Diagnostic system

• US 5,357,519 A
• Filed: 10/03/1991
• Issued: 10/18/1994
• Est. Priority Date: 10/03/1991
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Apple Computer Incorporated (Apple Inc.)
• Inventors: Martin, Stephen R., Mooney, Randall O. Jr.
• Primary Examiner(s): Atkinson, Charles E.
• Assistant Examiner(s): Snyder, Glenn
• Application Number:
  US07/771,127
• Time in Patent Office: 1,111 Days
• Field of Search: 371/15.1, 371/16.1, 371/20.1
• US Class Current: 714/25
• CPC Class Codes: G01R 31/31915 In-circuit Testers
• CPC Class Codes: G06F 11/22 Detection or location of defective computer hardware by testing during standby operation or during idle time, e.g. start-up testing
• CPC Class Codes: G06F 11/221 to test buses, lines or interfaces, e.g. stuck-at or open line faults
• CPC Class Codes: G06F 11/2294 by remote test
• CPC Class Codes: G06F 11/261 by simulating additional hardware, e.g. fault simulation
• CPC Class Codes: G06F 11/2736 using a dedicated service processor for test

Abstract

A diagnostic apparatus for testing devices such as computer systems, and computer system components such as disk drives or printers. The device comprises a main unit, the main unit having a central processing unit for executing instructions, issuing commands, and receiving data from a first device. The apparatus also has a first peripheral unit coupled to the main unit, the first peripheral unit having ports for interfacing with the first device, the first peripheral unit being interchangeable with a second peripheral unit for interfacing with a second device. The apparatus also comprises a first non-volatile memory unit coupled to the main unit, the first non-volatile memory unit comprising a first set of tests for the first device, the first non-volatile memory unit being interchangeable with a second non-volatile memory unit comprising a second set of tests for a second device. These interchangeable parts are provided so that the user may test various types of hardware. The apparatus further comprises software means for providing termination on a bus and methods for simulating devices on a bus for remote entry into diagnostic programs.

Claims

1. An apparatus for testing computer systems comprising:

a. a base unit, the base unit comprising a central processing unit for executing instructions, issuing commands, and receiving data from a first computer system;

b. a first connecting module which contains at least one connector for coupling to the first computer system, said connector being coupled to an existing connector on the first computer system, said first connecting module being interchangeable with a second module for interfacing with a second computer system, said at least one connector comprising a disk drive connector; and

c. a first nonvolatile memory module coupled to the base unit, the first nonvolatile memory module comprising a first set of tests for the first computer system, the first nonvolatile memory module being interchangeable with a second nonvolatile memory module comprising a second set of tests for a second computer system, said first set of tests including an initialization circuit causing said first computer system to initially attempt to execute an internally-stored set of diagnostic routines, and if said initialization circuit is unsuccessful at causing said first computer system to attempt to execute said internally-stored set of diagnostic routines, then said initialization circuit causing said apparatus to emulate a disk drive through said disk drive connector and causing said first computer system to perform a bootstrap initialization of said first computer system from said apparatus by loading a set of externally-stored diagnostic routines from said first nonvolatile memory module.

2. The apparatus of claim 1 wherein the base unit comprises a keyboard for entering commands and a display for displaying information to a user.

3. The apparatus of claim 1 wherein the base unit comprises a connector which may be coupled to a third computer system which remotely controls the base unit and issues commands through the base unit to the first computer system.