HIGH-RELIABILITY COMPUTER DIAGNOSTIC SYSTEM

摘要

PURPOSE: To diagnose a computer by providing system processor boards having CPU controlling the operation of a system processor and MCU operating independently of CPU executing a part of diagnosis. CONSTITUTION: MCU 266 normally monitors MCU of the system processor boards 202-208 and a system memory board 210 by receiving status information. When one MCU detects a problem in the system processor boards or the system memory board, diagnosis MCU decides which diagnosis is suitable, transmits information to MCU of the defective board and starts an operation in accordance with decision by MCU of the defective board. Diagnosis MCU decides whether a series diagnosis bus 218 is defective or not and can execute the conventional diagnosis routine of the other component in a diagnosis processor board 212. CPU 258 is different from CPU of the system processor board and it can execute the diagnosis of a high level. The value of CPU 258 does not prevent the continuity of the control of diagnosis in a low level by diagnosis MCU 266.