Texas Instruments TITANIUM TI-89 - Manual (Page 69)

Getting Started 69
Batteries Batteries Batteries Batteries
The TI-89 Titanium uses four AAA alkaline batteries and a backup silver oxide battery
(SR44SW or 303). The backup battery is already installed, and the AAA batteries are
provided with your product.
Important OS download information Important OS download information Important OS download information Important OS download information
New batteries should be installed before beginning an OS download.
When in OS download mode, the APD  feature does not function. If you leave your
calculator in download mode for an extended time before you actually start the
download, your batteries may become depleted. You will then need to replace the
depleted batteries with new batteries before downloading.
Accessory port
I/O port USB port
TI-89 Titanium ports (teacher model)