OpenPLC Runtime v4 vs v3: What Changed and How to Migrate (2026)
OpenPLC v3 is end-of-life. Compare v4 vs v3 architecture, REST/JWT API, plugins (Modbus, OPC UA, EtherCAT, S7), retain in v4.2 and a migration plan.
OpenPLC v3 + Modbus TCP: Open-Source PLC Architecture
OpenPLC v3 reference architecture with Modbus TCP — runtime internals, IEC 61131-3 languages, hardware targets, and a production deployment pattern for open-source PLCs in 2026.