process dialog box.

7.

Click on OK in the Setup dialog box, then click on OK in the ODBC

Data Source Administrator dialog box.

Note

Some applications are not completely ODBC compliant. If you plan to use Microsoft

Query, Microsoft Access, or Visual Basic, make sure Maximum Column Name Length does not exceed 62 characters. These applications cannot handle longer names. Applications that are completely ODBC compliant can handle names up to 126 characters long. All traces whose names exceed the Maximum Column Name Length are excluded from queries.

Because LookoutDirect objects may include network path information in their names, and because you can arrange LookoutDirect objects in hierarchies inside your processes, you may find it easy to exceed the 62 and 126 character limitations of ODBC. Consideration given to naming and organizing objects can minimize the risk of encountering this difficulty.



If you plan to use Microsoft Access or Visual Basic, select Convert special

characters to force LookoutDirect names into an accepted format by replacing characters within the names with the characters in Table 8-1.

The special characters changed in LookoutDirect 4. If you are converting

LookoutDirect processes from a version earlier than LookoutDirect 4, you might have to rewrite any SQL queries you set up in your earlier processes.

Table 8-1. Special Access SQL Characters

Special Character

period ( . )

Converted Character

at sign ( @ )

Accessing Citadel Data

Traces Table

The ODBC driver presents Citadel data to other applications as a traces table.

The table contains a field or column for each data member logged to the

Citadel database and three fields you can use to specify query criteria and to time stamp retrieved data: Interval, LocalTime, and UTCTime.

Interval specifies the query value sample rate. Interval can range from

10 ms to several years. Interval defaults to 1 (one day). WEEK is a standard seven days, but MONTH and YEAR account for different month lengths and leap years.

Because Citadel is event-driven, it only logs a value when the value changes.

Using Interval, you can query Citadel for values evenly spaced over a period of time.

LocalTime and UTCTime are time-stamps that indicate when values are logged. Citadel stores the time in UTCTime format and derives LocalTime from the stored time.

The following where clause

query uses Interval and LocalTime to select data over a specified time at one-minute intervals. Notice that time and date formats are the same as those used in LookoutDirect.

SELECT * FROM Traces

WHERE LocalTime>“12/1 10:00”

AND LocalTime<“12/2 13:00”

AND Interval=“1:00”




Points Table

The Points table is used to retrieve the actual values logged by LookoutDirect for a data member and the times they were logged. As LookoutDirect logs values for data members asynchronously, there is no correlation between the timestamps for one data member and another. For this reason, when querying the Points table, you may only query one data member at a time.

The where clause using LocalTime and UTCTime is supported for the Points table; however, Interval is not relevant to the Points table. The data transforms are also not relevant to the Points table and are not supported.

An example of a query using the Points table could be

SELECT LocalTime, Pot1 FROM Points

WHERE LocalTime > "12/1 10:00" AND

LocalTime < "12/2 10:00"

Data Transforms

Command

Min{Datapoint}

Max{Datapoint}

Avg{Datapoint}

Stdev{Datapoint}

Starts{Datapoint}

Stops{Datapoint}

ETM{Datapoint}

Qual{Datapoint}

Your queries can include special commands that perform data transforms to manipulate and analyze historical data. Table 8-2 lists data transform commands.

Table 8-2. Data Transform Commands

Transformation

Returns the minimum for

Datapoint

across the interval.

Returns the maximum for

Datapoint


Returns the average for

Datapoint


Returns the standard deviation for

Datapoint


Returns the number of starts (that is, the number of transitions from OFF to ON) for

Datapoint

across the interval. For numeric points, 0.0 is interpreted as OFF, and all other numbers are treated as ON.

Returns the number of stops (that is, the number of transitions from ON to OFF) for

Datapoint


Returns the amount of time

Datapoint

was in the ON state across the interval.

There might be gaps in the historical data traces in Citadel because of machine shutdown, LookoutDirect shutdown, or a similar occurrences.

Qual returns the ratio of time for which valid data exists for

Datapoint

across the interval to the length of the interval itself. If valid data exists for only one-half of the interval, Qual returns 0.5.



Using these data transforms, you can directly calculate and retrieve complex information from the database such as averages and standard deviations, so you do not need to extract raw data and then manipulate it in another application.

For example, you need to know how many times a compressor motor started in December. You also need to know its total runtime for the month. Use the following query to get your answers:

SELECT“Starts{PLC.MotorRun}”,

“ETM{PLC.MotorRun}”

FROM Traces

WHERE LocalTime>=“12/1/95”

AND LocalTime<“1/1/96”

AND Interval=“31”

SQL Examples

The following examples are typical query statements; however, your queries might be much more involved, depending on your system requirements.

SELECT *

FROM Traces

Retrieves the current value of every data member logged to Citadel.

Because your query does not occur at the same moment in time as a PLC poll, signals scanned from PLCs are not included in the retrieved data.

SELECT *

FROM Traces

WHERE Interval=“0:01”

Retrieves the value of every data member logged today in one-second increments. Notice that the interval value is enclosed in quotation marks.

SELECT LocalTime, “Pot1”

FROM Traces

WHERE LocalTime>“8:50”

AND Interval=“0:01”

Retrieves and time stamps the value of Pot1 in one-second increments from 8:50 this morning to now. Names are enclosed by quotes.

SELECT LocalTime, “AB1.I:3”, “Max{AB1.I:3}”

FROM Traces

WHERE LocalTime>“10/1/95”

AND LocalTime<“11/1/95”

AND Interval=“1:00”




Retrieves and time stamps an Allen-Bradley PLC input in one-minute intervals for the month of October. This query also indicates the highest occurring input value of each minute.

SELECT LocalTime, “OVEN1_SP”, “PLC.OVEN1_PV”,

“Max{PLC.OVEN1_PV}”, “Min{PLC.OVEN1_PV}”,

“Avg{PLC.OVEN1_PV}”

FROM Traces

WHERE LocalTime>=“14:00”

AND LocalTime <“15:00”

AND Interval=“1:00:00”

Retrieves an oven temperature at 3:00 p.m. and shows the highest, lowest, and average temperatures between 2 p.m. and 3 p.m.

Accessing Citadel Data with Microsoft Query

1.

Launch Microsoft Query.

2.

Choose File»New. If the Citadel data source is not visible, you must create it. If it is visible, skip to step 3.

a.

Select the

<New Data Source>

entry in the Databases tab. Make sure the Use the Query Wizard to create/edit queries option is not selected.


b.

The Create New Data Source dialog box appears. Fill in the fields as shown in the following illustration.



c.

Click on the Connect button. The National Instruments Citadel

ODBC Setup dialog box appears. Fill in the fields as shown in the following illustration. Enter the location of your database in the

Database Path field.

© Automationdirect.com d.

Click on OK. The Create New Data Source dialog box reappears, and should look like the following illustration.



e.

Do not select a default table or save your ID and password. Click on

OK. The Choose Data Source dialog box appears, this time with the Citadel database as one of your data source choices. Choose

Citadel as your data source and click on OK.

3.

Select the

Citadel

data source. Make sure the Use the Query Wizard

to create/edit queries option is not selected.

Note

If Microsoft Query is unable to connect to Citadel, make sure you have logged data to

Citadel and entered the correct database path in the ODBC Setup dialog box.

Note

If Citadel is not listed in the Data Source dialog box, make sure you have created

Citadel as a data source. See the Creating a Citadel ODBC Data Source section for more information.



4.

In the Add Tables dialog box, double-click

Traces

or

Points

, depending on whether you want to view raw data (

Points

) or resampled data (

Traces

). In the following figure,

Traces

are used.

Query

Window

Traces

Window

5.

Close the dialog box.

Microsoft Query presents the full Query Window with the

Traces

and

Points

tables. The names in these tables are a comprehensive list of all name values that have been logged to Citadel.

SQL Button View Criteria Button


6.

To view a trace, double-click on or drag the field you want to view to a blank column in the data pane. In the figure above,

LocalTime

and



"\\PAROIKOS\My_Server\PLC_Simulator@amplitude"

have been dragged down.

7.

To view a data transform value, enter the function directly into a blank column. For example, to view the minimum value of

PLC_Simulator.amplitude

, you would enter

“min{\\PAROIKOS\My_Server\PLC_Simulator@amplitude}”

.

You must include the quotation marks and braces.

The data set in the figure above was retrieved using no specific criteria, so the ODBC driver used the default. Although there are several ways to specify criteria, this example uses the criteria pane.

8.

Click on the View Criteria button. The pane appears in the Query window.

9.

Add a field to the criteria pane by double-clicking on the field, or by dragging it to the blank column in the criteria pane. In the following example, an Interval criteria of one minute was chosen.

Criteria Pane


When you enter qualifying criteria values, use the syntax demonstrated in SQL Examples earlier in this chapter.

As soon as you specify criteria, Microsoft Query retrieves the specified data. You can save your query at any stage of development, and as you build your query, the application builds an SQL statement.



10. Click on the SQL button to view or edit the query statement.

Accessing Citadel Data with Microsoft Excel

1.

Launch Excel.

2.

Choose Data»Get External Data»Create New Query. This Excel command directly launches Microsoft Query.

3.

Use an existing query or create a new one. See the section Accessing

Citadel Data with Microsoft Query for information on querying.

4.

When you finish building your query, return the result set with the

File»Return Data to Microsoft Excel command. Excel prompts you with the Get External Data dialog box, enabling you to change or confirm the destination cells of the result set. If you want to query Citadel later to update the result set, check the Keep Query Definition checkbox.

5.

Click on OK to write the data to an Excel worksheet.

6.

To update your result set, select any cell within the worksheet result set, choose Data»Get External Data, and click on the Refresh button.

Accessing Citadel Data with Microsoft Access

Note

The SQL/92 standard states that a delimited identifier is any string of no more than

128 characters enclosed in quotation marks. It further states that characters within a delimited identifier are exempt from SQL syntax checking. Unfortunately, Microsoft Access performs its own syntax checking for ODBC queries using a non-standard SQL syntax—even within delimited identifiers. For this reason, National Instruments provides a Convert Special

Characters selection in the Citadel ODBC Setup dialog box. When selected, the ODBC driver converts the special characters to accepted Access characters. Refer to Table 8-1 for a complete list of special characters.

When you query Citadel using Microsoft Access, you must use the Microsoft

Access non-standard SQL syntax in your select statement. Remember to consider the following elements:




• Convert special characters for Access compatibility (see Table 8-1)

• Place double quotes around LookoutDirect trace names to identify them as delimited identifiers

• Enclose identifiers in square brackets ([ ])

• Place pound signs (#) around time stamps

For example, to retrieve

LocalTime

,

Pot1

, and

Tiway1.V101

, where

LocalTime

is greater than 11/20/95 18:00:00, and where

Interval

is one second, enter the following query:

SELECT LocalTime, ["Pot1"], ["Tiway1@V101"]

FROM Traces

WHERE LocalTime > #11/20/95 6:00:00 PM#

AND Interval = '0:01'

1.

To query Citadel from within Microsoft Access, open a database and select File»Get External Data»Link Table. The Link dialog box appears, as shown in the following illustration.


2.

Set the Files of type field to ODBC databases(). The Select Data

Source dialog box appears.



3.

Choose the Machine Data Source tab.

4.

Highlight Citadel 4.0 Database.dsn, as shown in following illustration.

(This example assumes you have created a Citadel data source as described in the Creating a Citadel ODBC Data Source section. If you have not created a Citadel data source, you may not be able to complete this example exercise.)


5.

Click on OK. The Link Tables dialog box appears.



6.

Choose Traces. The new table links to your database.

7.

The Select Unique Record Identifier dialog box appears. Click on

Cancel, because LookoutDirect does not support unique record identifiers.

8.

At this point, you can build queries in Access to extract data directly from the Citadel database. See your Microsoft Access documentation for more detailed information on this process.


Chapter 8

Accessing Citadel Data with Visual Basic

Structured Query Language

Note

Visual Basic software relies on Microsoft Access DLLs for performing ODBC queries. Because it uses the Access non-standard SQL syntax, be sure that Convert Special

Characters is selected in the Citadel ODBC Setup dialog box. Refer to the note under

Accessing Citadel Data with Microsoft Access.

You use the Citadel ODBC Driver in Visual Basic the same way you would use any other ODBC driver. To retrieve and view data, you have to create a data control and at least one text control.

1.

Place a data control on an open form.

2.

Set its Connect property to

DSN=Citadel

and double-click on its

Record Source property to identify

Traces

as its source table.

3.

If you want to select all of the data for all traces in the Citadel database, leave the Record Source property set to

Traces

. If you want to narrow your query, enter an SQL select statement in the Record Source property.

For example, to retrieve

LocalTime

,

Pot1

, and

AB1.I:3

where

LocalTime

is greater than 11/20/95 18:00:00 and less than 18:30:00, and where

Interval

is one minute, enter the following query:

SELECT LocalTime, ["Pot1"], ["AB1@I:3"]

FROM Traces

WHERE LocalTime > #11/20/95 6:00:00 PM#

AND LocalTime < #11/20/95 6:30:00 PM#

AND Interval = '1:0'

Note

Remember to use the Microsoft Access SQL syntax in the select statement, convert special characters for Access compatibility (see Table 8-1), place double quotes around

LookoutDirect trace names to identify them as delimited identifiers, enclose identifiers in square brackets ([ ]), and place pound signs (#) around time stamps.

4.

Place a text control on the form.

5.

Set its Data Source property to the name of your data control—for example,

Data1

.

6.

Click on the Data Field property to highlight it and then use the property sheet drop-down combo box to select the desired field name. All logged data members should be listed including

LocalTime

,

Interval

, and

Pot1

.

7.

Repeat steps 4 through 6 for each data member you want to display on your form.




If you are using Visual Basic 4 or later, you might get a Visual Basic warning telling you

Object variable or with block variable not set

.

The following steps should help if this problem arises.

1.

Make sure that the Citadel ODBC is properly installed. Select Control

Panel»32-bit ODBC and choose the Users DSN tab. You should see your Citadel data source listed. If you do not, you must create it. See

Creating a Citadel ODBC Data Source for more information.

2.

Make sure you have placed a Data Control on your open form.

3.

Set the

Connect

property of the Data Control to

ODBC;DSN=Citadel

(or any other name you defined in the Users DSN tab in step 1). You should now be able to see

Traces

in the Record Source property.


