What happens when you flash a firmware on a rooted device that was not "released for it"?

[SIR Spends-A-Lot]

I have a Samsung sm-t280 with lollipop 5 1 1 which is the highest released ota. Reason: I need nougat or marshmellow to use the sd card as extended internal storage. So the tab a 10" has an Odin firmware for it to upgrade to marshmellow. What happens when you force a firmware not released for your device when rooted? I assume it would be like putting windows 8 on a computer that says designed for windows XP. As long as the system requirements for storage and processor match should work.

 

[Rukbat]

Re: What happens when you flash a firmware on a rooted device that was not "released for it"?

1. Later versions of firmware for Samsung don't allow using the SD card as internal storage either - that's a Samsung thing, and for once, they did the right thing. Using a card like that will destroy it quickly. (SD cards are rated in number of write cycles. Android apps have to keep track of where they are constantly, so every time an app changes anything, it has to write that change to storage. [If you run another app for a moment, and there's not enough free RAM, Android will kill an app to make space. Then, when you bring that killed app to the foreground again, Android will run the app, telling it "pick up from where you left off". To you, it appears that the app has been running in the background all along.] Something like a game is constantly writing to storage as you play. eMMC storage, the kind in the phone, is designed for that. SD isn't.)

2. The very best thing that will happen is that you'll still be able to get back into download mode, so you can flash 5.1.1 again, but otherwise the tablet will be dead. The worst hing would be that you can't even get into download mode and it wouldn't pay to JTAG an old tablet like that - buying a newer one would be cheaper.