Howto hard reset a Frozen TI-89 Graphing Calculator, Fix Program freezes!
I was running a program i found off the internet and it crashed the calculator. Even after removing/replacing the batteries when i press the ”ON” button the calculator software just crashes.
The following procedure will clear all RAM (this fixed my issue).
Press and hold left arrow, right arrow, and 2nd keys.
Press and release ON.
Additional FAQ info from TI-89.org:
Q5.3: How do I reset my calculator after the programs freeze?
A5.3: Push the buttons LEFT-RIGHT-SHIFT-ON at the same time, and this will probably reset your calculator if you’re using DoorsOS. If you’re not using DoorsOS or if this doesn’t work, a manual method of resetting your calculator that always works (except for problems with the Flash ROM that could potentially be caused by programs that write to the Flash ROM such as HW2Patch, MaxMem, and TIBReceiver) is to take out a battery and while putting it back in, hold the (-) and ) buttons. It will then reset and you can adjust the contrast again.
Q5.4: Why does my calculator reset every time I change my batteries?
A5.4: This shouldn’t normally happen because there exists a lithium backup battery in the TI-89 that prevents it from resetting when replacing batteries. When it dies, though, it doesn’t work anymore and must be replaced. This causes the calculator to reset when removing the other batteries. In order to replace it, remove the normal battery cover. You will see above the four AA batteries a little panel that reads “BACK UP BATTERY.” Remove the panel with a screwdriver and replace the lithium backup battery.
That’s how you hard reset a frozen TI-89 Graphing Calculator, and Fix Program freezes!. Let me know if anyone needs any help on this!