The 9000A-68000 is one of more than 50 microprocessor-specific Interface Pods for use with the 9000-series or 9100-series mainframe. It functions as the test interface between a suspect circuit board's microprocessor circuitry and the mainframe. Each Interface Pod has a self-contained system with its own microprocessor, RAM, ROM, and I/O memory space. The pod can run board-resident programs such as initialization and diagnostics. The Interface Pod uses the board's clock circuit ensuring that all tests are performed at the board's designed speed. Automatic bus line monitoring eliminates the need for probing and enables detection of both static and dynamic faults. The pod has input protection circuitry against overvoltage and incorrect pod insertion. A self-test socket is provided for quick confidence checks.