Apparatus and method for testing the operation of a central processing unit of a data processing system

摘要

Apparatus is disclosed for incorporation in a central processing unit that permits a testing procedure to be executed on the central processing unit in a manner that simulates the normal operation of the central processing unit. The apparatus includes an auxiliary memory unit, in which the test programs are stored, and an auxiliary processor for controlling the central processing unit when the test procedure is initiated and for preparing the central processing unit for execution of the test procedures. Control apparatus of the central processing unit executes the test program retrieved from the auxiliary memory unit. The auxiliary processor regains control of the central processing unit after the test program has been executed, tests the results of the test procedure and returns control to the central processing unit.