Education Technology

Solution 11404: Unexpected Loss of Apps on the TI-89 Family, TI-92 Plus, or Voyage™ 200 Graphing Calculators.

I have lost my applications on my calculator. How did that happen?

When performing certain operations with the TI-89 family, TI-92 Plus, or Voyage™ 200 calculator, Apps can be erased, freeing up archive (or flash) memory. Sometimes this happens unexpectedly. With a better understanding of how applications are stored on the calculator, undesired application deletion could be minimized.

When Apps are being deleted or there is a progress bar either in the status line or in the middle of the screen at start up, the Apps are being moved in memory. If this process is interrupted, for instance by power loss or by dropping the calculator, all of the Apps that have not been successfully moved or re-installed can be lost.

The Apps are stored in the calculator one after the other. This is very much like a stack of boxes. If a box in the middle of the stack needs to be removed, all of the boxes on top of that one must move also. The longer it takes to delete an App, the deeper in the stack of apps it was. Furthermore, the Apps show up on the Var-Link screen in alphabetical order. This most likely is not the order that they are stored in on the calculator.

NOTE: When Apps are being deleted from the calculator, do so with caution. Make sure the batteries are not weak. Do not pull the batteries out while there is a progress bar displayed.

Please see the TI-89 family, TI-92 family and Voyage 200 guidebooks for additional information.