HELP! Runtime Error #81

2013-11-19
2024-07-10
  • MrkTrussell - 2013-11-19

    Does anyone have any information on "Runtime error #81 (access violation Task = MAIN) ?? I can't find any documentation for this error.

    The task throwing the error is the task that runs my main PLC_PRG. I am working on an ABB AC500 PM590 CPU. The error is produced EVERY time I try to RUN the PLC. Therefore, I cannot RUN the PLC.

    The PLC is giving me the following error in conjunction with the above:
    E2: IEC Task 0. Cycle time of IEC task index x - 4 is greater than watchdog time (x = 31 -> IEC task index > 27)

    I have modified the task configuration multiple times now to no avail.

    Any thoughts? Any help is greatly appreciated.

     
  • MrkTrussell - 2013-11-19

    Well, I was able to get the PLC into RUN mode by disabling the MAIN task (the task causing the error). This was expected, but not acceptable.

    I can't seem to find anything in the code that would create a problem here. This program runs on the last generation of the PLC I'm using. It refuses to run on the latest generation.

    I do have more information stating:

    Instruction at 0x00226DE4 attempted to read data at 0x00000000.

    I think this refers to the access violation, but as I stated previously, this code RUNs on the last generation PLCs.

     
  • MrkTrussell - 2013-11-19

    A little more research has lead me to believe that this access violation at address '0x00000000' indicates a null pointer.
    So, I am most likely using something before it's created. Still, I am puzzled as to why this does not create an error on the old PLC.

     
  • shooter - 2013-11-21

    you have a critical something in the tasktime, on old PLc this has worked, but now the watchdog is a lot stricter.
    check for long loops, or if the program takes too much time while waiting
    any program in a PLC must be complete every watchdog time.
    the watchdog is reset when a program or function block ends.
    this is complete different from a basic or C program.

     
  • MrkTrussell - 2013-11-21

    shooter hat geschrieben:
    you have a critical something in the tasktime, on old PLc this has worked, but now the watchdog is a lot stricter.
    check for long loops, or if the program takes too much time while waiting
    any program in a PLC must be complete every watchdog time.
    the watchdog is reset when a program or function block ends.
    this is complete different from a basic or C program.

    Is there a database of these runtime errors somewhere? A lookup table perhaps with descriptions and common causes / remedies?

     
  • shooter - 2013-11-21

    yes in the helpfile and in the docs.

     

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