kize

Toshiba's telephone cpu's contain both ram and rom IC's. The rom is the startup info- program numbers and tables, system instructions. The ram saves the add on program features you build or change. The battery sel jumper is used for new startup installs and resets. Toshiba ships and stores the cpu batt off- keeps the cpu card safe from esd damage in storage and shipment. After about 3 to 5 years of batt being left without system power on would eventually die. First time system lost power with dead cpu battery- you would have a corupt database when system restarts. I learned along time ago when in doubt- reinitialize. There has been many random system problems due to installers not completing proper startup proceedures. Toshiba had several tech note on this. Hope this answers some questions.