Connects to the RS-232 serial port of a PC, laptop, or other host, and provides 8 digital outputs for control, and 2 digital inputs for sensing. The digital outputs are robust enough to directly control the on/off states of other electrical equipment of up to a full ampere in current. The wide range digital inputs not only provide power for dry contacts, but in many cases can be wired directly to contacts which have external voltages already present.