A stand-alone portable alarm update tool includes a memory interface for receiving a computer readable memory; a serial port for interconnection to a security alarm panel, by way of a complementary port; a processor; and processor readable memory in communication with the processor, storing software adapting the processor to upload and download configuration files from a removable memory received by the memory port, to the alarm panel, by way of the serial port. Conveniently, the tool may be packaged in a hand-held casing, and which may also house a battery. In this way, the tool may be readily transported by an installer, without being unnecessary heavy or bulky.