9

Alarms and Events

The LookoutDirect alarm service keeps track of error messages and any process elements you have defined alarm conditions for. You can define alarm conditions for most LookoutDirect objects and data members. You can filter, display, log, and print alarms. You can also organize alarms into hierarchal areas to aid in performing the other alarm tasks. All LookoutDirect alarms and events are automatically logged to the Citadel database.

When the alarm display window is visible, a pair of thin lines serve as a cursor. You can scroll through the alarms with your keyboard cursor keys, selecting individual alarms with the spacebar.

Right-clicking in the alarm window opens the Alarms menu, which includes options you can use to acknowledge alarms and access all other alarm properties.

Defining Alarm Conditions

You can create an alarm condition in two ways. First, you can define alarm parameters when modifying an object database (Database-Generated

Alarms). Second, you can use Alarm objects to define alarm conditions

(Alarm Object method).

Database-Generated Alarms

Most objects contain numeric or logical data members. If they exceed specified conditions, you want LookoutDirect to generate an alarm. These conditions can include high, low, high-high, and low-low. Select

Object»Edit Database or right-click on the object in the LookoutDirect

Object Explorer to modify alarm parameters for an object data member in its database dialog box as illustrated in the following figure. You can browse for an existing alarm area for the alarms, or create a new one.



Chapter 9 Alarms and Events

Alarm Objects

This method offers the most efficient way to define standard or simple alarm conditions. Furthermore, this method is especially useful when you configure alarms for data that originate from objects with large databases, like Driver objects and DataTable objects.

For dedicated Alarm objects, you define and create Alarm objects on an individual basis with the Object»Create command, or by right-clicking on a process in the LookoutDirect Object Explorer. The Create Alarms dialog box appears, as shown in the following illustration.



You can create alarms that are triggered by any event or combination of events you specify in the Create Alarm dialog box using as simple or complex an alarm criterion as needed. You do not have to use the traditional set of alarm conditions (that is, High, Low, Rate-of-Change). See the Alarm topic in your online help or in the online PDF LookoutDirect Object

Reference Manual for additional information.

Alarm objects are not the only source of alarm signals. Most object classes generate their own alarm signals—Driver, Spreadsheet, and Expression objects can also generate alarms.

Several object classes generate circular reference alarms. A circular reference alarm defines a condition where the signal generated by an object is sent back to that object as a parameter, either directly or indirectly. Circular references are always priority 10 alarms, and you should correct them during process file testing.




The Alarm Subsystem

You use the alarm subsystem, which is comprised of several components, to control how alarms are displayed, acknowledged, printed, grouped into areas, prioritized, and filtered. Before you implement a structure for your alarming system, you should understand these various components.

Selecting Processes to Monitor for Alarms

Before you can monitor alarms or events running on other computers, you must add the processes those events might rise from to the list of processes your monitoring computer is keeping track of. To select processes to monitor, choose Alarms»Select Processes. The following dialog box appears.

Alarm Areas


Select the processes in the Available Processes list that you want to monitor and click the Add button. To stop monitoring a process, select the process in the Selected Processes list and click the Delete button.

For organizational purposes, you can classify alarms into areas. Alarm areas allow operators to filter unwanted alarms and acknowledge alarms on an area-by-area basis.

You can create any number of alarm areas and assign any number of alarms to any area. However, you should carefully plan your alarming structure so operators can filter alarms by meaningful categories. With a carefully planned



structure, you can handle specific areas and/or priorities if your system experiences a large number of alarms.

Note

One reason to decide on your alarm area arrangement in advance has to do with maintaining alarm data continuity. If you move alarm notification from one area to another, only new notifications will be stored in the new area. To access old alarms, you have to search in the original area.

LookoutDirect has hierarchal organization of alarms based on alarm areas.

When you create an alarm area, LookoutDirect creates a folder in the global

$Alarm object to hold those alarms. These folders make browsing for alarm areas when setting filters more convenient.

When you first start LookoutDirect, it has one default alarm area called

LookoutDirect. There are also a number of alarm areas built into

LookoutDirect that become visible when you create or open a process that uses one of the objects associated with those areas. Table 9-1 lists the various alarm areas.

Alarm Area

LookoutDirect

Serial Ports

(comm)

Citadel

DDE

Disk

Math

Print

Table 9-1. Lookout

Direct

Alarm Areas

Description

LookoutDirect default alarm area. Includes alarms not directed to a specific alarm area.

Alarms involving serial ports and serial communication.

Alarms concerning the Citadel database.

Alarms generated by any DDE object or action.

Disk alarms.

Mathematical errors, such as an attempt to divide by zero.

Printer alarms.

You create your own alarm areas by entering an alarm area name in the Area field of the Alarm conditions section of the database dialog box or in the

Alarm area field of the Alarm object.

After you create or activate a LookoutDirect alarm area, that area becomes a part of your Citadel database and appears in the alarm area hierarchy, whether or not the process directing alarms to that area is running.




See the Alarm object in the LookoutDirect online PDF Object Reference

Manual.

Alarm Priorities

Assign each alarm a priority level ranging from 1 to 10, where Priority 1 is the lowest priority alarm and Priority 10 is the highest priority alarm.

Priority 1 alarms do not require operator acknowledgment. When they are deactivated, Priority 1 alarms are removed from the alarm window by

LookoutDirect, regardless of acknowledgment.

You should assign Priority 1 to only minor, inconsequential alarms. Often, priority 1 alarms do not exist in control strategies. If an occurrence is significant enough to be classified as an alarm condition, you should assign a priority level that requires operator acknowledgment.

Priority 2 and higher alarms require operator acknowledgment before they are removed from the alarm list.

The Data files location parameter in the System Options dialog box specifies the root directory for the Citadel database.

Alarm Window

The Alarm window lists all active and unacknowledged alarms. Alarms are listed in chronological order with the most recent alarm at the top of the list.

If there are too many alarms to see at once, you can use the scroll bar at the right of the Alarm window to scroll through the list.

If you have your Alarm window display options set to minimize the window, you can view the alarm window by pressing <Ctrl-A>, selecting

Alarms»Show, or clicking on the alarm indicator box on the far right side of the LookoutDirect status bar at the bottom of the screen, shown in the following figure.

To quickly identify alarm status, use the LookoutDirect Alarm window color scheme, as defined in Table 9-2.



Table 9-2. Alarm Colors

Color Alarm Status

Red Active

Blue Unacknowledged, Inactive

Red and Black Acknowledged, Active

(Alarm information, including time, description, priority, and name, appears in black and the area in red).

When you acknowledge an inactive alarm or an acknowledged alarm deactivates, LookoutDirect removes the alarm from the alarm window.

Because a new line is added to the list every time the alarm activates,

LookoutDirect might list the same alarm condition multiple times in the alarm window.

When you acknowledge an alarm or a block of alarms, LookoutDirect prompts you to enter a comment, which is logged to the database along with the acknowledgement time and operator. This comment is optional, and you can omit entering it if there is nothing to make a note of.

To view detailed information about a particular alarm, right-click on the alarm in the alarm window and select Properties.

Alarm Display Options

The Alarm window displays unacknowledged alarms that meet alarm filter requirements you set with the Alarm Filter dialog box. With the

Alarms»Display Options command, you can change the display style of the

Alarm window. The Alarm Display Options dialog box appears, as shown in the following figure.


The Window style determines the position of the alarm window in the

LookoutDirect workspace. If you select Floating, the alarm window appears



as a pop-up style control panel that you can resize and move on the screen.

You can minimize a floating alarm window at any time.

If you use either the Top or Bottom window type, the Window height specifies the number of alarms LookoutDirect can display in the Alarm window. The actual height of the Alarm window adjusts automatically depending on the selected font and Window height setting. You can resize a floating Alarm window at any time with the sizing border. If more alarms occur than can be displayed in the Alarm window at once, a scroll bar appears along the right side of the window.

The following illustration shows an example of an Alarm window with

Window style set to Bottom and Window height set to 4.

Alarm Filters

To filter the alarms that appear in your alarm window, select Alarms»Filter

Options, or right-click in the alarm window and select Filter Options. The following dialog box appears.


To monitor alarms with specific priorities, set the Min and Max values of the

Priority criterion.



Set User Name to restrict your alarm monitoring to alarms generated while that particular user is logged on. You can only select one user name at a time, but you can use wild card characters to widen the scope of the alarms reported.

Set Ack User Name to restrict your alarm monitoring to alarms acknowledged by that particular user. You can only enter one user name at a time, but you can use wild card characters to widen the scope of the alarms reported.

The Ack Comment filter restricts your alarms displayed to those with the specified acknowledgement comment.

Set Object Name to restrict your alarm monitoring to alarms involving the name you enter. You can only enter one name at a time, but you can use wild card characters to widen the scope of those objects reported.

Set Description to restrict your monitoring alarms that meet your criteria.

You can only choose one description category at a time, but you can use wild card characters to widen the scope of the alarms reported. The LookoutDirect categories HiHi, Hi, Lo, or LoLo are added as a prefix to any descriptions and are ignored by description filtering.

Set Area Name to restrict your monitoring to the alarm area you choose. You can only enter one alarm area at a time.

Use the Browse Areas button to locate and select the alarm area you want to use as a filter.

You can choose to have the LookoutDirect Alarm window show alarms only, events only, or both alarms and events by checking the appropriate box in the

Show section of this dialog box.

Use the parameters in the Old Alarms section to display alarms after they have been acknowledged.

Select Audible Alarms to enable a sound alert when an alarm takes place.

The sound depends on your windows system setting for error sounds.

The Alarm Alert box in the right corner of the status bar displays the number of alarms currently visible in the alarm window.


If you are filtering alarms, alarms that do not meet your filter criteria do not show up in this status bar count. To see all alarms, click on the Display All



button in the Alarm Filters dialog box, then click on OK. The alarm window displays all active and unacknowledged alarms. The status bar reflects the change.

Alarm Print

You can print alarms in LookoutDirect, based on your filtering. To print your alarms, select Alarms»Print. The following dialog box appears.


Select the time range you want to print alarms and events from with the items in the Print Range section of the dialog box. Notice that when you define your own range, you use month, day, and year, followed by hour and minute.

The Printouts selections determine the exact alarm information included in your printout. Snapshot only prints the status of alarms at the beginning of the specified Range but does not indicate what happened during the time span. Journal creates a printout of everything that happened during the time span from the beginning of the Range.

Specific information about each alarm is presented in columnar format.

LookoutDirect prints only the information you designate. Select which columns you want printed in the Columns section of the dialog box.

To print to a comma separated file (

.CSV

), select the Print to CSV file option.

Enter the file names for your journal and snapshot files, including a complete



path to where you want the file written. If you enter a file name only,

LookoutDirect will create the file in the LookoutDirect directory.

Set the format for printing times in the Time Format list.

You can adjust your alarm filters for printing by clicking on the Filter

Options button to access the alarm filter options.

Note

You can print alarms as they happen by specifying a printer port in the Log alarms to field of the System Options dialog box, accessed by selecting Options»System from the menu bar. This works well for a printer directly connected to your computer. To print alarms directly to a network computer, you have to capture a port in the network printer driver and link it to your networked printer. Consult your operating system documentation for detailed instructions on how to capture a port for a printer driver.

Alarm Acknowledgment

Before you can acknowledge an alarm, you must select it. To select an alarm, click on the alarm line in the Alarm window. Highlighting indicates that the alarm is selected. To deselect an alarm, click on the alarm line. <Ctrl-click> to select multiple individual alarms; <Shift-click> to select blocks.

You can access all the acknowledgement options from the Alarms menu item, or by right-clicking in the Alarm window.

Right-click an alarm in the window and choose Select All to select all alarms for acknowledgment. You can also select Acknowledge All. Because selecting each alarm individually can be very time consuming, either technique can be especially useful if your process is experiencing a high number of alarms.

Right-click and select Deselect All to deselect all alarms that were previously selected for acknowledgment. If you want to deselect only some of the alarms, <Ctrl-click> on the individual alarms you want deselected.

Selecting Acknowledge acknowledges alarms that you have selected for acknowledgment. If you have not selected alarms when you invoke this command, the following message box appears.




If you select one or more alarms for acknowledgment, a dialog box appears for an operator to enter a comment concerning the alarm. Comments are optional, and you can click on OK to finish acknowledging alarms without entering a comment.

You can search the database for alarms or print out the alarms based on comments, so using certain standard comments (in addition to comments on specific circumstances) can make the filtering process easier. You should create your own master list of standard comments if you want your operators to use them.

You might want further information about a specific alarm or event.

Right-click on an alarm and select Properties. The following dialog box listing specific information about the alarm or event appears.



You can scroll through alarms and events using the Previous and Next buttons.

Acknowledging Alarms Programatically

By connecting to the appropriate data members of the global $Alarm object, you can acknowledge alarms programmatically with Pushbuttons or other logical expressions. This way, you can bypass the menu commands, or acknowledge alarms from remote LookoutDirect network nodes. For instance, you could create a single Pushbutton that acknowledges all alarms, or you could create multiple Pushbuttons for acknowledging specific areas of alarms.

With the $Alarm object, you can access numeric signals that indicate the number of currently active alarms or the number of unacknowledged alarms in a particular area. For more information, refer to $Alarm in your online help or in the online PDF LookoutDirect Object Reference Manual.





10

Redundancy

With LookoutDirect, you can configure two process control computers for redundancy, providing automatic transfer of control if the primary computer should fail. Redundancy only applies to systems that implement networking of multiple LookoutDirect nodes. It does not apply to stand-alone systems.

You should understand process files (

.L4P

) and state files (

.L4T

) before you attempt to use this chapter.

Note

In versions of LookoutDirect earlier than LookoutDirect 4, redundancy was handled through NetDDE. National Instruments recommends you use LookoutDirect’s TCP/IP-based networking when possible, but you can still use your old NetDDE-based processes with the newer version of redundancy. However, you must equip your backup computer with a monitor and load process like the one described in the Setting up the Standby Process and

Computer section of this chapter. You must also modify the process properties of both primary and standby processes to handle state file and data logging paths appropriately, as described in the Implementing Redundancy section.

No other alterations should be necessary to upgrade your redundancy processes, though you should test the new arrangement thoroughly. The need remains for following NetDDE naming conventions as well as the other instructions given in Appendix A, Networking With

DDE. If your client process uses NetDDE in shifting access from one computer to another, it will continue to work in the current version of LookoutDirect.

You set up computer redundancy using the LookoutDirect Monitor, Loader, and Symbolic Link objects.

Standby refers to a network configuration in which one computer is designated the primary computer and another is designated the standby computer. The primary computer normally monitors and controls the process while the standby computer monitors the primary computer. If the standby computer quits receiving information from the primary computer, the standby computer automatically takes over and assumes the role of the primary computer. The following illustration depicts a typical LookoutDirect network structure with the standby option configured.


