Abstract: A GPIB circuit card including a GPIB controller and GPIB analyzer on the same circuit card. The combined controller and analyzer allows a single connection to the GPIB and only uses a single I/O slot of a host computer. Bus interface circuitry on the card allows both the controller and analyzer to communicate to the host computer using the same bus connector. The GPIB controller preferably operates independently of and concurrently with the GPIB analyzer. Thus, a GPIB circuit card according to the present invention conserves computer resources.

Abstract: A circuit protection device for use with an electrical unit comprises driver circuitry connected to the electrical unit and connecting means electrically connecting the device to the electrical unit to provide a voltage signal indicative of a voltage associated with the electrical unit. A voltage detector is connected to the connecting means and receives the voltage signal, and provides a conditioned voltage signal output representative of the voltage signal. An analog-to-digital converter receives the conditioned voltage signal output and converts the conditioned voltage signal output to a digital value. A digital processing device receives the digital value from the analog-to-digital converter and provides an output signal to the driver circuitry to turn off power to the primary if an error is detected.