Abstract: A data processing system and method are disclosed for simulating a hardware fault occurring on an expansion card coupled to the system utilizing a bus. The hardware fault to simulate is specified. A determination is made of a signal to output utilizing the bus to simulate the hardware fault occurring on the expansion card. The signal is output during operation of the expansion card such that the hardware fault occurring on the expansion card is simulated.

Abstract: A secure communication circuit for use with a data communication interconnect adapter and method of operation thereof. The secure communication circuit includes a first data buffer coupled to a data input terminal, an encoder/decoder coupled to the first data buffer, a second data buffer coupled to the encoder/decoder and a switching device coupled to a data output terminal. The switching device is couplable to either the first or second data buffers. A controller, coupled to the (switching device, selectively connects the switching device to the first or second data buffers. In a related embodiment, the secure communication circuit further includes a first serializer/deserializer (SERDES) coupled to the data input and a second SERDES coupled to the switching device.

Abstract: An improved system and method for extending interface communications for a SCSI. The system and method provides SCSI extenders that are able to extend SCSI communications over relatively long distances between at least two SCSI interfaces while also being fast and efficient in operation and inexpensive in implementation. The present system and method reduces latency, buffering, error recovery code, and other such additional hardware and software. SCSI signals are received from one SCSI interface, and the SCSI signals from the one SCSI interface are parallel loaded into a parallel register. The SCSI signals from the one SCSI interface are serialized into serial data, and the serial data from the parallel register is transmitted over an optical communication system. The transmitted serial data is converted back to the SCSI signals that were originally from the one SCSI interface.

Abstract: An analog SCSI switch comprising initiator device ports, target device ports and a controller utilizing at least one analog multiplexor circuit is connected between a SCSI interface and multiple SCSI devices. The controller monitors the SCSI bus and controls all interfaces and ports. By monitoring the SCSI bus, the controller is constantly informed of the arbitration, selection and re-selection acts of the initiator device or target devices. An analog multiplexor circuit selectively connects the initiator device and target device directly, allowing direct communication between the initiator device and a particular target device for duration of the connection. Logic for the controller, contained in the switch onboard memory, utilizes a secondary logical unit number of a target device to map a target device port. Utilizing the analog multiplexor circuit, the switch connects the initiator device port to a selected, mapped target device port.

Abstract: Disclosed are a subsystem and a method for diagnosing a fiber optic network, the fiber optic network comprising a fiber having an optic stream adhering to a defined protocol of the fiber optic network, and comprising a target for receiving and responding to the optic stream. The diagnosis comprises receiving the fiber optic stream and converting the fiber optic stream to an electrical input stream with a FOSA (fiber optic subassembly), and recognizing, from the electrical input stream, a selected event (e.g., frame or command) related to the optic stream defined protocol. Then, in response to the recognition of the selected event, recognizing a selected pattern of the electrical input stream, e.g., employing mask logic, and injecting, in response to the recognition of the selected pattern, a transmission error into the optic stream, and transmitting the optic stream with the injected transmission error to the target, employing a FOSA.

Abstract: An initiator device, in a data processing system utilizing a Serial Storage Architecture subsystem, directs an I/O process via secondary path if a primary path is unavailable, even if the primary path is shorter. Also, an initiator device may send outbound data frames, on a secondary path, simultaneously with the SCSI command. Additional flexibility is attained by utilizing an adapter and target storage devices that all support Out of Order Transfers ("OOT"). If a target supports OOT, individual data frames that comprise an I/O process may be sent on multiple paths, allowing greater flexibility in routing. Also, an initiator device may send outbound data frames, on an alternate path, simultaneously with the SCSI command.

Abstract: Disclosed are a switching system and method for a Small Computer System Interface (SCSI). The SCSI has a plurality of ports coupled to devices having differing priorities including a highest priority (initiator) and lower priorities (targets). The present invention interconnects a plurality of the highest priority initiator devices to the lower priority target devices. A plurality of analog switches are each coupled to one of the initiator device ports and to the lower priority target device ports, preferably on a singular target bus, for selectively interconnecting the coupled initiator device to the lower priority target device ports. A controller is coupled to the initiator devices and to the plurality of analog switches, and is responsive to requests for connection from the initiator devices for arbitrating amongst the initiator devices to operate the analog switches to interconnect only one of the initiator device ports to the lower priority target device ports.