With the current available operation modes, it is possible to exclusively read or write a variable, but there is no support for readback of output variables.
In my use case it is possible that setpoints in the plc get changed manually by a local touch panel, the internal logic or by an opc-ua connection to another plc. The changed setpoints should synchronize back to epics to keep consistency.
To not affect the current operation modes, adding a new mode called RW or to add info(asyn:READBACK, "1") to the record definition may be an option. These records are included in the cyclic SumRead but also allow writing them on request.
See the discussion on the EPICS Tech Talk for Reference:
https://epics.anl.gov/tech-talk/2024/msg00522.php
With the current available operation modes, it is possible to exclusively read or write a variable, but there is no support for readback of output variables.
In my use case it is possible that setpoints in the plc get changed manually by a local touch panel, the internal logic or by an opc-ua connection to another plc. The changed setpoints should synchronize back to epics to keep consistency.
To not affect the current operation modes, adding a new mode called
RWor to addinfo(asyn:READBACK, "1")to the record definition may be an option. These records are included in the cyclicSumReadbut also allow writing them on request.See the discussion on the EPICS Tech Talk for Reference:
https://epics.anl.gov/tech-talk/2024/msg00522.php