HMI Persistent variables - Do they exist?

[Yelper85]

Hi all,

Is it possible to make the HMI (HMIGTO2310/2315) remember the last values for certain variables?

I have two language options on the HMI, English and German which can be toggled. This works fine. The problem is, when the HMI gets rebooted it reverts to the default of English.

Currently in the HMI the variables of interest are set to Retentive, and the 'Target System Settings' in 'Preserve Run-Time Data' is enabled, but this doesn't work. Images below.

Is the only solution to have Persistent Variables in the PLC such that when I change on the HMI they get stored in the PLC and upon boot-up they get read, then any change thereafter changes the HMI language directly as well as writing to the PLC variables?

 

[HattoriHanzo · Accepted solution]

Hi

Yes, it is possible:

Greetings

[Yelper85]

Hi @HattoriHanzo,

Many thanks for getting back to me, much appreciated.

Ok, so I can't set the system variables to retentive directly (as per the information in the file you posted), but I could implement interim variables that get stored locally on the HMI rather than the PLC. This would work even if it's an additional step.

I wonder why certain system variables can't be retentive, especially ones like language which in my mind should always retain the last value because say the HMI is out in the field in the middle of the sea (which mine is) and there's a reboot. Suddenly the HMI reverts to the default language which may lead to much confusion, worry, and anger.

Yes you can set the default system and user language to whatever, but that's severely limiting the dynamic aspect when all you want it to do is remember the last language settings.