▲ 2 r/PLC
i everyone, I'm a student working on an automation project and I'm stuck on a communication issue between my virtual PLC and HMI simulation.
The Setup:
- PLC: CODESYS Control Win V3 x64 (Running in Demo Mode/2 hours).
- HMI: Weintek EasyBuilder Pro (Online Simulation mode).
- Protocol: Modbus TCP/IP (Zero-based Addressing).
- Connection: Localhost/Loopback using my local IP (192.168.43.169).
The Problem: I am getting a "Device No Response" error on the HMI simulation.
What I've tried:
- Verified the PLC is in RUN mode.
- Confirmed the Ethernet interface in CODESYS is linked to the correct Wi-Fi adapter (IP 192.168.43.169).
- Disabled Windows Firewall completely (Domain, Private, and Public).
- Mapped variables to
%IX20.0(Bit0) and%IX20.1(Bit1) within the Modbus TCP Server Device I/O Mapping. - Set HMI addresses to 0x 0 and 0x 1.
Despite the PLC console showing that the application is loaded and the Ethernet component has found the IP, the HMI still fails to handshake. Has anyone encountered Error 39 in IoDrvEthernet or the Invalid session ID error in this context?
Any advice on what to check next would be greatly appreciated!
u/Broad-Equipment-8844 — 13 days ago