Change Backlight Level Daily

[DAlter01]

I've got a KP that I want to turn the backlight off each night, then in the morning, turn it on again.  During they day I like it having a backlight but at night I want to get rid of the room illumination it provides.  I remember reading in some forum that constantly writing to the EEPROM of a device will eventually kill the device/signficantly shorten it's lifespan.  Is that true?  Is changing the backlight level writing to the EEPROM or is that just a false assumption of mine and not an issue?   Are there other ways to achieve my objective of having a different backlight level in the day vs the night?

[MrBill]

Re-writing the switch setting is a thing that will lead to eventual early failure.  However rewriting the switch twice a day is 730 times per year.  A quick google suggest the life of an EEPROM might be 100,000 cycles.  Lets say smarthome used cheap EEPROMS tho and the life cycle is only 10,000 cycles... that still means around 13.8 years before failure.   That said... any chip that will fail over time, *might* fail early.  

In our bedroom there are 3 buttons on each of 2 keypads that might be on during the night, one always is they other 2 might be.  Anyway I took the buttons off (removing the 4 little tiny screws) and removed the little clear plastic square and painted it with black fingernail polish (just for those 3), the reinstalled the black square of plastic behind the buttons.  The result is a nice soft outline of light around the button.  It's harder to tell those 3 are lit during the day time, but all 3 are things that you don't really need to see if the button is lit.

[DAlter01]

Th

8 minutes ago, MrBill said:

Re-writing the switch setting is a thing that will lead to eventual early failure.  However rewriting the switch twice a day is 730 times per year.  A quick google suggest the life of an EEPROM might be 100,000 cycles.  Lets say smarthome used cheap EEPROMS tho and the life cycle is only 10,000 cycles... that still means around 13.8 years before failure.   That said... any chip that will fail over time, *might* fail early. 

Mr Bill,

That puts my concern into perspective, thank you.  For me it seems having a KP that might fail at 10-15 years isn't a concern that will keep me from writing the EEPROM 2x a day to acheive my goal.  That is still plenty of lifespan.  And, will I own the house for 10+ years?  Plus I have a half dozen spare KP's to cover the various known/unknown device failure risks.  So, in the end, I view this as a neglible risk solution.  

I like your idea of painting the clear under button.  I've done something similar in another location where I used spray on tint to the those clear under buttons.   The issue I had was the lowest light setting (except for off) was still too bright for my needs.  After applying the spray tint a lot less light comes through which allows much finer control of the lighting level on the KP's as the button still allows some light to come through, just less.