Compare Last and Previous Change Values

Here is the idea…

I have a battery operated device that does not have the capability to report battery level, but when operating properly it updates a device variable on an interval of about 60 seconds. So, if there was a way for me to determine that the device was not updated for say 5 minutes it might be a good assumption that the device batteries as dead.

If I create a device properties input based on the device variable that gets updated about 60 seconds, then create an interval schedule, can I create a condition triggered by the interval schedule that checks the delta between the inputs Last Change and Previous Change values that are shown in the Status Report?

This can be done via a forward Reference:
Input:
NewVal …

Cond1 NewVal - OldVal > 10
OldVal NewVal

OldVal will have the previous version of NewVal.