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/fingerprint-data.md	V21 quick-station fingerprint retrieval, FingerprintDataProvider, online/TLS/password callback handling, and fingerprint comparison limits
references/download-upload.md	Live PLC download and station upload, DownloadProvider, StationUploadProvider, callback configurations, fail-closed target handling
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.

Live-operation safety

Treat every live TIA Portal or hardware action as unavailable until the user has explicitly authorized the exact portal instance, project, CPU, and action. A build, stub, offline project, or simulated test is not live evidence. Never infer permission for a download, force, online write, or snapshot load from a request to inspect, compile, compare, or generate code.

Before an authorized live action, report the resolved target and current online state, preserve whether this client established the connection, and disconnect only a connection this client opened. Keep destructive offline changes inside ExclusiveAccess plus a Transaction where supported; compile and verify before saving. Use the deletion safeguards from tia-csharp-common for every Delete() example in the references.

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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 download/upload: require explicit live authorization, resolve the exact target, and fail closed on unhandled callbacks (see download-upload.md)
6. For compare: use CompareTo / CompareToOnline on PlcSoftware or Device (see compare.md)
7. For software units: access via PlcUnitProvider service on PlcSoftware (see software-units.md)
8. 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;