Task overrun when PLC_PRG is deleted from the DDS project

Which products are affected?
EVS93xx-EI (Servo PLC version 6.5 DSMC control board)
EVS93xx-ET (Servo PLC version 6.5 DSMC control board)
EPL-10200-EI (Drive PLC version 6.5)
ECSXA 1X.65 (ECS servo inverter version 6.5)

What happens?
In the cyclic task the drive switches to the task overrun (message keypad: 'ovr PlcPrg'). The current error in code C0168/1 shows a value of 219. All user tasks are stopped; the exceptional response, configured by the user, is activated (response of the target system and of the digital outputs).

When does the problem occur?
The problem occurs if the main program PLC_PRG is deleted in a DDS application. This is generally permissible and used if no program code is to be executed in the cyclic task.

Possible diagnostics?
Display on the keypad: 'ovr PlcPrg'. In the diagnostic code C0168/1 a value of 219 is displayed (timeout in cyclic task).

Short-term measures/recommendations?
The main program PLC_PRG is not to be deleted from the DDS application. Even though the PLC_PRG is not required, it must be included at least in the DDS application with a do-nothing instruction (e. g. a ';' in the programming language 'structured text').

Evaluation:
The function restriction can be avoided by applying the above-mentioned measure. The measure does not represent an additional load for the system.

URL for linking this AKB article: https://www.lenze.com/en-de/go/akb/200407579/1/