NEMA IA2.3:2005
NEMA IA2.3:2005 Programmable Controllers - Part 3: Programming Languages Describes syntax and semantics of programming languages for programmable controllers.
Table of Contents
FOREWORD1General
1.1Scope
1.2Normativereferences
1.3Definitions
1.4Overviewandgeneralrequirements
1.4.1Softwaremodel
1.4.2Communicationmodel
1.4.3Programmingmodel
1.5Compliance
1.5.1Systemcompliance
1.5.2Programcompliance
2Commonelements
2.1Useofprintedcharacters
2.1.1Characterset
2.1.2Identifiers
2.1.3Keywords
2.1.4Useofwhitespace
2.1.5Comments
2.1.6Pragmas
2.2Externalrepresentationofdata
2.2.1Numericliterals
2.2.2Characterstringliterals
2.2.3Timeliterals
2.3Datatypes
2.3.1Elementarydatatypes
2.3.2Genericdatatypes
2.3.3Deriveddatatypes
2.4Variables
2.4.1Representation
2.4.2Initialization
2.4.3Declaration
2.5Programorganizationunits
2.5.1Functions
2.5.2Functionblocks
2.5.3Programs
2.6SequentialFunctionChart(SFC)elements
2.6.1General
2.6.2Steps
2.6.3Transitions
2.6.4Actions
2.6.5Rulesofevolution
2.6.6CompatibilityofSFCelements
2.6.7SFCCompliancerequirements
2.7Configurationelements
2.7.1Configurations,resources,andaccesspaths
2.7.2Tasks
3Textuallanguages
3.1Commonelements
3.2Instructionlist(IL)
3.2.1Instructions
3.2.2Operators,modifiersandoperands
3.2.3Functionsandfunctionblocks
3.3StructuredText(ST)
3.3.1Expressions
3.3.2Statements
4Graphiclanguages
4.1Commonelements
4.1.1Representationoflinesandblocks
4.1.2Directionofflowinnetworks
4.1.3Evaluationofnetworks
4.1.4Executioncontrolelements
4.2Ladderdiagram(LD)
4.2.1Powerrails
4.2.2Linkelementsandstates
4.2.3Contacts
4.2.4Coils
4.2.5Functionsandfunctionblocks
4.2.6Orderofnetworkevaluation
4.3FunctionBlockDiagram(FBD)
4.3.1General
4.3.2Combinationofelements
4.3.3Orderofnetworkevaluation
ANNEXA(normative)Specificationmethodfortextuallanguages
A.1Syntax
A.1.1Terminalsymbols
A.1.2Non-terminalsymbols
A.1.3Productionrules
A.2Semantics
ANNEXB(normative)Formalspecificationsoflanguageelements
B.0Programmingmodel
B.1Commonelements
B.1.1Letters,digitsandidentifiers
B.1.2Constants
B.1.3Datatypes
B.1.4Variables
B.1.5Programorganizationunits
B.1.6Sequentialfunctionchartelements
B.1.7Configurationelements
B.2LanguageIL(InstructionList)
B.2.1Instructionsandoperands
B.2.2Operators
B.3LanguageST(StructuredText)
B.3.1Expressions
B.3.2Statements
ANNEXC(normative)Delimitersandkeywords
ANNEXD(normative)Implementation-dependentparameters
ANNEXE(normative)Errorconditions
ANNEXF(informative)Examples
F.1FunctionWEIGH
F.2FunctionblockCMD_MONITOR
F.3FunctionblockFWD_REV_MON
F.4FunctionblockSTACK_INT
F.5FunctionblockMIX_2_BRIX
F.6Analogsignalprocessing
F.6.1FunctionblockLAG1
F.6.2FunctionblockDELAY
F.6.3FunctionblockAVERAGE
F.6.4FunctionblockINTEGRAL
F.6.5FunctionblockDERIVATIVE
F.6.6FunctionblockHYSTERESIS
F.6.7FunctionblockLIMITS_ALARM
F.6.8StructureANALOG_LIMITS
F.6.9FunctionblockANALOG_MONITOR
F.6.10FunctionblockPID
F.6.11FunctionblockDIFFEQ
F.6.12FunctionblockRAMP
F.6.13FunctionblockTRANSFER
F.7ProgramGRAVEL
F.8ProgramAGV
F.9Useofenumerateddatatypes
F.10FunctionblockRTC(RealTimeClock)
F.11FunctionblockALRM_INT
ANNEXG(informative)Referencecharacterset
Index