tia-plc-operations

Scope

PLC software engineering — full C# Openness implementation.

When the roadmap routes here, the entire solution is C#. Do not mix with Python wrapper calls. Always load tia-csharp-common first (done by roadmap).

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Reference files

Load ONLY the reference file(s) relevant to the task. Do not load all files at once.

Reference file	Load when the task involves
references/online-status.md	Going online/offline, reading PLC state, configuring connection parameters, OnlineProvider, OnlineState, ConnectionConfiguration
references/compare.md	Comparing PLC software or hardware, CompareResult, CompareResultState, CompareToOnline, UpdateProgram
references/blocks.md	Program blocks, system blocks, PlcSoftware root, know-how/write protection, block groups, ProDiag-FB, DataBlock snapshots, compile individual block/UDT, fingerprints, webserver pages, OB priority, loadable file
references/external-sources.md	PLC external source files, importing/generating blocks from sources, PlcExternalSource, PlcExternalSourceGroup
references/tags-types.md	PLC tag tables, tags, user constants, system constants, UDTs, PLC types, UDT group navigation
references/software-units.md	Software units (PlcUnit), PlcUnitProvider, unit relations, unit access/publish, namespaces, name value type documents
references/safety-unit.md	Fail-safe unit (PlcSafetyUnit), SafetyUnit access, safety relations, publish safety blocks
references/safety-administration.md	Global safety settings, SafetyAdministration, safety signature, safety system version, safety runtime groups, safety validation assistant
references/alarms.md	PLC alarms, alarm classes, alarm text lists, PlcAlarmTextProvider
references/technological-objects.md	Technological Objects (TOs), motion control, axes, encoders, TO mapping, hardware connections
references/watch-force-tables.md	Watch tables, force tables, PlcWatchTable, PlcForceTable, watch entries
references/opc-ua.md	OPC UA server interfaces, OPC UA communication groups, access control, role mapping
references/supervision.md	Supervision settings, supervision provider, supervision export/import

For tasks spanning multiple areas, load all relevant reference files before generating code.

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Stub behaviour

If a task targets a partial reference file, do not invent API calls. State clearly which sections are missing. The only remaining stub is import/export signatures in compile-import-export.md — all other files are complete.

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Execution pattern

1. Access PlcSoftware via device's SoftwareContainer
2. Identify which reference file(s) cover the task — load them
3. Navigate Openness object model per reference file patterns
4. For online work: use OnlineProvider service on the CPU DeviceItem (see online-status.md)
5. For compare: use CompareTo / CompareToOnline on PlcSoftware or Device (see compare.md)
6. For software units: access via PlcUnitProvider service on PlcSoftware (see software-units.md)
7. For safety unit: access via PlcUnitProvider.UnitGroup.SafetyUnits (see safety-unit.md)

Access pattern (always needed)

using Siemens.Engineering.HW.Features;
using Siemens.Engineering.SW;

// From a DeviceItem (CPU)
SoftwareContainer sc = deviceItem.GetService<SoftwareContainer>();
PlcSoftware plcSoftware = sc?.Software as PlcSoftware;