Abstract: A microcontroller peripheral system is interfaced to the existing keyboard input of an unmodified host computer while supporting normal keyboard operation of the host. The controller is independently powered and responds to keyboard input with the host powered down. The peripheral is interfaceable for controlling or monitoring a wide variety of real world devices, and can power up the host to initialize any desired application program on the host by emulating keyboard input. The controller can establish two-way communication with the host through a serial port by initializing a communication program on the host via emulated keyboard input.

Abstract: An interface for operating a commercially available hand-held infra-red remote or the like through a serial communications port of a host computer has normally open semiconductor analog switches, a ribbon cable connector mateable to the existing connector of the remote's keypad for connecting the switches to the keypad scanning circuit of the remote in parallel with the keypad matrix conductors, and a microcontroller for converting command selecting serial output from the host machine for controlling the analog switches to simulate manual actuation of the keypad and thereby cause the remote to transmit a desired command. The interface package may be installed in the original housing of the remote and concurrent manual and computer operation of the remote remains possible.