When it comes to troubleshooting, you will very likely visit the System log of REXYGEN.
You have the possibility to adjust the amount of information you will see in the System log. To do so, connect to your target device using REXYGEN Studio and go to menu Target -> Configure System Log.
Depending on the problem you are facing, tick as many checkboxes as necessary to get more insight. If you are debugging Modbus communication, you will use the checkboxes in I/O driver messages section. If you are struggling with one particular function block, you will go to the Function block messages section.
Debugging function blocks
Speaking of function blocks, there is one more precondition for enabling messages from the function block. While in Design mode of REXYGEN Studio, make sure that Logging is checked in the function block Properties dialog.