Well for me im pretty sure my story is somewhat the same but a bit different.
I had accidently let my calculator drain the battery and die, now that i try to charge it. It wont charge and it kept flashing "Calculator will restart when blah blah is done" then i tried the "2nd" and "del" method and now im stuck with the calculator flashing at me to wait and "Please install operating system now." and "Press [clear] to erase all storage" i tried erasing the storage but once it hits "3E' while erasing the storage, the calculator resets and keeps flashing. I even tried hitting the reset button on the back and it basically did nothing. So now im stuck with a broken calculator. I have tried replacing the battery and it did nothing... ;-;