10-1 Getting Started Guide

Chapter 10 Redundancy

I/O hardware could be PLCs, RTUs, controllers, or any other device Lookout communicates with.

primary.l4p

PLC standbycontrol.l4p

copy of primary.l4p

Lookout Lookout

client.l4p

Lookout

Primary Machine Standby Machine

Local Area Network

Standby Basics

There are three basic principles assumed in the illustration shown above.

First, both the primary and standby computers must have direct access to your field I/O. If the primary computer fails for any reason, you cannot rely on it anywhere in your backup strategy. Your standby computer must have the same direct access to all your I/O, because it will assume the responsibility of the primary computer. There are several ways to accomplish this, depending on your hardware, network, and communications topology.

The second principle is that you can designate any node on the network as the standby computer. It does not need to be the closest physical computer on the network, though this is typically the case due to the restraints imposed by the first principle. During normal operations (that is, while the primary computer is functioning properly), the standby computer is just another computer on the network.

However, the standby computer should also have a copy of the primary computer process file in its LookoutDirect directory,

PRIMARY.L4P

in this example. As soon as the standby computer fails to receive a signal from the primary computer, it automatically loads its local copy of the

PRIMARY.L4P

file. From that point on, the standby node assumes the role of the primary computer, and all other computers running LookoutDirect processes automatically recognize this fact. At the same time, client processes accessing a server running on the primary computer switch from accessing the primary to accessing the standby.



When the primary computer comes back up on the network, the standby computer and any client processes affected return to their previous operation.

The third standby principle takes no additional configuration on your part, but is important to understand for peace of mind. A stand-alone LookoutDirect application is responsible for periodically updating its own state file. In a standby system configuration, the primary computer not only updates its own state file, but also the state file of the standby computer. When a failover occurs, the standby computer takes over where the primary computer left off, ensuring bumpless transfer of control (meaning a transfer without discontinuities in control values).

Failover Scenarios

There are four reasons for the standby computer to take control of the process.

• The primary computer is down (that is, it is not turned on, Windows is not running, or an application fault has locked the computer).

• The primary computer is running, but it is not running LookoutDirect.

• The primary computer is running LookoutDirect, but it is not running the correct process file.

• The primary computer is running the correct process file within

LookoutDirect, but the two computers cannot communicate over the network.

The purpose of the standby feature is to provide automatic failover to a second computer, restoring your LookoutDirect network to its original setup

(that is, with the primary computer running its

PRIMARY.L4P

file and the standby computer running its monitor process).




Configuring Standby

For LookoutDirect to provide standby operation, all the computers involved must be properly set up on your network. If your computers passed the ping test described in the Testing TCP/IP section of Chapter 1, Installing

LookoutDirect, in the Getting Started with LookoutDirect manual, you should be able to implement redundancy with no difficulties. If you cannot ping each computer necessary for your backup system to work, consult your network administrator.

Enabling File Sharing in Windows 98/95 and Windows NT

One part of proper redundancy is making sure that LookoutDirect has the most recent state file for a process available when it loads that process. This maximizes your chance of a bumpless transfer of control. For this to occur, your computers must have file sharing permission with each other.

1.

Configure the computers you need to share files between using the sharing options in the Network control panel, as shown in the following illustration.


2.

Select the LookoutDirect directory on the standby computer and configure it to be shared, as shown in the following illustration.



3.

Using the Add option, add the authorized computers you want to be able to share to. Make sure full access privileges are granted.

Time Synchronization with Standby Computers

If timing and time-stamped data are crucial to your backup system, consider synchronizing both your primary and secondary computers to a third computer.

In any case, you should make certain that your primary, backup, and client computers are all appropriately synchronized. See the Time

Synchronization section of Chapter 4, Networking, for detailed information about time synchronization.




Implementing Redundancy

To set up your redundancy system, you must configure your primary and standby processes correctly and incorporate certain LookoutDirect objects in primary, standby, and client processes.

Redundancy Overview

A LookoutDirect Monitor object watches the process running on the primary computer. When that process disappears from the network, the Monitor signals the other elements of the LookoutDirect redundancy system into action. When the primary computer and process reappear on the network, the

Monitor object signals the standby process and clients to return to their previous mode of operation.

A LookoutDirect Loader object handles the job of loading and unloading the standby process on command from a LookoutDirect Monitor object.

A LookoutDirect Symbolic Link redirects a client process from interaction with the primary process to interaction with the secondary process when signaled by a Monitor object. When the Monitor object signals that the primary process is back on line, the client switches back to interacting with the primary process.

For detailed information on the Monitor, Loader, and Symbolic Link objects used in implementing redundancy, see your LookoutDirect online help or the online PDF LookoutDirect Object Reference Manual.

Setting up the Primary Process and Computer

If your primary process should go down, you want the transfer to be as bumpless as possible. For this to happen, your standby process needs to open with the most current LookoutDirect state file (

.l4t

) available. To do this, configure the State Information options of your process.

1.

When you create your primary process, you do so using the Create

Process dialog box. If you are setting up redundancy on an existing process, you can access these same options by right-clicking on the process name in the LookoutDirect Object Explorer and selecting

Properties. In either case, the following dialog box appears.




2.

Select Save State File with Process File to save the state file in the location where the process file was opened from. This is your local state file for your process.

3.

Select the Save Standby State File checkbox to save one (or more) copies of the state file for your standby process. Enter a complete path, including state file name, to each location to which you want to save a state file. If you are saving the state file to more than one backup or alternative location, separate the paths with the vertical bar (

|

) operator symbol.

In the preceding illustration, LookoutDirect saves the state file to the local directory containing your process file and to the LookoutDirect

4 directory of the standby computer, named TRIPPER in this case.

Remember that you must make sure your primary computer has write permission to the LookoutDirect

4

directory of TRIPPER for this backup state file to work.

When your primary computer goes off line, your process begins to run on your standby computer. The state file the standby computer uses to initialize its version of your process file must be in the directory containing the standby copy of the process file.

When your process opens, LookoutDirect checks the dates of the state files you have selected and uses the most recent file as the state file to initialize values in your process.



4.

Set how often LookoutDirect saves the state file in the Save state file(s)

every [xxxx] minutes field. The LookoutDirect default is 60 minutes.

Your state file save rate should be the same in your primary and backup processes.

Any time LookoutDirect opens this process, it will open with the most recent state file available.

Note

The process file you use on your standby computer must be identical to the process file on your primary computer it is backing up except in one respect. The standby version of the process file need only save its state file to the location specified by your primary computer’s process file. In this way, when your primary computer comes back online, it can locate the most recent version of the state file to use in initializing.

You might think that you would need to alter your process file before moving a copy of it to your standby computer. The LookoutDirect Loader object, however, overrides a number of settings for any process it loads, including the state file information. Therefore, you do not need to alter your process file in any way when you move a copy of it over to your standby computer to be used for redundancy.

Make sure that when your primary computer comes back on line after being down that LookoutDirect loads as soon as the computer boots, and that

LookoutDirect then loads the proper process.

To make sure your computer launches LookoutDirect when it boots, consult your operating system documentation and follow the instructions for your computer. After you have made sure LookoutDirect will launch when your computer boots, follow these steps to make sure LookoutDirect runs your primary process.

1.

Select Options»Startup. The following dialog box appears.


2.

To add a file to your list of startup processes, click on the Add button. A dialog box you use to browse for a file appears. You can autoload as many processes as you want on startup.



3.

Select the file you want to run when LookoutDirect opens, then click on

Open.

4.

Click on OK

Repeat these steps for each process running on your primary computer that you need to run on your standby computer.

You can also reboot a computer, load LookoutDirect, bring a state file up to date, and load a process manually if you choose or if it becomes necessary.

Setting up the Standby Process and Computer

Your standby computer must be connected to your LookoutDirect network and running a copy of LookoutDirect for LookoutDirect redundancy to work.

The standby LookoutDirect must run a simple process to monitor the process being run on your primary computer. When data ceases to be available from the primary computer, this process loads the standby copy of the primary process. When the primary computer comes back on line and data begins to flow from the primary process again, this same process unloads the standby version of the primary process.

Create this standby control process using the following steps.

1.

Create a new process. In this example, it is named

StandbyControl

.

You do not need to have a front panel for this process, at least in this simple case. You can cancel the Create Panel dialog box if you choose.




2.

Create a Monitor object. The following dialog box appears.

3.

Enter the URL to some data member in the process you want to back up from your primary computer. The value of this data member does not matter, nor does it matter if that data member is used by any other

LookoutDirect object. If the Monitor object does not detect the presence of that data member for the amount of time you enter in the seconds field, the Monitor will go high (TRUE).

4.

Create a Loader object. The following dialog box appears.


5.

When using the Loader for redundancy, set the Process Name the same as the name of the process you are standing by for. The Process File should be identical to the process file you intend it to stand in for.

6.

The State Information settings are important for achieving bumpless transfer back to your primary computer and process when they come back on line. The process file LookoutDirect loads using this Loader object will use the state file you configured your primary process to save



on your standby computer. It is important that you update that same state file while the standby process is running, because if it is more recent than the local state file, LookoutDirect on the primary computer will load the updated state file from your standby computer.

Because you earlier set the state file to be located in the LookoutDirect directory of your standby computer, you should select the Save State

File in LookoutDirect Folder option. If you have reason to save copies of the state file in other locations as well, you can select the Save

Standby State File option.

Note

Settings in the Loader object override any settings you might have made when you created or set the properties for your process.

7.

Set how often you want the state file saved in the minutes field.

8.

Set the location for your Citadel database logging to take place, just as you would when creating a new process.

9.

In this example, the Monitor object is named

Monitor1

. Enter

Monitor1=TRUE

in the Load field, and

Monitor1=FALSE

in the

Unload field.

10. Click on OK.

When the primary computer goes off line and the Monitor object goes high, the Loader object loads the standby process. When the primary computer comes back on line, the Monitor object reverts to low and LookoutDirect unloads your standby process.

Configuring Clients for Standby Operation

It is most likely that you will use redundancy for server processes on

LookoutDirect. You may have any number of LookoutDirect client processes running on other computers in your LookoutDirect network. These clients also must respond to a change from primary to standby computers.

When you create a LookoutDirect client process, you always make connections to the server process and not directly to field hardware, frequently by using the remote position source type of connection.

When you create a LookoutDirect client for use with a redundancy-equipped system, you use the LookoutDirect Symbolic Link to switch your client process access from one process to another. Instead of connecting your client objects directly to objects in another process, you connect them to the symbolic representation of those objects. The Symbolic Link can shift from primary to standby process when necessary and your client will continue to function, having made its connections through the Symbolic Link.




1.

To create this kind of client process, you begin by making a Monitor object, just as you did with the standby control process.

You should set your Monitor object to the same setting you used in the standby control process on your standby computer.

2.

You next create a Symbolic Link. The following dialog box appears.

3.

In this example, the Symbolic Link is named

Server

. The symbolic link

[Server]

refers to which server (primary or standby) is currently active. You use the Dynamic field as the source. The following expression is an example of how to set your source.

IF(!Monitor1,"\\paroikos\MainPumpStation","\\TRIPPER\MainPumpStation")

The

IF

operator lets LookoutDirect choose between two processes, depending on the state of the Monitor object. Notice that

Monitor1

(which signifies the

(implicit)

value of the Monitor object) is preceeded by an explanation point. This inverts the value of the Monitor object. In this statement, as long as the Monitor object is not

TRUE

, the primary process running on the computer paroikos is available and the objects in your client link to objects in that process through the Symbolic

Link.



If the primary computer process goes off line for some reason, the

Monitor object goes

TRUE

and your client process will connect to objects in the standby server process running on TRIPPER.

After you have made this preparation, develop your client process as you ordinarily would, except that you make your connections to the

MainPumpStation

process through your symbolic link instead of with the process itself. Use your Symbolic Link to insert expressions, create remoted controls, and display historical data in HyperTrend.





11

Editing Object Databases

LookoutDirect creates the native database of an object automatically when you create the object. The native database is documented at the end of each object class definition in the online help and in the LookoutDirect Object

Reference Manual.

You can create new data members through aliasing, or modify the parameters of any existing native data member. These parameters include such things as alarm setpoints, deviation filters, scaling factors, historical logging, and alias names.

Note

Any object in LookoutDirect can have its native database modified. However, this is most practical for objects with large native databases, such as driver objects and

DataTable objects.

Editing Database Parameters

1.

For the purposes of this illustration, create a Modbus object, the same way you created the a Pot object. Use the name

PLC_1

for your object, and accept the default parameters.

The Modbus object can be added to your system without a physical connection while you are learning to use LookoutDirect. Let the default settings stand when you create the object.

2.

There are two ways to access the dialog box you use to edit a database.

• From the LookoutDirect menu bar, select Object»Edit Database.

In the Edit object database dialog box, navigate to your demo process running on your local computer and select

PLC_1

.



Chapter 11 Editing Object Databases

• In the LookoutDirect Object Explorer, right-click on the object you want to edit the database for, and select Edit Database.



3.

Follow these steps for each data member to be configured: a.

Identify the desired data member by entering it into the Member data field. If you are modifying a data member that has been



previously configured, you can select it from the Configured points list box.

For this example, select

40011

as the modbus data member.

Enter

FlowRate

as the alias.

Note

Parameter fields automatically change depending on the data member you select.

LookoutDirect automatically determines whether the data member is logical or numeric, and presents you with the appropriate parameter attributes.

b.

Configure appropriate parameters shown in the following illustration. See the individual parameter sections in this chapter for details on setting each parameter.

© Automationdirect.com c.

Select Save or Update. (If you are modifying a data member that was previously defined, the Save button changes to an Update button.)

LookoutDirect stores all the new parameter settings for the specified data member when you select Save or Update. In addition, LookoutDirect adds the modified data member to the Configured points list box for future reference. LookoutDirect immediately reflects these changes throughout your configuration.

4.

Select Quit to exit the dialog box.



Numeric Member Parameters

The following diagram and paragraphs describe numeric data member parameters. Logical data members, covered in the following section, share a number of the same parameters.


Alias renames any native data member. You can think of an alias as a sort of nickname. For example, the Modbus driver object includes the native data member

40011

that represents an analog input. You can give this native data member an alias like

FlowRate

. From then on, you can reference the alias

FlowRate

instead of its native name

40011

. All associated parameters (such as Scaling) are also applied to the alias value.

