Global variable access by Programms and Modbus Devices (attach device to bus)

2024-07-18T11:27:11.709000Z

Hi everyone. I use Raspberry Pi 4, one core codesys SL.
I have a question about global variable access via programm when I glued the same variable to MODBUS SERIAL/TCP DEVICE holding register.
So, the question: what behavior of this modifying?
When I set "Always update variables (in bus cycle)" and set some task as bus for the Device, then in another task I cant change this varible (can, but immediatly the old value setted again).
But the same things works with MODBUS SLAVE: again "Always update..." and master attached to some task, then I change variable in another task and all works.
I cant set up my variables from retains file at PrepareStart event because of this behavior with MODBUS SERIAL/TCP DEVICE.

Thanks, wbj0t.

Recent posts to Global variable access by Programms and Modbus Devices (attach device to bus)

Global variable access by Programms and Modbus Devices (attach device to bus)