Abstract: A system and method of managing power of a multi-function USB device suspends the device in response to receipt of a request to suspend from a USB host; assigns respective device functions to indefinite, locked or unlocked states; allows the device to resume if there are data or requests for host attention pending at a given function that is in the unlocked state and assigning the given function to the locked state; and otherwise maintains the suspend even if there are data are pending at one or more functions that are in the locked state.

Abstract: A system and method of managing power of a multi-function USB device suspends the device in response to receipt of a request to suspend from a USB host; assigns respective device functions to indefinite, locked or unlocked states; allows the device to resume if there are data or requests for host attention pending at a given function that is in the unlocked state and assigning the given function to the locked state; and otherwise maintains the suspend even if there are data are pending at one or more functions that are in the locked state.

Abstract: There is provided a method for replacing a program stored in portable information terminal including a communication unit for transmitting to and receiving data from an external device, a memory unit for temporarily storing a new program and a utility program operating to carry out the replacement of a prestored program, which are received from the communication unit, and a program storage unit for storing the prestored program and replacing the prestored program with the new program. The method comprises the steps of receiving the new and utility programs via the communication unit from an external, storing the new and utility programs in the memory unit, and replacing the prestored program stored in the program storage unit with the new program, using the utility program. As described above, the program of a portable information terminal is replaced using a communication unit instead of an external card, so that the program can be replaced at low cost.

Abstract: A portable information terminal capable of updating a program using a PC card, and a method for updating a program using the same, are provided. The portable information terminal is capable of updating a pre-stored program using a card in which a new program to be updated and a utility program for performing an updating operation are stored. The terminal includes a card unit for reading or writing the new program and the utility program stored in the card, a program storage unit for replacing the pre-stored program with the new program stored in the card and storing the new program, a memory for temporarily storing the new program and the utility program read by the card unit, and a controller for controlling the execution of the utility program stored in the memory so that the new program stored in the memory can be stored in the program storage unit. Thus, a program is correctly updated without an additional special device.

Abstract: A method for booting a personal digital assistant (PDA) using an external memory card is provided. The method includes the steps of (a) preparing an external memory card in which a program for selecting a start-up command is stored, (b) executing a specific start-up command by booting the PDA, (c) executing a program for selecting other start-up commands by inserting the external memory card of the step (a) into the PDA when the step (b) is completed, and (d) executing jobs according to the start-up command selected in the step (c). The hardware switch function is replaced by software by executing a specific start-up command in advance and executing other start-up commands through the application program stored in the memory card of the personal computer during the booting of the PDA. Accordingly, it is possible to reduce fabrication expenses of the PDA, to minimize the PDA, and to flexibly cope with the change of the PDA system.