Abstract: A JTAG bus cross point switching device that is commanded by the same bus which it configures. In a preferred embodiment a JTAG chain includes a cross point switching device that is capable of adding, omitting, or rearranging devices on a JTAG bus. The switching device itself is controlled by commands on the JTAG bus which it configures.

Abstract: A JTAG bus cross point switching device that is commanded by the same bus which it configures. In a preferred embodiment a JTAG chain includes a cross point switching device that is capable of adding, omitting, or rearranging devices on a JTAG bus. The switching device itself is controlled by commands on the JTAG bus which it configures.

Abstract: Commanding a JTAG bus cross point switching device by the same bus which it configures. Adding, omitting, or rearranging devices on a JTAG bus with a cross point switching device that is included in a JTAG chain. Controlling the switching device with commands on the JTAG bus which it configures.

Abstract: A method of automatically determining errors and appropriate solutions to those errors in a PCI-based computer system is disclosed. The method is easy to maintain and efficient, because it eliminates the need for inefficient and difficult-to-understand program code containing large numbers of cascaded conditional statements.

Abstract: A method and implementing apparatus is provided which include a plurality of perceptible indicia devices which are mounted on an I/O drawer of a computer system server equipment rack. In the exemplary embodiment, the indicia devices include a light-emitting diode in combination with an alphanumeric display device. Various states of a system initialization process are indicated by different combinations of possible states of the LED and the display device such that the sequencing of a system initialization process can be traced by visual inspection of the status of the perceptible indicia devices.

Abstract: A multitude of devices coupled to a processor are each given a location code, which is then displayed in proximity to each of the devices. Then, when the processor indicates an error within a particular device, the service person can easily find which device has the error by the displayed location code associated with the device.

Abstract: Polling of devices on an inter-IC (I.sup.2 C) is provided. An expansion processor resides on a primary I.sup.2 C bus. The expansion processor is coupled to a plurality of I.sup.2 C sub-buses each of which may host a plurality of I.sup.2 C devices. Data is transferred between the expansion processor and the plurality of I.sup.2 C devices via the corresponding sub-bus according to an I.sup.2 C protocol. Data transfer is in response to a request initiated by a bus master on the primary I.sup.2 C bus. The bus master communicates with a target device residing on one of the sub-buses by addressing the expansion processor. The bus master informs the expansion processor of the target device by sending the expansion processor a number of the sub-bus on which the target device resides, and an address of the target device. A data stream bound for the target device is directed to the expansion processor which then echos it to the target device.