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Corrupted application is running in a Quantum Hot Standby

Goals and Symptoms

Detected on Quantum Hot Standby CPU whatever the Unity Pro version.
- The application transfer from Primary CPU to Standby CPU never end
- It’s no more possible to upload application from Primary CPU to Unity Pro
- If the CPU memory is fragmented, Unity Pro request a memory pack (red ‘’mem’’ icon in the status bar). Doing a memory pack from Unity Pro with application corrupted will lead to a PLC stop with a stop code A100.

Facts and Changes

All these 3 Quantum CPU behaviors are linked to application corrupted.
Mainly it’s upload code block that is corrupted in CPU memory, means no risk for application code execution.

Causes and Fixes

1st action do not proceed for a memory pack to prevent CPU stop.
How to detected this kind of corrupted application:
From Unity Pro, do an application transferd from PLC to PC.
In ucmerr.log (C:\ProgramData\Schneider Electric\Unity Pro) you will find the following messages that ended with ‘’Error in Checksum for RTE …’’
     [===================== upload application : Project =====================]
     XThrow                                [Tue Apr 01 06:66:00 2016]
     PID   - 5928
     File  - p:\p-unit\dev\appbuild\memalloc\malallocator.cpp (4085)
     Error - E:A0F400A1 - 00000000
     Data  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -
     Error in Checksum for RTE number 0x866
To work around this situation, you need :
     1 To connect with Unity Pro to the Primary CPU and make sure application in the PC is equal with application in the PLC.
     2 Disconnect from Primary & connect to the Standby PLC and load the application to CPU.
     3 As applications are equal data variables are synchronizing from Primary to Standby CPU.
     4 Power off the Primary CPU and the Standby is taking the lead and become new Primary.
     5 If PCMCIA memory card exist in CPU remove it on the CPU that is power off, remove batteries to clear the memory (off 1 min).
     6 Put back PCMCIA in old Primary and power it on by pressing the ESC button on the CPU display (keep it pressed min 5 sec) and release the button.
     7 The CPU is restarting from empty and will load application and data from the new Primary CPU.
     8 Make the CPU restarted in Standby mode.
You have escape from the corrupted application that was deleted from the CPU.
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