Integrated network configuration
Supported buses and devices are configured alongside the PLC application using CODESYS configurators, libraries and device descriptions.
CODESYS · Industrial connectivity
CODESYS Fieldbus & Communication
Integrated Fieldbus, Industrial Ethernet, OPC UA & IIoT Communication
CODESYS Fieldbus & Communication covers communication from field-level I/O through controller-to-controller exchange to supervisory and cloud interfaces. The architecture should distinguish deterministic or cyclic field communication from information-layer protocols such as OPC UA and MQTT.
EtherCATPROFINETEtherNet/IPModbusCANopen
Industrial EthernetEtherCAT · EtherNet/IP · PROFINET
Classic / library protocolsCANopen · J1939 · Modbus
Information layerOPC UA · MQTT
SelectionRole + target dependent
Product role
Communication from field I/O to OT/IT systems
CODESYS Fieldbus & Communication covers communication from field-level I/O through controller-to-controller exchange to supervisory and cloud interfaces. The architecture should distinguish deterministic or cyclic field communication from information-layer protocols such as OPC UA and MQTT.
Integrated network configurationSupported buses and devices are configured alongside the PLC application using CODESYS configurators, libraries and device descriptions.
Communication across automation levelsThe same platform can handle field I/O, controller-to-controller communication and selected OT/IT data exchange.
Explicit security and protocol rolesCertificates, credentials, trust, segmentation and the exact master/device/client/server role must be engineered for the target system.
Architecture role
Separate the control network from the information layer
Define the interfaces and ownership boundaries first; version, licence and target selection should follow the architecture rather than lead it.
01Controller application
02Fieldbus configurator / stack
03I/O & drives
04OPC UA / MQTT
05SCADA / MES / cloud
Confirm the exact target, product version, device package, protocol role, licence and—where applicable—certified safety scope before release to production.
Engineering scope
Integrated fieldbus and higher-level communication
These capabilities define what the CODESYS component contributes to the architecture and what must still be provided by the controller, host platform, network or machine design.
Communication across automation levels
The same platform can handle field I/O, controller-to-controller communication and selected OT/IT data exchange.
Explicit security and protocol roles
Certificates, credentials, trust, segmentation and the exact master/device/client/server role must be engineered for the target system.
Technical selection
Protocol role, target support and cybersecurity requirements
Use this table as a requirement-capture guide. The final implementation should be checked against current CODESYS product documentation, Store data, target documentation and—where relevant—certificates and safety manuals.
| Industrial Ethernet | EtherCAT, EtherNet/IP and PROFINET are key integrated Industrial Ethernet systems supported by CODESYS. |
|---|---|
| Classic and library-based protocols | CANopen, J1939, Modbus TCP/RTU and other protocols are available according to the target and product package. PROFIBUS should be checked against current service/lifecycle status. |
| OPC UA | Server, client and PubSub capabilities are available in the CODESYS ecosystem, depending on the selected runtime and licence. |
| MQTT / IIoT | MQTT and other higher-level protocols are used for data exchange with edge, MES, cloud or other information systems; they are not substitutes for hard real-time field I/O. |
| Protocol roles | A supported protocol name is not enough: scanner/controller, adapter/device, master/slave, client/server and PubSub roles must be verified for the exact target. |
| Cybersecurity | Network zones, certificates, credentials, secure update ownership and remote-access rules should be defined before commissioning. |
Project workflow
Network engineering and commissioning workflow
Move from architecture qualification to engineering, commissioning and lifecycle evidence in a controlled sequence.
Define every communication role
Identify each master, scanner, controller, device, client and server in the architecture.
Confirm the supported scope
Check protocol stacks, configurators, device descriptions and licences against the chosen target.
Engineer timing and security
Set topology, cycle times, synchronisation, certificates, credentials and segmentation together.
Commission with diagnostics
Verify data mapping, error handling, reconnection behaviour, event logging and documentation.
Platform context
Communication layer selection by timing and data purpose
Select field networks by timing and device roles; select OPC UA/MQTT by information-consumer needs. Do not treat them as interchangeable layers.
Current page
CODESYS Fieldbus & Communication
CODESYS Fieldbus & Communication covers communication from field-level I/O through controller-to-controller exchange to supervisory and cloud interfaces. The architecture should distinguish deterministic or cyclic field communication from information-layer protocols such as OPC UA and MQTT.
View role in the platform →Control executionCODESYS Runtime
CODESYS Runtime is the execution layer that turns a compatible target into a programmable controller. The application is created in the Development System, compiled for the selected target, and executed by CODESYS Control—either already integrated by an OEM or installed as a ready-to-use Control SL SoftPLC on a supported platform.
View role in the platform →EngineeringCODESYS Development System
CODESYS Development System is the core engineering environment for creating industrial control applications. It combines IEC 61131-3 programming, device and I/O configuration, libraries, compilation, debugging and online commissioning in one project. The application is engineered here and executed later by a compatible CODESYS runtime.
View role in the platform →Documentation & requirement capture
Official CODESYS documentation and project inputs
Use the official product page for current product information, then provide the project-specific details below so the architecture can be reviewed against the actual machine or system.
Official CODESYS Fieldbus & Communication informationOpen CODESYS ↗Complete CODESYS platform architecturePlatform overview →
Application scopeMachine/process functions, operating modes, cycle-time expectations and whether the project is new design, retrofit or migration.
Target & software baselineController/IPC, CPU architecture, operating system, CODESYS runtime, device package, compiler profile and existing project version.
I/O & communicationLocal/remote I/O, fieldbuses, Industrial Ethernet, OPC UA, MQTT, controller-to-controller links and required protocol roles.
HMI & user accessDisplay hardware, browser clients, independent HMI requirements, alarms, trends, recipes, user roles and remote-service policy.
Motion & functional safetyAxis count, drives, kinematics, CNC/robotics requirements, safe I/O, safe communication and required PL/SIL where relevant.
Deployment & lifecycleController quantity, sites, licensing, backups, certificates, update process, rollback expectations and maintenance ownership.