From Onyx (I guess) 10.2 to Onyx 12.2, you need to set up the plotter connection in the Cutserver to „file“ or „folder“ (not shure about the correct name, I’m not in the workshop), what saves PLT-files. Then start summa cutter control, click on the „Barcode Server“-Button, set the folder you have saved the PLT-Files into as the working directory, activate the barcode server and click on the barcode Icon (or start it from the plotter).
If you use Onyx 18, the barcode server is integrated in the Cutserver itself. There is an option to check in the plotter configuration window to activate it (not shure about the name). If correctly configured, you can start barcode reading at the plotter.
The last time I have checked it (with a beta of Onyx 18), barcode was supported only if the plotter was connected to the network, not USB. Could be that it have changed until now. Summa cutter control works with network and USB.
Onyx (around) 10.1 or older does not support OPOS Barcode at all.
Sorry for typing errors, I wrote that on a cell phone.