Data processing system with modified planar for boundary scan diagnostics

• US 5,544,309 A
• Filed: 04/22/1993
• Issued: 08/06/1996
• Est. Priority Date: 04/22/1993
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Cazzolla, John J., Chang, Luke L., Nguyen, Kha D.
• Primary Examiner(s): Beausoliel, Jr., Robert W.
• Assistant Examiner(s): TU, CHRISTINE TRINH LE
• Application Number:
  US08/052,002
• Time in Patent Office: 1,202 Days
• Field of Search: 395/575, 395/183.06, 395/183.01, 371/22.3, 371/22.1, 371/22.5
• US Class Current: 714/30
• CPC Class Codes: G01R 31/318536 Scan chain arrangements, e.g. connections, test bus, analog signals
• CPC Class Codes: G06F 11/2289 by configuration test

Abstract

A boundary scan system for a data processing system using serial scan techniques for diagnostics comprises gated circuitry for each adapter card slot for controlling the propagation of controller generated diagnostic signals throughout the data processing system and the components included on the system'"'"'s planar and each adapter card present, adapted to serially scan all present adapter cards and to provide electrical conduit to the next serially connected component in the absence of a card at an adapter slot.

Claims

1. A personal computer test system, incorporated within a personal computer, for use in accordance with a boundary scan test protocol for serially testing a data processing system within the personal computer having one or more card slots or stations for receiving data processing circuit devices, the personal computer test system comprising:

control means for generating serial test data signals in accordance with the boundary scan test protocol to serially scan in the serial test data signals to the card slots and stations for receiving data processing circuit devices and to scan out serial test data signals from the card slots and stations for receiving data processing circuit devices; and

circuit means connected to each respective card slot and station for receiving data processing circuit devices for receiving the serial test data signals from the control means for either scanning in the serial test data signals to the card slot or station having a data processing circuit device or for scanning out the serial test data signal to the next succeeding serially connected card slot or station for receiving a data processing circuit device in the absence of a data processing circuit device at the respective card slot or station for receiving a data processing circuit device, wherein the circuit means includes a conduit circuit, for scanning in the serial test data signals to scan test the respective data processing circuit device at the respective card slot or station for receiving a data processing circuit device and to scan out the serial test data signals from the data processing circuit device at the respective card slot or station for receiving a data processing circuit device, and wherein the circuit means further includes a gate logic circuit, for scanning out the serial test data signals received from the control means in the absence of a data processing circuit device at the respective card slot or station for receiving a data processing circuit device (i) to a next succeeding serially connected card slot or station for receiving a data processing circuit device or (ii) to the control means for serially testing the data processing system in accordance with the boundary scan test protocol in the absence of a next succeeding card slot or station for receiving a data processing circuit device which card slot or station is in receipt of a data processing circuit device.

2. A data processing system having connecting slots and stations for receiving plug-in data processing components, including I/O adapters and peripheral components, and configured for uninterrupted serial boundary scan diagnostic testing of the plug-in data processing components within the data processing system, comprising:

a central processing unit (CPU) for controlling data within the data processing system;

a CPU local bus connected to the central processing unit for transmission of the data controlled by the central processing unit;

a system bus connected to the CPU local bus for providing further means for transmission of the data and for access to the I/O adapters and the peripheral components;

a controller connected to the system bus for generating diagnostic scan signals in accordance with a boundary scan protocol for serially scanning the diagnostic scan signals through the data processing system including the connecting slots and stations for receiving the plug-in data processing components; and

gate control logic means at each of the connecting slots and stations for receiving the diagnostic scan signals from the controller and for scanning in the diagnostic scan signals to the plug-in data processing components at the connecting slots and stations which are in receipt of the plug-in data processing components, and for passing the diagnostic scan signals in serial sequence from the plug-in data processing components to the next serially connected connecting slot or station for receiving plug-in diagnostic components for passing the diagnostic scan signals to the plug-in data processing components connected at said next serially connected connecting slot or station or, in the absence of plug-in data processing components connected at said next serially connected slot or station, for passing the diagnostic scan signals to the next succeeding serially connected connecting slot or station for receiving plug-in data processing components to thereby provide for uninterrupted serial boundary scan diagnostic testing of the plug-in data processing components at each connecting slot and station within the data processing system even in the absence of plug-in data processing components at any respective connecting slot or station.

3. The data processing system as defined in claim 2, configured for uninterrupted serial boundary scan diagnostic testing wherein each gate control logic means comprises a tri-state gate.

4. The data processing system as defined in claim 3, configured for uninterrupted serial boundary scan diagnostic testing wherein the diagnostic scan signal passes through the tri-state gate in the absence of plug-in data processing components at the respective connecting slot or station.

7. The data processing system as defined in claim 3, configured for uninterrupted serial boundary scan diagnostic testing wherein, in the absence of any of the data processing components inserted at any of the respective connecting slots or stations, the respective tri-state gate is enabled and the diagnostic scan signals are scanned in serial sequence in accordance with the boundary scan protocol for serially scanning the diagnostic scan signals through the data processing system, including the slots and stations for receiving the plug-in data processing components.

5. A data processing system having connecting slots and stations for receiving plug-in data processing components, including I/O adapters and peripheral components, and configured for uninterrupted serial boundary scan diagnostic testing of the plug-in data processing components within the data processing system, comprising:

a central processing unit (CPU) for controlling data within the data processing system;

a CPU local bus connected to the central processing unit for transmission of the data controlled by the central processing unit;

a system bus connected to the CPU local bus for providing further means for transmission of the data and for access to the I/O adapters and the peripheral components;

a controller connected to the system bus for generating diagnostic scan signals in accordance with a boundary scan protocol for serially scanning the diagnostic scan signals through the data processing system including the connecting slots and stations for receiving the plug-in data processing components; and

gate control means comprising a tri-state gate at each of the connecting slots and stations for receiving the diagnostic scan signals from the controller and for scanning in the diagnostic scan signals to the plug-in data processing components at the connecting slots and stations which are in receipt of the plug-in data processing components, and for passing the diagnostic scan signals in serial sequence from the plug-in data processing components to the next serially connected connecting slot or station which is in receipt of the plug-in data processing component, or in the absence of plug-in data processing components connected at said next serially connected slot or station, for passing the diagnostic scan signals through the tri-state gate to the next succeeding serially connected connecting slot or station for receiving plug-in data processing components to thereby provide for uninterrupted serial boundary scan diagnostic testing of the plug-in data processing components at each connecting slot and station within the data processing system even in the absence of plug-in data processing components at any respective connecting slot or station.

6. The data processing system as defined in claim 5, configured for uninterrupted serial boundary scan diagnostic testing wherein any tri-state gate is in a high impedance off state and blocks the diagnostic scan signals from by-passing any of the inserted data processing components at the respective connecting slot or station.