An alias is a good way to insulate your LookoutDirect configuration from changes in your PLC, RTU, or I/O configuration. For example, consider a flow transmitter wired to an analog input at

40011

. You can give

40011

the alias name

FlowRate

, just as you did in the example. Multiple control panels can then display the

FlowRate

data member and numerous other objects in

LookoutDirect can use it. If you later rewire the transmitter to the analog input at

40012

, you need only modify the alias

FlowRate

to reflect the new

I/O address. LookoutDirect instantly reflects this change everywhere

FlowRate

is used.

You can modify all associated parameters of an existing alias except the alias name itself. If you attempt to modify an existing alias name, the Update button changes to a Save button and you will only create a new alias.



Most developers implement aliases on objects with large native databases, such as driver objects (like Modbus and Tiway) and DataTable objects.

Note

An alias is optional in some instances. You can apply alarming and logging parameters to any native data member and save it to the Configured points list without giving it an alias name. Scaling, however, operates somewhat differently. In order to read scaled data, you read it from the alias, not the native data member.

The Description appears as the message text in the alarm window. It can have spaces, and it can be lengthy. You do not have to enter quotes in this field.

Prefix and Suffix are part of the description, but do not appear in the alarm window. They are just additional descriptive text.

Define Scaling by entering Raw units and Eng. units. The raw numeric data member is converted (scaled) to an engineering unit value. The PLC in this example generates a raw value ranging from 6,400 to 32,000. LookoutDirect converts that raw signal to range from 0 mgd to 200 mgd. The conversion is linear. See your hardware specifications and calibration records for the minimum and maximum raw units associated with analog devices. If you leave the Raw units and Eng. units fields blank, LookoutDirect performs no scaling on the signal.

In order to scale this data, you can use an alias in combination with the native data member. Read or write the raw units by connecting to the native data member, and read or write out the engineering units from the aliased value.

Deviation filters out insignificant variations of numeric signals. The following figure shows two values plotted on a trend. One line is the raw unfiltered value. The other, stair-stepped line, represents the filtered value after passing through a Deviation of 2.




The Citadel database also uses Deviation as the criteria which triggers logging of new historical data to disk. See Chapter 7, Logging Data and

Events, in the LookoutDirect Developer’s Manual for more information on logging data.

Use the Forced data field to manually enter a constant value for the data member. When you select the Forced checkbox and enter a value in the field,

LookoutDirect forces the engineering unit value to be equal to the value you entered, regardless of the actual value of the native data member. You might use this when a sensor fails or during sensor maintenance, or any time a PLC receives a bad signal from the transmitter.

Use the Alarm condition parameters to define alarm limits and their associated priorities. LookoutDirect compares the alarm setpoints to the engineering units value (that is, the post-scaled, post-filtered number). If you do not enter scaling parameters, LookoutDirect applies the alarm parameters directly to the raw signal.

You can assign an alias or native data member to any existing alarm Area or you can create a new Area. To create a new Area, enter the new area name in the field. See Chapter 9, Alarms, in the LookoutDirect Developer’s Manual for more information on alarms.

Use the alarm Deadband parameter to prevent fluttering between alarm and normal states when the signal value hovers near an alarm limit. The following figure shows a value plotted against its Hi and Lo alarm setpoints.



High

Alarm

Low

Deadband

Normal

Alarm

Normal

150.0

138.0

72.0

60.0

LookoutDirect generates an alarm the moment the value violates the Hi or Lo alarm setpoints. The alarm returns to normal when the value drops below the high alarm setpoint minus the Deadband, or goes above the low alarm setpoint plus the Deadband. The Deadband also applies to all HiHi and LoLo alarm limit setpoints.

The Log to historical database parameters define how long to store a value in the Citadel database on your hard drive. If you do not select this option,

LookoutDirect does not log the value to your disk. If any scaling or filtering parameters are defined, LookoutDirect logs the scaled, filtered value (that is, the engineering unit value).

Tip

If you intend to display data with a LookoutDirect Hypertrend object, you must log the data to the historical database.

When you log data, it will go to the database directory you set up in the

Create Process dialog box.

See Chapter 7, Logging Data and Events, in the LookoutDirect Developer’s

Manual for more information on logging data.

Logical Member Parameters

Some of the parameters of logical data members are different from those of numeric data members. Scaling of a logical signal consists of the Invert

Logical Signal checkbox. When you choose this checkbox, an ON value is represented by an OFF value, and so on. When you do not select it, ON is ON and OFF is OFF.




A logical database is shown being configured in the following figure.

Alarm parameters of a logical signal include the alarm Area assignment field and the Generate Logical Alarm checkbox. When selected, the data member generates an alarm whenever the value is ON; the alarm condition clears whenever the value is OFF. Notice that if the Invert Logical Signal checkbox is selected, the value used here is the inverted value. See Chapter 9, Alarms, in the LookoutDirect Developer’s Manual for more information about alarms.

Text Member Parameters

The text data member database contains only Alias, Member, and

Description fields. You can log text data to the database, but the only way to query for the logged text string is though the LookoutDirect SQLExec object.



Importing and Exporting Object Databases

Use the import database service to copy database member parameters from an

Excel spreadsheet file directly into an object. Use the export database service to copy an object database into an Excel spreadsheet file. This is what you can do using these services:

• Export object database parameter definitions to Excel for the purpose of documentation.

• Export an object database to Excel, perform global replacements on data member parameters, and then import the changes.

• Create a name list in Excel or in an application that exports to Excel, then copy that name list into LookoutDirect.

• In a process using multiple duplicate driver objects (such as a gas pipeline or water distribution system), define a single driver object database parameters in Excel. Import that database into multiple driver objects.

Although you can import and export any object database, you may find that these services are most useful for objects with large native databases, such as driver objects and Data Table objects.

Exporting an Object Database

Follow these steps to export an object database:

1.

Open the Edit Database dialog box, either through the menu or the

Object Explorer, choosing the object you want to export from.

The following diagram shows a Modbus object that already has a number of logical and numeric data members defined.




2.

In the database dialog box, click on the Export button.


3.

In the Export Object Database to dialog box, choose a directory path, enter a filename and click on OK.

When you export a database, LookoutDirect does not export every possible data member (many driver objects have a capacity for thousands of members). Instead, LookoutDirect exports configured points; that is, data members that have at least one parameter already defined. LookoutDirect also exports native members that are in use (that is, connected to other objects).



The spreadsheet file that the LookoutDirect Export command creates is in

Excel Version 2.0 format. An example of the

.xls

file is shown in the following illustration.

Creating a Database Spreadsheet

The easiest way to create a database spreadsheet for an object is to create the object in LookoutDirect, define the parameters for one logical data member, one numeric data member, and one text member (if necessary). You then export the database to a spreadsheet file.

This creates a basic spreadsheet file with all the necessary column labels for

LookoutDirect to read. The three data members you edited in LookoutDirect furnish examples you can follow to rapidly create or edit more data members of the same type, using the convenient tools of your spreadsheet program.

Notice the figure above, that row 1 contains column labels. These include the names of all possible data member parameters. LookoutDirect references the labels of a spreadsheet file, not the column letters, so if you were to create a spreadsheet to import into LookoutDirect manually, you would have to spell all column labels correctly. LookoutDirect ignores white space and is case-insensitive. The following list contains all possible column labels, in the order in which LookoutDirect inserts them when creating a spreadsheet file.

• Command

• Member

• Alias

• Description

• Prefix

• Suffix

• Eng min

• Eng max

• Raw min




• Raw max

• Invert?

• Deviation

• Force?

• Forced value

• Alarm area

• Lolo level

• Lolo priority

• Lo level

• Lo priority

• Hi level

• Hi priority

• Hihi level

• Hihi priority

• Logical priority

• Log data?

• Lifespan

LookoutDirect requires the column labels Command and Member. All other column labels are optional. Command must be in cell A1. The order in which the other column labels appear makes no difference.

Any time you import a database, LookoutDirect reads the first 30 columns

(A–AD) and ignores columns that do not have labels.

The rows below the column labels (below row 1) each represent a database data member. For example, row 5 in the spreadsheet in the previous figure represents the data member whose alias name is

FIC101Mode

.

You can easily add rows to define new data members. Copy the rows associated with FIC101, for example, and then modify the new rows slightly by identifying different native members and giving them new aliases and descriptions.

After you have edited and expanded your spreadsheet file, you can save it and import the new values back into LookoutDirect, adding all the new data members to those your configured earlier as template samples.

If you are working with a version of Excel more recent that 4.0, the program asks you if you want to update your spreadsheet to a newer format when you



select File»Save. This dialog box is shown in the following illustration . Be

sure to select No. LookoutDirect does not currently accept Excel spreadsheet files from versions greater than 4.0.

Importing an Object Database

Editing a spreadsheet file for several similar data members, and then importing it as an object database, can be much faster than working in the

LookoutDirect dialog boxes one at a time. When you import a database,

LookoutDirect reads the first 30 columns (A–AD) It ignores columns that do not have labels and columns beyond AD.

Each row in the Command column (column A) contains either the keyword insert

or the keyword delete

. When you import a database,

LookoutDirect ignores rows that do not have the insert

or delete keyword. It adds those records whose command keyword is insert

. It removes those records whose command keyword is delete

. To determine exactly which records to delete, LookoutDirect uses the record alias name; or if the record does not have an alias name, it matches the record member name.




Follow these steps to import an object database:

1.

Open the Edit Database dialog box, either through the menu or the

Object Explorer, choosing the object you want to import from.

2.

In the object database dialog box, click on the Import button.

3.

In the Import Object Database from dialog box, choose a directory path, select the filename and click on OK.

When finished, LookoutDirect presents you with a set of database import statistics, as shown in the following illustration.



As you can see in the following figure, the data members added to the database spreadsheet were successfully added to the Configured points list.

Copying an Object Database

The import and export features make it easy to copy the database of an object.

This is especially useful when creating large SCADA applications, such as gas pipelines with multiple compressor stations.

The key to defining multiple driver objects that require duplicate databases is to first create an object in LookoutDirect for each RTU or PLC. Then create a single database in Excel. Next, import that database into each driver object.





Glossary

Prefix

mk-

M-

A

absolute date absolute time

Meanings

millikilomega-

Value

10

– 3

10 3

10 6

ACK active notification address space alarm alias

Numeric system LookoutDirect uses for keeping track of dates and times, in which midnight (0 hours), January 1, 1900 is represented by 1, midnight of January 2, 1900 is represented by 2, and so on. The absolute date/time number 36234.47222250 represents 11:20 A.M., March 15, 1999.

The numeric value for 1 second in LookoutDirect is .000011574, the numeric value for 1 minute is .000694444, and the numeric value for 1 hour is .041666667.

Acknowledge (an alarm or event).

A feature of event-driven software systems in which the application is alerted of value changes when they occur instead of through continuous, loop-driven queries.

An OPC term for the area you browse to find what items are available on an OPC server. Part of the standard OPC interface, this space may arrange items hierarchically.

Software notification of a condition in a process. This alarm may call attention to a value that has exceeded or fallen below certain levels, set in the object database or in an Alarm object.

Name given to a data member using the Edit Database dialog box. This name can be descriptive or mnemonic, and can be associated with other data member configurations such as scaling, logging, and alarming. A data member can have more than one alias, each with different associated configurations.


G-1 Developer’s Manual

Glossary

B

baud rate

.bmp files bps

C

CBL compiler

.cbx file checksum

Citadel classes client

Measurement of data transmission speed, formally defined as the number of electronic state changes per second. Because most modems transmit four bits of data per change of state, is sometimes misused or misunderstood—a 300 baud modem is moving 1200 bits per second.

See bps.

Graphic files in bitmap format. If you are using a

.BMP

file in

LookoutDirect, you cannot resize it on screen. See Windows metafile.

Bits per second—measure of the rate of transfer of data. comm port connection control objects controllable objects


LookoutDirect uses the CBL (Control Block Language) compiler to compile a LookoutDirect source file (

.lks

) into a binary file (

.l4p

).

A LookoutDirect file containing a LookoutDirect object class. A

.CBX

(Control Block Extension) file can have one or more object classes in it.

A method of verifying that the number of bits received is the same as the number of bits transmitted. Used by TCP/IP and serial protocols.

The LookoutDirect historical database that stores your data for access later.

See object classes.

A LookoutDirect process that monitors a LookoutDirect server process.

LookoutDirect clients should be computer independent so that they can be run from any computer on your network. LookoutDirect server processes run on computers actually connected to your control hardware.

Term sometimes used for a serial port.

Input to a LookoutDirect object’s writable data members. For more information, refer to Chapter 4, Using LookoutDirect, in your Getting

Started with LookoutDirect manual.

LookoutDirect objects you use to control a process, change a data value, adjust a register, and so on.

LookoutDirect objects you can control with a LookoutDirect control object.

G-2 www.Automationdirect.com

.csv files

CTS cursor (data table)

Glossary

Comma Separated Value file, a format widely accepted by spreadsheet and other data handling programs.

Clear to Send. Part of a handshaking protocol for certain devices that connect the serial port of a computer. See the RTS/CTS Handshaking

Settings section of Chapter 3, Serial Port Communication Service, for detailed information.

The LookoutDirect data table can activate one row of data at a time using the data table cursor. See the Data Table reference in the online help or the

LookoutDirect Object Reference Manual.

D

DAQ data member data type database datagram

DCOM/COM

DDE

Short for Data AcQuisition.

Data source or sink associated with a LookoutDirect object. A readable data member, or source, can be used in expressions or as inputs to other objects. A writable data member, or sink, can have at most one connection into it, created using the Object»Edit Connections dialog box. A data member can be both readable and writable.

See also native data member and alias.

Kind of value (numeric, logical, or text) that a parameter or data member can hold.

Collection of data stored for later retrieval, display, or analysis.

Message sent between objects in LookoutDirect. A datagram contains a route and a value.

Distributed Component Object Model, a Microsoft standard in which client program objects request services from server program objects.

The Component Object Model (COM) is a set of interfaces, clients, and servers used to communicate within the same computer (running

Windows 98/95 or Windows NT).

Dynamic Data Exchange, currently used in LookoutDirect to exchange data with other programs (such as Microsoft Excel) running on your network.



Glossary

deadband deviation dialing prefix displayable objects

DLL driver objects

A value that must be exceeded for an alarm to sound or a change in state to be recorded. For instance, if you have a low-level alarm set at 5 with a deadband of 2, the alarm will not trigger until the value being monitored drops to 5. The alarm will then stay active until the value being monitored moves above 7. A deadband keeps small oscillations of value from triggering an alarm and then canceling it too rapidly.

