I'm using an FMD88-10 in a very basic application as a 2-axis stepper pulse generator. We have some manual buttons, limit switches, and beam sensors all working together in a physical relay network to provide the PLC with "RUN" and "DIRECTION" inputs for each axis. It's a very simple program, basically just STEPMOVE and STEPSTOP in response to these inputs.
A few times now the system has stopped working and upon connecting to the PLC I am presented with dialog box that says:
"Run-Time Error in Fn #5.
Error: DM32[] index out-of-range".
In the ViewVariable dialog I can see the following message being printed to the virtual LCD display:
"Undef. Interrupt
CF #0005:006E"
Other info:
- Custom function 5 is simply the command "STEPSTOP 1".
- I don't have any interrupts defined.
- I don't use or refer to DM[32] anywhere in my program
- The PLC's firmware is version r76A
Thanks for any advice you can offer.
Edit: Corrected typo in error dialog message