The 9100A is a Digital Tester designed to detect and isolate faulty components within digital circuits - on or off the microprocessor bus, in both synchronous and asynchronous circuitry. The 9100A combines signature analysis, logic level detection, frequency and event counting, pulsing, vector stimulus, and emulative testing in one instrument. An IEEE-488 interface allows the 9100A to control and retrieve information from external equipment such as DMM's, signal generators, and counter/timers. Interface pods directly access the UUT's microprocessor kernel. In addition, a single point probe and two types of Input/Output modules let you test digital circuitry beyond the kernel.