Set a deviation to filter out small changes in value when logging data.

Before being logged to a database, a value must change by at least the deviation amount of the last logged value.

Part of the Hayes AT command set for use with modems. See the Dial-Up

Modem Settings section of Chapter 3, Serial Port Communication Service, for detailed information.

A LookoutDirect object class that has a displayable component, such as a

Pot, a Switch, or a Pushbutton.

Dynamic Link Library, which is a collection of small, special-purpose programs which can be called by a larger program running on the computer. Sometimes called Dynamically Linked Library.

LookouDirect objects used to communicate with PLCs, RTUs, and other

I/O devices.

E

edit mode engineering unit environment services

Ethernet

LookoutDirect mode in which you can alter and create objects within a process. Switch in and out of edit mode by pressing <Ctrl-space> or by selecting Edit»Edit Mode.

In LookoutDirect, used to refer to scaled or converted data. Thermocouple data, for instance, arrives in volts as the raw unit, and must be converted to degrees, an engineering unit.

Tasks LookoutDirect performs as a part of making your SCADA/HMI work easier. LookoutDirect environment services include serial communications, database and logging, security, networking, alarming, and so on.

A widely used, standardized local area networking technology, specified in the IEEE 802.3 standard.

Developer’s Manual G-4 www.Automationdirect.com

event expression functions expressions

Glossary

Anything that happens can be an event. In LookoutDirect, events include such things as adjusting a control value, entering or exiting edit mode, opening or closing a control panel, and logging in or logging out of the system.

Mathematical, logical, and other functions used by LookoutDirect expressions.

LookoutDirect expressions are often paths to a data member. They can also function like variables that, using a spreadsheet cell-type formula, become capable of performing flexible, real-time math operations, condition testing, and other complex operations functions. See Chapter 1,

Expressions, for more information on expressions.

F

failover

FieldBus

FieldPoint frame functionality functions

A failover is the takeover of a process by a standby computer when the primary computer fails for any reason.

An all-digital communication network used to connect process instrumentation and control systems.

A National Instruments hardware product line for industrial automation, control, monitoring, and reporting.

Sequence of bytes sent from a computer to a device or vice versa. The syntax of the frame depends on the protocol being used. A read frame contains enough information to specify a set of variables whose values the device should return. A write frame specifies a variable in the device and a new value to write into that variable. Some protocols support the writing of multiple variables in a single frame. A response frame is returned from the device to the computer, indicating whether the frame just sent to it was received successfully. If the frame just received was a read frame, the response frame contains a set of requested values.

The way an object works, operates, or performs a task. Functionality is a general concept that applies in the same way to all objects in a given object class. Parameters define the specific functionality of an individual object.

See expression functions.



Glossary

G

gray proximity A term used in LookoutDirect color animation. This sets what percentage of gray will be replaced by a given color as conditions change in a monitored value or set of values.

H

Hi and HiHi historical logging

HOA

Alarm settings. Both warn that a value has gone above some setpoint.

Generally a Hi alarm is used to alert an operator of a need for intervention.

A HiHi alarm is usually used to alert an operator that the value has been exceeded by an even greater margin than a Hi alarm indicates, and is usually used to indicate an urgent need for action.

The process of storing data in a database for use at another time, or from another location.

Hand-Off-Auto control, used to set whether a value must be changed manually, is completely turned off, or functions automatically. You can use a Pot object and a complex expression to create this sort of control in

LookoutDirect, or you can use a RadioButton object, depending on the particular requirements of the task you need to accomplish.

I

I/O point

(implicit) data member

Every read-only, write-only, or read-write connection LookoutDirect makes to external hardware is counted as an I/O point. LookoutDirect is licensed for use with a set number of I/O points. If you exceed the number you are licensed to use with your copy of LookoutDirect, a warning message appears on your computer screen warning you to shut down one of your processes within a specified time before LookoutDirect cuts back on I/O usage.

A LookoutDirect data member containing the fundamental data for certain object classes. When you make a connection to an (implicit) data member, you only use the name of the object, not the name of the object followed by the data member name.


Glossary

L

.l4p files

.l4t files

.lka files

.lkp files

.lks files logging logical data member

.lst files

File extension for LookoutDirect process files. These are the compiled files LookoutDirect runs when it runs a process.

File extension for a LookoutDirect state file, which stores the values for

LookoutDirect controls and other objects with state information.

File extension for LookoutDirect security files.

File extension for LookoutDirect process files in versions of

LookoutDirect earlier than LookoutDirect 4.

File extension for a LookoutDirect source file, which LookoutDirect compiles to make a LookoutDirect process file that LookoutDirect can run. This is the file you should make sure you keep backed up in case you need to recreate a corrupted process file, or in case some future version of

LookoutDirect cannot run a process file compiled in an earlier version of

LookoutDirect.

The process of storing data in a computer database file. See Chapter 7,

Logging Data and Events, for more information on logging data in

LookoutDirect.

A LookoutDirect data member of the logical data type.

Extension for the LookoutDirect state file in versions of LookoutDirect earlier than LookoutDirect 4.

M

multiplex A method of working with more than one data stream using only one communications channel. There are a number of different methods of multiplexing, depending on the hardware and software being used. A number of LookoutDirect driver objects support multiplexing hardware.



Glossary

N

native data member

NetDDE numeric data member

O

object object classes object connections

ODBC

OPC

Data members built into a LookoutDirect object class, as opposed to data members you create by using aliases.

A way of networking using DDE (dynamic data exchange), retained in

LookoutDirect 4 for compatibility with earlier versions of LookoutDirect.

A LookoutDirect data member of the numeric data type.

A specific instance created from an object class.

Software modules you use to create individual objects to perform tasks in

LookoutDirect.

Software links between objects used to transmit data and commands from one object to another.

Open DataBase Connectivity, a standard application programming interface (API) for accessing a database. You can use ODBC statements to access files in a number of different databases, including Access, dBase,

DB2, and Excel.

ODBC is compatible with the Structured Query Language (SQL)

Call-Level Interface. ODBC handles SQL requests by converting them into requests an ODBC database can use.

OLE for Process Control, an industry standard interface providing interoperability between disparate field devices, automation/control systems, and business systems. Based on ActiveX, OLE, Component

Object Model (COM), and Distributed COM (DCOM) technologies.

P

parameter ping

Input to an object, similar to a writable data member, whose value is specified in the object parameter list in a LookoutDirect source (

.LKS

) file. Typically, parameter values are set in the object Object»Create or

Object»Modify dialog box.

A small utility program in Windows and DOS that checks to see if a computer can be reached across a network. Also used to indicate the running of that program.


pixel

PLC poll poll rate pop-up panel process process file

Glossary

Picture Element, the smallest bit of a picture. Has one color or shade of grey. The number of pixels per inch determine the resolution of an image.

Programmable Logic Controller.

A software event in which a computer checks some value in a device or register. In LookoutDirect, a logical command that forces a device poll to check data member values.

How often a device is polled.

One variety of LookoutDirect control panel that can only be displayed at the size set by the process developer, and which cannot be maximized.

When open, a popup panel remains on top of other panels until minimized.

In LookoutDirect, process refers to a LookoutDirect “program”, used for industrial automation, control, monitoring, or reporting.

The LookoutDirect binary file LookoutDirect executes when running a process. Carries the

.l4p

extension.

R

raw unit receive gap redundancy remote resolution


Data as it arrives in your process, such as voltage or amperage.

Thermocouple data, for instance, arrives in volts as the raw unit, and must be converted to degrees, an engineering unit.

A serial communications setting that determines the number of empty bytes (or amount of time) a driver receives before recognizing the end of a message frame and requesting another message. See the Setting Receive

Gap section of Chapter 3, Serial Port Communication Service, for more information about the receive gap.

A system for making sure that a computer can come online and run a

LookoutDirect process if the computer currently running that process fails for some reason.

In the context of LookoutDirect, remote is a position source location for a control. See the Remote Position Source section of Chapter 4, Using

LookoutDirect, in the Getting Started with LookoutDirect manual for detailed information on the LookoutDirect remote position source.

The smallest signal increment that can be detected by a measurement system. Also, the number of pixels per inch on a computer monitor screen or dots per inch in printer output.


Glossary

RTS

RTU run mode

Request to Send, part of a handshaking protocol for certain devices that connect the serial port of a computer. See the RTS/CTS Handshaking

Settings section of Chapter 3, Serial Port Communication Service, for detailed information.

Remote Terminal Unit, a device similar to a PLC for use at a remote location, communicating with a host system through radio or telephonic connections.

LookoutDirect mode in which processes run but no editing changes can be made. Switch in and out of run mode by pressing <Ctrl-space> or selecting

Edit»Edit Mode.

source file

SQL standby startup file state file

S

SCXI security accounts server


Signal Conditioning eXtensions for Instrumentation, a National

Instruments product line for conditioning low-level signals.

Also called user and group accounts, LookoutDirect uses security accounts to define what users or group of users have different operation privileges in LookoutDirect. See Chapter 6, Security, for detailed information on LookoutDirect security.

A process that provides data (services) to client processes. In

LookoutDirect, server processes are intended to be run on one computer only, with direct connections to field hardware. Client processes interact with field hardware through server processes.

LookouDirectt file that can be compiled to produce a binary

LookoutDirect process file that runs a process. Uses a

.lks

file extension.

Structured Query Language, used to get information from and update information in a database.

A computer standing by to take over running a process if the primary computer fails or falls offline.

A LookoutDirect process file (

.l4p

) you designate in the System

Options dialog box that LookoutDirect will open and run any time

LookoutDirect is opened.

The LookoutDirect file that stores the value of all LookoutDirect control parameters and object data members in use in a process. Uses the file extension

.l4t

.

G-10 www.Automationdirect.com

system objects

T

TCP

TCP/IP

Glossary

LookoutDirect objects used to control other objects or process and analyze data.

text data member trace traces table trend

W

.wav files

Windows metafile

Transmission Control Protocol, a method (protocol) for sending data between computers. Used with IP, the Internet Protocol.

TCP/IP sends data as packets, with IP handling the delivery of data and

TCP keeping track of the individual packets.

LookoutDirect data member used for text data.

A term for data from a single source over some period of time, stored in an ODBC-compliant database.

ODBC databases present data in the form of traces tables. A traces table contains a field or column of data for each data member being logged, along with a field you can use to query the database.

Historical data showing the change in a value over time. Often used in connection with graphing the data for display.

.wmf files

X

.xls files

File extension given to sound files. You can play a

.wav

file in

LookoutDirect to add sounds or speech to alarms or events.

A standard graphics file type for use in the Microsoft Windows operating environment. If you use a metafile graphic in LookoutDirect, you can enlarge or reduce it on the screen, use them as masks without specifying transparent pixels, and use the LookoutDirect Animator to animate the colors of the graphic.

File extension given to Windows Metafile graphic files.

File extension given to Microsoft Excel files.



Glossary


A

Networking With DDE


This appendix explains how to network LookoutDirect using DDE. This information is retained in LookoutDirect 4 for compatibility with earlier versions of LookoutDirect.

While in LookoutDirect 4 you can do most process networking with the faster and more efficient TCP/IP, you might want to use DDE to communicate with other applications, such as Microsoft Excel (as described in Chapter 5,

Dynamic Data Exchange).

You can use LookoutDirect DDE networking capabilities to do the following:

• View the same or different screens simultaneously on separate nodes

• Make setpoint adjustments from any node

• Acknowledge alarms from any node

• Configure specific nodes for monitoring only

• Configure a peer-to-peer architecture

• Configure a client-server architecture

• Configure network nodes to communicate through standard telephone lines

• Configure network nodes to communicate through radios

Networking multiple LookoutDirect nodes is a powerful and advanced capability. This appendix refers to many concepts and terms explained elsewhere in the manual. Before you attempt to work with networking, make sure you have a strong understanding of the LookoutDirect architecture and are comfortable working within LookoutDirect on a single node.

To network using LookoutDirect, you must meet the following requirements:

• Purchase and install on each computer a separate, licensed copy of

LookoutDirect.

• Equip each computer on the network with compatible network hardware.

• Install Microsoft Windows NT/98/95 on each computer.

Because LookoutDirect is a native Windows application, it supports all the networks that Microsoft Windows supports, including Microsoft Windows

A-1 Developer’s Manual

Appendix A

Network, Microsoft LAN Server, Novell NetWare, Banyan VINES,

3Com 3+Open, DEC Pathworks, IBM LANServer, and so on.

NetDDE Networking Considerations

Networking with LookoutDirect involves passing data back and forth between two or more LookoutDirect nodes. In LookoutDirect, data is passed between and contained within objects. There are two basic methods for passing data between multiple LookoutDirect nodes: Multilink Networking, which requires a NetDDE (Network Dynamic Data Exchange) link for every value being passed between the nodes, and Table Networking, which implements a data concentrator at each node where only tables (which concentrate the data) are linked between nodes. Although both methods involve connecting objects over a network using NetDDE, the implementation and total effect can be quite different.

If you plan to use one of the NetDDE methods, you have to configure automatic NetDDE activation and possibly trusted DDE shares. See the

Running NETDDE.EXE Automatically and Adding a Trusted DDE Share sections in this appendix for setup instructions.

There is one more method for implementing network-like capabilities between multiple LookoutDirect nodes. Unlike the first two methods, however, this technique does not rely on data being passed between

LookoutDirect nodes. Instead, you use PLCs, RTUs, or I/O to share data between LookoutDirect nodes. This method is called Hardware Networking.

Developer’s Manual A-2 www.Automationdirect.com

Appendix A

Multilink NetDDE Networking

Multilink networking consists of passing data from an object on one computer to another object on a different computer. When linked, any change to the value of one object is instantly propagated to and reflected by the second object on the other computer. The way in which data is passed between two objects across a network depends on whether they are controllable objects.

Linking Controllable Objects

User-controlled objects have a DDE option. These objects include Pot objects, Switch objects, and Pushbutton objects.

Controllable objects each have three Position source options: Local,

Remote, and DDE. When you choose DDE, you instruct the object to take its value from a remote source. This could be a cell in a spreadsheet, another

DDE-aware application, or a second copy of LookoutDirect running on the network.

Linking Controllable Objects Together Across a Network

You need at least two computers connected by a functioning network to use the following example. This example refers to the two computers as

Station1 and Station2.

1.

At Station1, create a Switch object called

Switch1

. Leave Position

source at the default setting of Local.

2.

At Station2, create a corresponding Switch object called

Switch1

.

