m8000 Converting PLC - Will this subroutine ever run?

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For some background information, I am in the process of converting a Mitsubishi FX2N to a Siemens S7-1200. I am viewing the Mitsubishi program with GX Developer Version 8.116W.

There is this subroutine in the Mitsubishi program that appears like it will never run. I think the purpose of this subroutine is to clear the status of the devices in the PLC. I have attached a picture that demonstrates what I am dealing with. Can anyone tell if the subroutine P7 will run at any point? Thanks!SUBROUTINE_P7.thumb.png.89d9c86d618b7243

For those who are not used to the Mitsubishi world or want to brush up on their Mitsubishi knowledge, below is some information regarding the devices and functions used in my example:

M8000 - Always on bit (turns on when PLC is running and turns off when PLC is stopped).

M500 - Just some random memory bit I chose.

FEND - Indicates end of main routine program (everything below this rung is either a subroutine or interrupt routine, so it will only be processed if called from somewhere).

P7 on left side of power rail - This is a label that indicates the beginning of the subroutine called P7.

M8031 and M8032 - Special memory bits that, when set, tells the PLC to clear certain devices.

SRET - Indicates end of subroutine.

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As long as the PLC is in run it will not run. Perhaps it is so those items will be cleared if the PLC is switched from run to stop?



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Why does the customer want to change to S7-1200 ? Buy an FX5 and convert the program

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