Abstract: An external flexible bay system includes an external flexible bay, a modular battery pack and a modular disk drive. The external flexible bay is adapted to receive either the modular battery pack or the modular disk drive to facilitate use of such devices with a portable PC. The external flexible bay includes a parallel port which enables an external I/O device, such as a printer, to be connected thereto. The external flexible bay contains circuitry to automatically sense whether a printer is connected and to determine whether a modular battery pack or modular disk drive has been inserted therein. In order to ensure proper configuration, the external flexible bay includes a mode switch for selecting between a floppy mode and a printer mode.

Abstract: A computer system including circuitry for accurately and economically controlling the charge voltage and charge current at the terminals of its rechargeable battery. During a battery recharge, sensor circuitry coupled to the battery provides accurate data to a battery microcontroller regarding the charge voltage and charge current present at the battery terminals. A battery microcontroller relays this information to a multipurpose microcontroller. The battery microcontroller also provides the desired charging voltage and current as determined by the battery pack's charging algorithm. The multipurpose microcontroller uses the battery status information to program an addressable potentiometer. In turn, the potentiometer generates an adjustment signal that controls the output voltage of the computer's AC adapter. Preferably, the AC adapter is capable of being operated in a constant-power mode.