However, change the Position source to DDE. (Although you are not required to give objects matching names over a network, it makes your documentation easier to follow and your applications easier to maintain.)


3.

In Service, enter

\\Station1\NDDE$

, where

Station1

is the network name of the other computer. The backslashes,

NDDE

, and dollar sign are required by Microsoft Windows.


Appendix A

4.

In Topic, enter

Filename$

, where

Filename

is the name of the

LookoutDirect process file on the other computer.

Again, the dollar sign is required but the

.l4p

file extension is not.

5.

In Item, enter the name of the object at the other computer that you want to link to (in this case, the other object is also called

Switch1

).

6.

Click on OK.

Test your network by flipping the switch. When you toggle the switch at either station, it instantly flips at the other workstation. You can add to, modify, delete, or revise your logic on either computer, completely on-line, and still maintain the network link between the two objects.

Linking Non-Controllable Objects

If a LookoutDirect object is not a Pot, Switch, or Pushbutton, it probably does not have built-in DDE capabilities. However, all you are really trying to do is pass data between two computers. After the data is in LookoutDirect, any object can access it, so you can create a DdeLink object to receive data from another application using DDE or NetDDE. For more information, refer to the discussion of the DdeLink object in the online PDF Object Reference Manual and online help. In this example, the other application is LookoutDirect running on a second computer.

To Access Real-Time Data at Another Computer

You need at least two computers connected by a functioning network to follow this example. This example refers to the two computers as Station1 and Station2.

1.

At Station1, create an Average object. It can average whatever values you want, but give it the name

Average1

.

2.

At Station2, create a DdeLink object and name it

Average1

. Although you are not required to give objects matching names over a network, it makes your applications easier to maintain.


Appendix A

3.

In Service, enter

\\Station1\NDDE$

, where

Station1

is the network name of the other computer. The backslashes,

NDDE

, and dollar sign are required by Microsoft Windows.

4.

In Topic, enter

Filename$

, where

Filename

is the name of the

LookoutDirect process file on the other computer.

Again, the dollar sign is required but the

.l4p

file extension is not.

5.

Enter the name of the object at the other computer that you want to link to in the Item field (in this case, it is also called

Average1

).

6.

Click on OK.

7.

Finish the definition of the DdeLink object by inserting the DDE expression into your panel.

After you establish the link, you can connect other objects at Station2 to the

Average1

DdeLink object. Remember, just because you named the

DdeLink object

Average1

does not make it a LookoutDirect Average object.

It just receives data from the Average object at Station1.



Appendix A

Table Networking

Table networking consists of consolidating all the data that needs to be shared over the network in a single table or array of values. You might think of these tables as “data concentrators”—although they can do much more than just serve as a repository for data. For more information, refer to the discussion of the DataTable object in the online PDF Object Reference Manual or the online help. You can link a table through NetDDE to a corresponding table on another computer. When linked, the tables update each other on all changes within their databases.

Note

Table networking is one of the most involved and advanced concepts in

LookoutDirect. You should have a complete understanding of objects, database connections, events, and general LookoutDirect architecture before you attempt table networking.

Node 1 Node 2

Object 1

Object 2

Object 1

Object 2

Table

DDE Link between

“Data Concentrators”

Table

Object 3

Object 4

Object 3

Object 4

You might have better results linking multiple DataTables for networking purposes if you plan before jumping headfirst into your application. The following example shows how table networking is done.

This example consists of three computers, each running a copy of

LookoutDirect. Set up three nodes on the network with the names Station1,

Station2, and Station3. Station1 is the only node directly connected to a PLC, but you want to monitor and control the I/O from any of the three nodes. The following diagram depicts the network structure of this example.



PLC PLC PLC

Proprietary Network

PLC

Appendix A

Lookout Lookout Lookout


Station 1 Station 2

Local Area Network

Station 3

By doing a little planning, you can configure LookoutDirect at Station1 so that you can reuse its process file at Station2 and Station3. The following diagram depicts the general design of the LookoutDirect process file at

Station1. Notice that Driver objects are connected to the DataTable object using dotted lines while all other objects are connected using solid lines. This is for illustrative purposes only.

Station 1

Driver

Object

(Other)

Object

Driver

Object

(Other)

Object

DataTable

Object

(Other)

Object

Driver

Object

(Other)

Object

Driver

Object

The focus of this picture is the Driver objects and their connections to the

DataTable. Eventually, you will modify this process file to run at Station2 and


Appendix A

Station3 by deleting all connections to Driver objects, then deleting the

Driver objects themselves at Stations 2 and 3.

It is important to route all signals to and from Driver objects through the

DataTable. If you want to display an analog input from a PLC on a control panel, do not connect the PLC signal directly to the control panel. Instead, first connect it to the DataTable and then connect the appropriate DataTable cell to the control panel. If you need to connect an operator setpoint to an output on a PLC, do not connect the setpoint directly to the PLC. First connect the setpoint to the DataTable, then connect the appropriate DataTable cell to the output on your PLC. This is only necessary for signals that originate from, or are destined for, a Driver object. Although this procedure adds another step to your LookoutDirect configuration for Station1, it greatly simplifies the development of the process files for Station2 and Station3.

Now that you have developed an application at Station1, move over to

Station2. Copy the process file to the Station2 computer and delete all the connections to and from your Driver objects. Then, delete the Driver objects themselves.

Remember, you do not want Station2 attempting to communicate with the

PLCs because there is no physical connection to that proprietary network.

Station2 should get its information from Station1.

The only thing left to do is modify the DataTable object at Station2.

Change its Table location parameter to DDE. In Service, enter

\\Station1\NDDE$

. In Topic, enter

Filename$

, where

Filename

is the name of the process file at Station1. In Item, enter the name of the

DataTable object at Station1. Your DataTables are now bidirectionally connected through a NetDDE link.

At this stage, you can add more operator stations to the network. Copy the process file from Station2 to Station3, or to any number of other

LookoutDirect nodes on the network. No changes to the files themselves are necessary.

Your LookoutDirect network topography should now look something like this.


Appendix A

Station 1

Driver

Object

(Other)

Object

Driver

Object

(Other)

Object

DataTable

Object

(Other)

Object

Driver

Object

(Other)

Object

Driver

Object

Station 2

(Other)

Object

(Other)

Object

DataTable

Object

(Other)

Object

(Other)

Object

NetDDE

Connections

Station 3

(Other)

Object

(Other)

Object

DataTable

Object

(Other)

Object

(Other)

Object



Appendix A

Hardware Networking

In general, you should try to avoid hardware networking as described here with LookoutDirect 4. To implement the hardware networking method, all

LookoutDirect nodes you want networked must have direct communication access to all your hardware as displayed in the following diagram. Because of this, the hardware networking method is only applicable in certain circumstances.


PLC PLC PLC PLC

Lookout Lookout Lookout

Station 1 Station 2 Station 3

This is the most straightforward of the three networking methods to implement. Configure a process file at one node and copy it to all other nodes that have direct communication access to your hardware. The only thing to remember when building your process file is to configure all Pots, Switches, and Pushbuttons with the Remote parameter setting. This ensures that they stay in sync with the point they are writing to. In other words, if a switch at one LookoutDirect node changes the status of an output, all the respective switches at the other LookoutDirect nodes will reflect the change and automatically flip to stay in sync. For more information on the Remote parameter, refer to the Pot, Switch, and Pushbutton descriptions in the online

PDF LookoutDirect Object Reference Manual in the online help.

Your hardware, network, and communications topology are the determining factors on whether you can use hardware networking. The hardware networking method is seldom available because it is rare that all your

LookoutDirect nodes can communicate directly with all your hardware.


Appendix A

Multilink and Table Networking Comparison

There are advantages and disadvantages to both multilink and table networking. Multilink is quick and easy for small jobs. However, every

NetDDE link requires processor time, so the more links you have, the more

CPU overhead is used. Remember, each value passed between computers requires a separate DdeLink object. Your computer can quickly become bogged down if hundreds of links are constantly sending values back and forth.

On the other hand, while the table method might require more initial planning and development time, there will be only one NetDDE link between computers connecting the DataTables. This method dramatically reduces the amount of DDE traffic on the network. That is why table networking is the method of choice for large systems where computers are sharing hundreds or thousands of values across the network.

So how many points are too many? There is no single answer, but

LookoutDirect has been used with the table networking method on systems having over 6000 values, and the network update time is well under one second with only three percent CPU usage.



Appendix A

Setting up Networking with DDE

LookoutDirect uses Network DDE (Dynamic Data Exchange) for client/server networking.

Two components of Microsoft Windows are required when using Network

DDE: the Network DDE agent (

NETDDE.EXE

) and the NetDDE Share

Database Manager (DSDM). Exactly how these components are used depends on the operating system on which LookoutDirect runs:

Windows 98/95 or Windows NT.

The program

NETDDE.EXE

is an agent that runs in the background and transfers DDE messages between computers. This program should be running before an instance of LookoutDirect is started if you intend for that session to act as a server. LookoutDirect does not automatically run

NETDDE.EXE

itself.

Running NETDDE.EXE Automatically

The following sections show how to make sure that

NETDDE.EXE

runs every time you start Windows.

Windows 98/95

1.

In Windows 98/95, Click Start»Settings»Taskbar.

2.

In the Taskbar Properties dialog box, choose the Start Menu

Programs tab.

3.

Click on the Add button.

4.

In the Command line field of the Create Shortcut dialog box, enter

NETDDE.EXE

, then click Next.

5.

Choose the Start Menu»Programs»StartUp folder, then click Next.

6.

Select a name (such as

NetDDE

) for the shortcut; select Finish and OK.

Windows NT

1.

In the Program Manager, double-click on the Control Panel icon, or run

CONTROL.EXE

using the Program Manager File»Run dialog box. If you are using NT version 4.0, click on Start, point to Settings, and choose the Control Panel.

2.

In the Control Panel window, double-click on the Services icon.

3.

From the list of services, select

Network DDE

.

4.

Click on the Startup button.

5.

In the Startup Type box, select

Automatic

.


Appendix A

6.

Select OK and Close to exit the Control Panel.

Adding a Trusted DDE Share

To allow someone else to connect to a DDE share (for example, process$

) on your computer when you are logged in, you must trust the DDE share.

When other users connect to the share remotely, the application they connect to is running in your security context because you are the logged-on user. You must give permission for the other users to access the share. Even another person who is an administrator cannot trust a share for your account.

In Windows 98/95, trusted shares are automatically created by

LookoutDirect.

In Windows NT, you must use the program

DDESHARE.EXE

to add a trusted share. Exactly how you set this up depends on the level of security you require. The following sequence of steps describes how to set up a share that gives everyone on the network full DDE access to LookoutDirect.

1.

From the Program Manager, select File»Run. If you are using

Windows NT version 4.0, click Start and select Run.

2.

Enter

DDESHARE.EXE

.

3.

Select Shares»DDE Shares.

4.

In the DDE Shares dialog box, select Add a Share.

5.

In the DDE Share Properties dialog box, do the following: a.

For the Share Name, enter the name of the LookoutDirect process file that you want to share, omitting the

.LKP

extension, and adding a ‘

$

’ at the end. For example, if your process file was

PROCESS.LKP

, you would enter

PROCESS$ on this line.

b.

For the Static Application Name, enter LookoutDirect.

c.

For the Static Topic Name, enter the process file without extension, such as

PROCESS

.

d.

Leave the Allow start application and is service boxes unchecked.

e.

In the Item Security box, select Grant access to all items.

f.

Click on the Permissions button.

g.

In the DDE Share Name Permissions dialog box, do the following:

• In the Names list, select

EVERYONE

. If there is no entry for

EVERYONE

, use the Add button and associated dialog box to create it.



Appendix A

• In the Type of Access box, select

Full Control

.

• Select OK.

h.

Select OK.

6.

You should now be back in the DDE Shares dialog box. Select the share you just created and click on the Trust Share button.

7.

In the Trusted Share Properties dialog box, select the Initiate to

Application Enable button, then click on OK.

8.

In the DDE Shares dialog box, click on OK.

9.

Exit the DDE Shares program.

Note

For the DDE share to be available, it must be trusted by the user currently logged in to the computer (using steps 6 through 9). Alternatively, the share can be provided as a service by selecting the Is service box in the DDE Share Properties dialog box. In this case, the share is always available to anyone listed in the DDE Share Name Permissions dialog box.

Note

When a LookoutDirect client tries to connect to a DDE server on a computer running

NT, it might query the user for a user name and password that are valid on the server computer. In this case, the user password should not be NULL, or the attempt to connect to the server will fail.


B

CBL Compiler


LookoutDirect automatically compiles source files when you open the

.lks

file instead of the

.L4P

file. There is always the possibility that an automatic compile might fail, so you can also use LookoutDirect’s CBL compiler to manually compile a LookoutDirect source file from a DOS command line.

If the source file has been corrupted, you can view the error file for compilation errors and either repair the source file or delete corrupted sections and rebuild your process from an intact foundation.

This appendix explains how to use the CBL command-line compiler to compile an .

lks

file into an .

l4p

file.

You can re-compile an

.lks

file in LookoutDirect by using File»Open and choosing LookoutDirect Source Files (

*.lks

) as the type of file to open.

When you save a process in LookoutDirect, LookoutDirect creates an

.l4p

file and an

.lks

file. The

.lks

file is a source code file that includes object definitions, names, I/O configuration, communications, control logic, control panel layout, and other parameters. All

.lks

files are standard ACSII text files that you can print or view in any text editor. The

.l4p

file is a compiled executable that contains complete configuration information for a particular process control application. An

.lks

file can be compiled into an

.l4p

file with the CBL compiler. You can also generate an

.lks

file by hand or modify an existing

.lks

file and use the compiler to produce an

.l4p

file.

CBL is a command-line compiler that takes three arguments: sourcefile, targetfile, and error log file. To use it, type the following at the command line in a DOS window, where

file

is the name of your file: cbl file.lks file.l4p file.err

This command compiles the

.lks

file into the

.l4p

file and writes any error messages into the error file. If file.err

is not included in the command line, errors will appear in the DOS window. If the compiler generates error messages, you need to debug your object or your

.lks

file.

You can directly edit your

.lks

file with any text editor. In general, if there is no simple repair to be made as indicated by an error message, you can often repair a file by deleting the problem object and recreating it in LookoutDirect.

B-1 Developer’s Manual

Appendix B

CBL Compiler Error Messages

You can use the

.err

file to track down compilation errors.

The error file records errors one error per line, with a number at the beginning of each error message. This number corresponds to the line number of your

.lks

file where this error was encountered. You can go to these line numbers on your

.lks

file to correct the errors before recompiling your

.lks

file.

Here is a partial list of the error messages that you might encounter and tips on what might be causing them and how they can be corrected.

Class not found: class_name

The

.lks

file referred to a class that LookoutDirect does not know about

(for which no corresponding

.cbx

file exists). It might be that the desired class name was spelled incorrectly, or it might be that the Lookout

.dat

file needs to be removed so that LookoutDirect loads the

.cbx

file that defines the class. For example, the line

Foo1 = new Foo (); will produce the error

Class not found: Foo

Not a member of object name: member_name

The name used is not recognized as a valid member name for the object. For example, the line

Pot1.fred = 3; produces the error error: Not a member of ’Pot1’: ’fred’

Member is not writable for class class name: member_name

The data member is read only. For example, the line

Modbus1.update = 3; produces the error error: Member is not writable for class ’Modbus’:

’update’

Name is not valid

The name is not valid. For example, the line

Foo@ = new Pot (0, 100, 1, yes, 0); produces the error error: Tag is not valid: Foo@

Developer’s Manual B-2 www.Automationdirect.com

Appendix B

Member is not readable for class class_name: member_name

The data member is write only. For example, the line

Modbus1.1 = Pot1.increment; produces the error error: Member is not readable for class ’Pot’:

’increment’


B-3 Developer’s Manual

Appendix B

Developer’s Manual B-4 www.Automationdirect.com

C

Lookout.INI File

[System]

Section

LookoutDirect configurations are contained in the Lookout

.INI

file, located in your main LookoutDirect directory.

While it is generally best to configure LookoutDirect through dialog box options, you can edit this file yourself with any standard text editor. The

.INI

file sections and entries are listed below.

The syntax for an

.INI

file setting is

Key=setting

, where

Key

represents the particular feature or function of LookoutDirect you want configured, and

setting

represents the configuration value or choice.

Table C-1 Lookout.INI File Sections, Keys, and Settings

Key

NoReloadOfCBXes

CategorizeClasses

VBuffer

VBufferSize

SmoothMoves

Setting

=0

CBXs are not reloaded automatically (default

)

=1

CBXs are reloaded automatically

=0

Classes are not categorized in the Object Create dialog box

=1

Classes are categorized in the

Object Create dialog box

(default)

=0 off-screen bitmap buffer inactive

=1 off-screen bitmap buffer active

(default)

=(width*height) of off-screen bitmap buffer

(default = 250000)

=0

SmoothMoves off (default)

=1

SmoothMoves on


C-1 Developer’s Manual

Appendix C

Table C-1 Lookout.INI File Sections, Keys, and Settings (Continued)

Section

[System] ( continued)

SuppressRedundantWri tes

Startup

Key

AskBeforeShutdown

MaxWavesQueued

VirginEval

Setting

=0

Skip "OK to abort current process?" message window on process exit

=1

View "OK to abort current process?" message window on process exit (default)

This setting pertains to remoted

Pots. It essentially halts a write (a sending out of a datagram from the

Pot) if the last value that the Pot received is the same value it was about to write out

=0

Do not suppress redundant writes from Pots (default)

=1

Suppress redundant writes from Pots

This integer value specifies how many wave files the PlayWave object can queue up (default=10)

This line is in the

Lookout

.ini

file that comes with an evaluation version of LookoutDirect. If the line is there and equal to a non-zero number, LookoutDirect checks for the following entries

VGAeval=vgaeval.lkp

SVGAeval=svgaeval.lkp

and copies the result into Startup based on the user’s screen resolution. If neither of these entries is there, nothing gets written to Startup.

Name of the startup process

Developer’s Manual C-2 www.Automationdirect.com

Appendix C


Section

[System] ( continued)

Key

SaveSource

AlwaysMaxed

NoTaskSwitch

NoMenuBar

NoCaptionBar

LimitPopups

PopupLimit

Setting

You can tell LookoutDirect to save or not save the

.LKS

(source) file

=0

Do not save

.LKS

file

=1

Save

.LKS

file (default)

Security levels that limit certain abilities. They correspond to what you see in the System Options dialog box.

(default = 0)

[Alarms]

LVirtualKeyboard

RVirtualKeyboard

Header

Group

How many popups can be visible at one time. The security level associated with this feature is

LimitPopups.

(default = 4)

(default = 0)

LVirtualKeyboard

determines if the virtual keyboard appears on a left and/or right mouse click.

(default = 0)

RVirtualKeyboard determines if the virtual keyboard appears on a left and/or right mouse click.

=0

Do not show column headers in alarm window

=1

Show column headers in alarm window (default)

=0

Do not show group info in alarm window

=1

Show group info in alarm window (default)



Appendix C


Section

[Alarms] ( continued)

ShowPriority

ShowTag

MostRecent

AllGroups

Audible

Priority

Key

OldAlarmsLimit

Setting

=0

Do not show priority in alarm window

=1

Show priority in alarm window (default)

=0

Do not show object name in alarm window

=1

Show object name in alarm window (default)

=0

Display all instances of multiple alarms (default)

=1

Display only one instance of multiple alarms

=0

Show alarms for specified groups only (default)

=1

Show alarms for all groups

=0

Give no audible notification of alarms

=1

Give audible notification

(beep) of alarms (default)

Filter out alarms displayed in the alarm window that are below this priority.

(default = 1)

How many old occurrences of the same alarm to display in the alarm window.

(default=0)


Appendix C


Section


Style

Key Setting

Display style for the alarm window.

(default = 1622)

=1620 top

=1621 bottom

=1622 floating

=1623 minimized

Lines fHeight

LogDevice

Number of lines that can be displayed in the alarm window.

(default = 3)

Font height of font in the alarm window.

(no default) fWeight

Font weight of font in the alarm window.

(no default) fItalic (no default)

=0 text in alarm window NOT italics

=1 text in alarm window italics

Which device to log alarms to.

(default="(none)")

"(none)"

"LPT1:"

"LPT2:"

"LPT3:"

"LPT4:"

"COM1:"

"COM2:"

"COM3:"

"COM4:"



Appendix C


Section


[Citadel] fFace

DatabasePath

DatabaseMachine

[COM1, COM2, COM3, … ] LineType

Key

CTSTimeOut

RTSDelayOff

ReceiveGap

Setting

Font name of font in the alarm window.

(no default)

Path to your Citadel database.

Name of the computer you set for your Citadel database.

Comm port configuration

=0 wired (default)

=1 dial-up

=2

RTS-CTS

How long (in ms) LookoutDirect waits after asserting RTS for a CTS before sending the frame.

(default = 100)

(minimum = 0)

(maximum = 1000)

How long (in ms) after

LookoutDirect has finished sending the frame LookoutDirect continues to assert RTS.

(minimum = 2)

(maximum = 2000)

How many empty bytes

LookoutDirect must receive before recognizing the end of a frame.

(default = 20)

(minimum = 0)

(maximum = 1000)

Lookout 3.8 and later default

=

20

Lookout 3.7 and earlier default

=

5


Appendix C

Section

[COM1, COM2, COM3, … ]

( continued)


Key

DTR_HangUp

DialSecs

Retries

AlarmPriority

HangUpSecs

Setting

Determines how LookoutDirect hangs up a modem

=0

Use +++ATEH to hang up modem

=1

Use DTR to hang up modem

(default)

Length of time LookoutDirect waits to receive a connect signal back from the modem it is calling.

The time period begins when

LookoutDirect first sends the local modem the dialing prefix command.

(default = 60)

(minimum = 20)

(maximum = 1200)

The number of times

LookoutDirect dials the specified phone number and attempts to connect to the modem at the other end of the line.

(default = 3)

(minimum = 1)

(maximum = 10)

Alarms associated with this comm port will have this alarm priority.

(default = 1)

(minimum = 1)

(maximum = 10)

Length of time LookoutDirect waits after hanging up before it sends the local modem the next dialing prefix signal.

(default = 2)

(minimum = 1)

(maximum = 10)



Appendix C

[DDE]

Section

[COM1, COM2, COM3, … ]

( continued)

[Database]


Key

DiagnosticFile

DialPrefix

AlarmPriority

MaxLatency

FullSendSeconds

DefService

Setting

Full path to a location where

LookoutDirect creates a log file recording all serial transactions on this comm port. If a file already exists at this location, it will be appended to. This file is ASCII text, and is primarily used to diagnose serial port communications problems. (no default)

After editing the

Lookout

.INI

file, reload your LookoutDirect process file to force LookoutDirect to reread the

.INI

file.

LookoutDirect sends these Hayes

AT commands before every use of the modem.

(default="ATX4MVEDT")

Priority of database alarms.

(default = 9)

(minimum = 1)

(maximum = 10)

How often (in minutes) database data gets flushed to disk.

(default = 10)

How often (in seconds) to update all DDE tables.

(minimum = 30)

Default service and topic parameters for all DDE connections.

(no defaults)


Appendix C

[Events]


Section

[DDE] ( continued)

[Alarm Reports]

DefTopic fWeight fItalic fHeight fFace

Units fWeight fItalic fHeight

Key Setting

Default service and topic parameters for all DDE connections.

(no defaults)

Weight of the font used when printing events.

(no default)

Italics of the font used when printing events.

(no default)

Height of the font used when printing events.

(no default)

Name of the font used when printing events.

(no default)

Height (in points) of the font used when printing events.

(default = 10)

Weight of the font used when printing alarms.

(no default)

Italics of the font used when printing alarms.

(no default)

Height of the font used when printing alarms.

(no default)



Appendix C

[Edit]

Section

[Alarm Reports]

( continued)

Table C-1 Lookout.INI File Sections, Keys, and Settings (Continued) fFace

Units

Position

Pixels

ShowGrid

GridSize

Key

SnapToGrid

Setting

Name of the font used when printing alarms.

(no default)

Height (in points) of the font used when printing alarms.

(default = 10)

Where the next created panel element appears relative to the currently selected panel element.

=309

=310 right (default) left

=311

=312

=313 top bottom center

How many pixels away in the direction selected by

Position

to create the next panel element.

(default = 1)

(minimum = 0)

(maximum = 200)

=0 off (default)

=1 on

This only means showing the dots, not doing the actual snapping

=0 off

=1 on (default)

How far apart (in pixels) are the snap to grid hotspots.

(default = 20)

(minimum = 2)

(maximum = 200)


Appendix C

Section

[Edit] ( continued)

[Run commands]

[Fieldbus]


GridColor

Show00

Desc00

Cmnd00

Levl00

Key

AlarmPriority

Setting

Color of the snap to grid dots.

=5570569 invert the panel color

(default)

=66 black

=16711778

white

This setting affects the run command identified by the two digits at the end. This controls how the command is run.

=0 no command defined (default)

=1 iconic

=2 normal

=3 maximized

This setting affects the run command identified by the two digits at the end. It defines the description of the command that will be displayed in the Run menu.

This setting affects the run command identified by the two digits at the end. This is the

DOS-style command itself.

This setting affects the run command identified by the two digits at the end. This is the security level required to run the command.

(default = 10)

Alarm priority for Fieldbus objects.

(default = 0)



Appendix C

[Pots]

[tagname of a pot]

[Recipe]

Section

[S5-AS511]

[Sixnet]


Key

SnapDelay

SnapDelay tagname of a recipe.alarmpriority

Diagnostics

IOMAPAlarmPriority

ProjectAlarmPriority

Setting

When a remoted Pot’s value is changed from a control panel,

LookoutDirect allows this amount of time (measured in seconds) to go by and if the remote value does not change to coincide with the newly selected value, the remoted Pot snaps back to the old value.

(default = 10)

(maximum = 65)

Same value as described above, except you can manipulate this on a

Pot by Pot basis.

(default = [Pots]SnapDelay setting)

Alarm priority used by a Recipe object.

(default = 8)

Turns on diagnostic recording functions in S5-AS511 driver.

When activated, this option logs diagnostic information to the s5as511.dai

file in the

LookoutDirect directory.

=0 diagnostics are off (default)

=1 diagnostics are on

Priority of the "Unable to load

Sixnet IOMAP library: iobase32.dll" alarm in Sixnet.

(default = 5)

Priority of the "No Sixnet configuration currently loaded" alarm in Sixnet.

(default = 5)


Appendix C

[Tiway]

[Graphics]

[DataPath]


Section

[LocalTable]

[tagname of a table]

[tagname of a Tiway]

Delay

Key

EchoCursor

Delay

EchoCursor

UpdateOutputs

UpdateOutputs

Directory

Default tagname of a spreadsheet

Setting

Periodically post a DDE table with this frequency (measured in ms).

(default = 500)

=0 no echoes (default)

=1 only echo a cursor value if the cell the cursor is pointing to does not have a connection to it

Same value as described above, except you can manipulate this on a table-by-table basis.

(default = [LocalTable]Delay setting)

Same value as described above, except you can manipulate this on a table-by-table basis.

(default = [LocalTable]EchoCursor setting)

=0 never update writes (purely event driven) (default)

=1 update all writes every

100 polls

Same value as described above, except you can manipulate this on an object-by-object basis.

(default = [Tiway]UpdateOutputs setting)

Full path to the LookoutDirect graphics directory

Full path to the LookoutDirect data directory

Full path name for an individual spreadsheet



Appendix C

Section

[Registration]

[Defaults]


Key

Company

Key

SerialNumber

Organization

NIInternalCode

Name

HardwareKey

Login

Setting

Serial number of your

LookoutDirect software

Key code issued by National

Instruments

These two entries are for the same piece of information, the organization for which the key was issued.

This is how many days

LookoutDirect has been running. It is only updated in versions of

LookoutDirect where this is important, like the integrator package.

Name for which the key was issued

Hardware key information

Default login name


Index

ABS function,

1-21 accounts assigning security levels (note),

6-4 definition,

6-1 forgetting your password (note),

6-3 modifying,

6-4 acknowledging alarms,

9-11 to

9-13

ACOS function,

1-29 action verification,

6-20

Alarm object class creating alarm objects,

9-2 to ??

alarms,

9-1 to

9-13 acknowledging,

9-11 to

9-13 alarm subsystem,

9-4 to

9-13 areas,

9-4 circular reference alarms,

9-3 database-generated alarms,

9-1 to ??

DDE,

5-5 to

5-6 defining alarm conditions,

9-1 to ??

deselecting,

9-11 display options,

9-7 to ??

filters,

9-8 priorities,

9-6 selecting,

9-11

Alarms window,

9-6 to

9-7 color scheme (table),

9-7 illustration of,

9-6 viewing alarms,

9-6 aliases optional use of (note),

11-5 purpose and use,

11-4 to

11-5

AND function,

1-18

Animator object class displaying dynamic graphics (table),

2-6 to

2-7 arithmetic operators,

1-15


I-1

ASIN function,

1-29

ATAN function,

1-29

ATAN2 function,

1-30

AVG function,

1-24 bitmap (.BMP) graphics compared with Windows metafiles,

2-18 to

2-19 displaying,

2-4 to

2-6

.BMP files. See bitmap (.BMP) graphics

C

CBL compiler,

B-1 circular reference alarms,

9-3

Citadel Historical Database Logger,

7-5 to

7-9 accessing data with ODBC driver,

8-1 to

8-17 data transforms,

8-6 to

8-7

SQL examples,

8-7 to

8-8 traces table,

8-5 using Microsoft Access,

8-13 using Microsoft Excel,

8-13 using Microsoft Query,

8-8 to

8-13 using Microsoft Visual Basic,

8-17 creating historical database,

7-7 to

7-8 data location,

7-5 to

7-6 information overload,

7-9 logging criteria,

7-9 client, DDE,

5-3 to

5-4 colors alarm status (table),

9-7 using in graphics,

2-3 to

2-4 comma-separated value (.CSV) files for Spreadsheet Logger,

7-3 communications service. See serial communications.

comparison operators,

1-15 to

1-18 control panels report generation,

7-11 to

7-13


Index

viewing security,

6-10 controllable objects networking considerations,

A-3 to

A-4 security considerations,

6-9 to

6-10 viewing security,

6-10 to

6-11 conventions, manual, vii to ??

copying object databases,

11-15

COS function,

1-30

.CSV (comma-separated values) files,

7-3

CTS timeout setting,

3-5 custom graphics

See also graphics creating,

2-14 to

2-17 step-by-step example,

2-14 to

2-17 displaying static graphics,

2-4 to

2-6 exporting to Lookout, ?? to

2-16 exporting to LookoutDirect,

2-16 to ??

testing in Lookout, ?? to

2-17 testing in LookoutDirect,

2-16 to ??

data logging


7-5 to

7-9 report generation,

7-11 to

7-13

Spreadsheet Logger,

7-1 to


8-6 to

8-7 dates date/time functions (table),

1-31

DDE (dynamic data exchange),

5-1 to

5-6 alarms,

5-5 to

5-6 client,

5-3 to

5-4 linking Lookout to other applications,

?? to

5-5 linking LookoutDirect to other applications,

5-2 to ??

networking considerations,

A-12 to

A-14 adding trusted DDE share,

A-13 to

A-14 running NETDDE.EXE automatically,

A-12 to

A-13 overview,

5-1 to

5-2

Developer’s Manual I-2

peer-to-peer,

5-4 to

5-5 server,

5-2 to

5-3

DialGauge object class displaying dynamic graphics (table),

2-6 to

2-7

Dialing prefix settings (table),

3-6

Dial-up serial connection,

3-5 to

3-7 displaying expressions,

1-8 to ??

driver objects purpose and use,

3-1 to

3-2 types of,

3-1 dynamic data exchange. See DDE (dynamic data exchange) dynamic graphics,

2-6 to

2-13

See also graphics displaying logical signals,

2-7 to

2-10 numeric signals,

2-10 to

2-11 text signals,

2-12 to

2-13 tools for displaying (table),

2-6 to

2-7 editing database parameters,

11-1 to

11-8 logical parameters,

11-7 to

11-8 numeric parameters,

11-4 to

11-7 text parameters,

11-8 editing object parameters (example),

11-1 to

11-3

Event Logger,

7-10

See also logging data and events data location,


7-10

EXACT function,

1-26

EXP function,

1-22 exporting object databases,

11-9 to

11-13 copying object databases,

11-15 creating database spreadsheet,

11-11 to

11-13 overview,

11-9 procedure,

11-9 to

11-11

Expression dialog box,

1-12 expression functions,

1-18 to

1-31


date/time functions (table),

1-31 logical functions (table),

1-18 to

1-20 lookup functions (table),

1-20

,

1-21 mathematical functions (table),

1-21 to

1-24 statistical functions (table),

1-24 to

1-25 text functions (table),

1-26 to

1-29 trigonometric functions (table),

1-29 to

1-30

Expression object class creating Expression objects,

1-10 to

1-11 expressions,

1-1 to

1-31 as connections,

1-12 as parameters,

1-11 to

1-12 creating,

1-3 to

1-12 displaying on control panels,

1-8 to ??

examples,

1-1 to

1-2 functions,

1-18 to

1-31 illegal conditions,

1-2 to

1-3 result of,

1-1 syntax,

1-14 to

1-18 arithmetic operators,

1-15 comparison operators,

1-15 to

1-18 text operator,

1-15 white space,

1-14 tools for displaying dynamic graphics

(table),

2-6 to

2-7

FACT function,

1-22

FALSE function,

1-19

FIND function,

1-26

FIXED function,

1-26

Gauge object class displaying dynamic graphics (table),

2-6 to

2-7 graphic file types bitmaps vs. metafiles,

2-18 to

2-19 memory considerations,

2-19 graphics,

2-1 to

2-19 animating. See Animator object class


I-3

Index

creating custom graphics,

2-14 to

2-17 dynamic graphics,

2-6 to

2-13 file types,

2-18 to

2-19 screen resolution considerations (note),

2-1 static graphics,

2-2 to

2-6 hardware networking,

A-10

Hardwired serial connections,

3-4 historical database logging. See Citadel

Historical Database Logger

IIII importing object databases copying object databases,

11-15 overview,

11-9 procedure,

11-13 to

11-15 insets displaying in graphics,

2-2 to

2-4

INT function,

1-22

Is equal to (=) operator,

1-16

Is greater than (>) operator,

1-15

Is greater than or equal to (>=) operator,

1-15

Is less than (<) operator,

1-15

Is less than or equal to (<=) operator,

1-15

Is not equal to (<>) operator,

1-16

LCHOOSE function,

1-21

LEFT function,

1-26

LEN function,

1-27

LIF function,

1-19 lines, displaying in graphics,

2-2 to

2-4

LN function,

1-22

LOG function,

1-22

LOG10 function,

1-22 logging data and events,

7-1 to

7-13


7-5 to

7-9

Event Logger,


7-11 to

7-13

Spreadsheet Logger,

7-1 to

7-4 logical data members


Index

editing parameters,

11-7 to

11-8 logical expressions displaying dynamic graphics (table),

2-6 to

2-7 functions (table),

1-18 to

1-20 logical signals, displaying in graphics,

2-7 to

2-10

LOWER function,

1-27 mathematical functions (table),

1-21 to

1-24

MAX function,

1-24 menu bars viewing security,

6-11

Microsoft Access accessing Citadel data,

8-13 compliance with ODBC (note),

8-4

Microsoft Excel, accessing Citadel data,

8-13

Microsoft Query accessing Citadel data,

8-8 to


8-4

Microsoft Visual Basic accessing Citadel data,


8-4

MID function,

1-27

MIN function,

1-24

MOD function,

1-23 modem settings,

3-5 to

3-7 multilink networking,

A-3 to

A-5 compared with table networking,

A-11 linking controllable objects,

A-3 to

A-4 linking non-controllable objects,

A-4 to

A-5

Multistate object class displaying dynamic graphics (table),

2-6 to

2-7

NCHOOSE function,

1-21 networking,

4-1 to

4-7

,

A-1 to

A-14

See also redundancy capabilities,

A-1 to

A-2

DDE considerations,

A-12 to

A-14


adding trusted DDE share,

A-13 to

A-14 running NETDDE.EXE automatically,

A-12 to

A-13 hardware networking,

A-10 methods,

A-2 multilink,

A-3 to

A-5 compared with table networking,

A-11 linking controllable objects,

A-3 to

A-4 linking non-controllable objects,

A-4 to

A-5 overview,

A-2 requirements,

A-1 table networking,

A-6 to

A-9 compared with multilink networking,

A-11 examples,

A-6 to

A-8 routing signals to and from driver objects,

A-8 topography (figure),

A-9 networking considerations controllable objects,

A-3 to

A-4 non-controllable objects,

A-4 to

A-5

NIF function,

1-19

,

1-19

NOT function,

1-19

NOW function,

1-31 numeric data members editing parameters,

11-4 to

11-7 numeric expressions, for displaying dynamic graphics (table),

2-6 to

2-7 numeric signals, displaying in graphics,

O

2-10 to

2-11 object databases copying,

11-15 creating database-generated alarms,

9-1 to ??

editing parameters,

11-1 to

11-8 exporting,

11-9 to

11-11 importing,

11-13 to

11-15


object parameters editing,

11-1 to

11-8 example,

11-1 to

11-3 expressions as parameters,

1-11 to

1-12 logical parameters,

11-7 to

11-8 numeric parameters,

11-4 to

11-7 text parameters,

11-8 objects connecting expressions as connections,

1-12 networking considerations controllable objects,

A-3 to

A-4 non-controllable objects,

A-4 to

A-5

ODBC definition,

8-1

ODBC driver accessing Citadel data,

8-1 to


8-6 to

8-7

ODBC-compliant applications (note),

8-4

SQL examples,

8-7 to

8-8 traces table,

8-5 with Microsoft Access,

8-13 with Microsoft Excel,

8-13 with Microsoft Query,

8-8 to

8-13 with Microsoft Visual Basic,

8-17

Open Database Connectivity (ODBC). See

ODBC operators arithmetic,

1-15 comparison,

1-15 to

1-18 text,

1-15

OR function,

1-19 passwords forgetting your password (note),

6-3 protecting process files,

6-19 to

6-20 revising accounts,

6-4

Pause between calls (modem) setting,

3-7 peer-to-peer links, DDE,

5-4 to

5-5


I-5

Index

PI function,

1-23

Pipe object class displaying dynamic graphics (table),

2-6 to

2-7 plates displaying in graphics,

2-2 to

2-4

Poll Rate,

3-2

Popup control panels viewing security,

6-11 to

6-12

Pot object class displaying dynamic graphics (table),

2-6 to

2-7 displaying dynamic numeric signals,

2-10 to

2-11 printing alarms,

9-10 to

9-11 prioritizing alarms,

9-6 process files protecting,

6-19 to

6-20

PRODUCT function,

1-23

PROPER function,

1-27

Pushbutton object class action verification,

6-20 displaying dynamic graphics (table),

2-6 to

2-7

Radio (RTS/CTS) serial connection,

3-4 to

3-5

RAND function,

1-23

Receive gap setting,

3-3 to

3-4 rectangles, displaying in graphics,

2-2 to

2-4 redundancy,

10-1 basic standby principles,

10-2 failover scenarios,

10-3 standby configuration,

10-4

REPLACE function,


7-11 to

7-13 control panel reports,

7-11 to

7-13 third party reports,

7-13

REPT function,

1-27

Retries (modem) setting,

3-6

RIGHT function,

1-28


Index

ROUND function,

1-23

RTS delay off time period,

3-5

RTS/CTS handshaking settings,

3-4 to

3-5 screen resolution graphics (note),

2-1

SEARCH function,

1-28 security,

6-1 to

6-20 action verification,

6-20 control security,

6-9 to

6-10 overview,

6-1 process file security,

6-19 to


6-10 to

6-12 control panels,

6-10 controllable objects,

6-10 to

6-11 system settings,

6-11 to

6-12 serial communications,

3-1 to

3-7 defining serial port settings,

3-2 to

3-7 dial-up modem settings,

3-5 to

3-7 driver objects,

3-1 to

3-2

Hardwired connections,

3-4 overview,

3-2

Receive gap setting,

3-3 to

3-4

RTS/CTS handshaking settings,

3-4 to

3-5 selecting serial port,

3-3

Serial port data field,

3-3 server, DDE,

5-2 to

5-3

SIGN function,

1-23

SIN function,

1-30 space, in expressions,

1-14

Spinner object class displaying dynamic graphics (table),

2-6 to

2-7

Spreadsheet Logger,

7-1 to

7-4 concurrent file access,

7-4

.CSV files,

7-3 data location,

7-2 to ??

file and disk errors,


7-4

Spreadsheet object class


SQL exporting object database to spreadsheet file,

11-11 to

11-13

See also ODBC driver definition,

8-1

SQRT function,

1-24 standby basic principles,

10-2 configuration,

10-4 failover scenarios,

10-3 static graphics,

2-2 to

2-6 custom graphics,

2-4 to

2-6 displaying text, plates, insets, rectangles, and lines,

2-2 to

2-4 statistical functions (table),

1-24 to

1-25

STDEV function,

1-25

STDEVP function,

1-25

Structured Query Language. See SQL

SUM function,

1-25

Switch object class action verification,

6-20 displaying dynamic graphics (table),

2-6 to

2-7 logical signals in graphics,

2-7 to

2-10 system options, setting for security,

6-9 to

6-10 table networking,

A-6 to

A-9 compared with multilink networking,

A-11 examples,

A-6 to

A-8 routing signals to and from driver objects,

A-8 topography (figure),

A-9 tabs, in expressions,

1-14

TAN function,

1-30

TCHOOSE function,

1-20

,

1-21 text displaying in graphics,

2-2 to

2-4 text data members editing,

11-8


text expressions, for displaying dynamic graphics (table),

2-6 to

2-7

TEXT function,

1-28 text functions (table),

1-26 to

1-29 text operators,

1-15 text signals, displaying in graphics,

2-12 to

2-13 third party reports,

7-13

TIF function,

1-20 time date/time functions (table),

1-31 title bars viewing security,

6-11

TODAY function,

1-31 traces table, for Citadel data,

8-5

Transparent pixel data fields,

2-5 trigonometric functions (table),

1-29 to

1-30

TRIM function,

1-28

TRUE function,

1-20

TRUNC function,

1-24 trusted DDE share,

A-13 to

A-14

UPPER function,

1-29

VAR function,

1-25

VARP function,


6-10 to

6-12 control panels,

6-10 controllable objects,

6-10 to

6-11 system settings,

6-11 to

6-12

Visual Basic accessing Citadel data,


8-4

Wait for connection (modem) setting,

3-6 to

3-7 white space, in expressions,

1-14

Windows Metafile (.WMF) graphics compared with bitmap files,

2-18 to

2-19 displaying,

2-4 to

2-6

.WMF. See Windows Metafile (.WMF)

X graphics

XOR function,

1-20

Index


I-7 Developer’s Manual

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