Abstract: A DMA control system includes: a plurality of DMA control units that are controlled in a manner that, while one of the plurality of DMA control units use a transmission path, the other DMA control units other than the one of the plurality of DMA control unit are prevented from using the transmission path; and a transfer instruction unit that defines transfer amounts of DMA transfers for the respective DMA control units and gives transfer instructions thereto. The transfer instruction unit, when the transfer instruction unit gives a transfer instruction to a first DMA control unit of the plurality of the DMA control units, defines a transfer amount for the first DMA control unit and gives the transfer instruction thereto in accordance with a state of utilizing a second DMA control units of the plurality of the DMA control units.

Abstract: A determining unit performs a position determination determining whether a nonvolatile memory is mounted in a right position or in a wrong position. When the determining unit determines that the nonvolatile memory is mounted in the wrong position, a protecting unit protects data stored in the nonvolatile memory.

Abstract: A process control system is provided having a plurality of I/O devices in communication using a bus. A primary redundant I/O device and a secondary redundant I/O device are coupled to the bus, where the secondary redundant I/O device is programmed to detect a primary redundant I/O device fault. The secondary redundant I/O device, upon detecting the primary redundant I/O device fault, publishes a primary redundant I/O device fault message on the bus. The controller may deactivate the primary redundant I/O device and activate the secondary redundant I/O device responsive to the primary redundant I/O device fault message.

Abstract: A method and apparatus for dynamic allocation of DMA buffers in the DRAM banks of an I/O adaptor. The method and apparatus determine the functional status of the adaptor, allocate critical, volatile DMA buffers in non-critical DRAM banks if the adaptor is fully functional, and allocate critical, volatile DMA buffers in critical DRAM banks if the adaptor is partially functional.

Abstract: An input/output subsystem is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. An input/output subsystem image is identified by an input/output subsystem image identifier, which is used by various programs to designate the particular input/output subsystem image for which an I/O operation is to be performed. An operating system is provided with access to a plurality of input/output subsystem images of the input/output subsystem. One or more controls are provided to the operating system image to enable the operating system image to access the plurality of input/output subsystem images.

Abstract: An improved descriptor system is provided in which read pointers indicate to a host and a peripheral the next location to read from a queue of descriptors, and write pointers indicate the next location to be written in a queue. The system also allows an incoming descriptor to point to a plurality of data frames for transfer to the host processor, wherein the peripheral need not read a new descriptor each time a frame is to be transferred to the host.

Abstract: A storage unit stores ranges of devices allocated for each sequence program. A device range checking unit sequentially extracts device notations indicating consecutive areas and commands specifying consecutive devices present in a sequence program, expands devices of the corresponding consecutive areas, and checks whether or not devices of consecutive areas are within a range of devices stored in the storage unit. The device range checking unit sequentially extracts device notations indicating consecutive areas and commands specifying consecutive devices present in a sequence program, expands devices of the corresponding consecutive areas, and checks whether or not devices of consecutive areas are within a range of devices stored in the storage unit.

Abstract: A single host adapter hardware I/O control block contains information used to specify a transfer of data from a host system to a first target device and in addition information that specifies whether the data is to be mirrored, and if so, optionally identifies a second target device on which the data is to be mirrored. After transferring the single hardware I/O control block to the host adapter integrated circuit, the host adapter integrated circuit determines whether the hardware I/O control block specifies a mirrored transaction. If a mirrored transaction is specified, the host adapter integrated circuit generates a second hardware I/O control block for the second target device using the information in the first hardware I/O control block. When the execution of both hardware I/O control blocks is complete, the host adapter integrated circuit provides a single completion notification to the host system.

Abstract: A heterogeneous computer system, a heterogeneous input/output system and a data back-up method for the systems. An I/O subsystem A for an open system and an I/O subsystem B for a mainframe are connected by a communication unit. In order to back up data from at least a disk connected to the I/O subsystem B in a MT library system and in order to permit the mainframe to access the data in the I/O subsystem B, the I/O subsystem A includes a table for assigning a vacant memory address in a local subsystem to the memory of the I/O subsystem A for an open system. A request of variable-length record format received from the mainframe is converted into a fixed-length record format for the I/O subsystem B. The disk designated according to the table is accessed, and the data thus obtained is sent to the mainframe and backed up in the back-up system.

Abstract: A single host adapter hardware I/O control block contains information used to specify a transfer of data from a host system to a first target device and in addition information that specifies whether the data is to be mirrored, and if so, optionally identifies a second target device on which the data is to be mirrored. After transferring the single hardware I/O control block to the host adapter integrated circuit, the host adapter integrated circuit determines whether the hardware I/O control block specifies a mirrored transaction. If a mirrored transaction is specified, the host adapter integrated circuit generates a second hardware I/O control block for the second target device using the information in the first hardware I/O control block. When the execution of both hardware I/O control blocks is complete, the host adapter integrated circuit provides a single completion notification to the host system.

Abstract: A single host adapter hardware I/O control block contains information used to specify a transfer of data from a host system to a first target device and in addition information that specifies whether the data is to be mirrored, and if so, optionally identifies a second target device on which the data is to be mirrored. After transferring the single hardware I/O control block to the host adapter integrated circuit, the host adapter integrated circuit determines whether the hardware I/O control block specifies a mirrored transaction. If a mirrored transaction is specified, the host adapter integrated circuit generates a second hardware I/O control block for the second target device using the information in the first hardware I/O control block. When the execution of both hardware I/O control blocks is complete, the host adapter integrated circuit provides a single completion notification to the host system.

Abstract: In an image forming apparatus for forming an image in accordance with control codes stored in a plurality of memory media, when the control codes stored in the plurality of memory media to control the image forming apparatus is rewritten, rewrite execution codes adapted to execute rewrite of the control codes are transferred to predetermined one of the plurality of memory media from an external apparatus, and rewrite of the control codes is performed in accordance with the transferred rewrite execution codes.

Abstract: Embodiments of the invention may provide a method for implementing an adaptive multimode media queue. A mode of operation may be determined for a received media stream based on a sampling rate of the media stream. The mode of operation may be a wideband mode and/or a narrowband mode. Depending on the determined mode, the adaptive multimode media queue may be partitioned into a low band media queue and a high band media queue. A wideband media stream split into a high band and a low band is buffered into the adaptive multimode media queue wherein the high band is stored in the high band media queue, and the low band is stored in the low band media queue. The high band media queue and low band media queue may be a contiguous memory block within the adaptive multimode media queue. The received media stream, which may have different sampled data rates may be buffered within the partitioned adaptive multimode media queue.

Abstract: A method for verifying data in a storage system is disclosed. A host computer transmits area management data to a storage controller. The area management data specifies a range of a storage area in a storage device to be used by an application program having a mechanism for verifying data suitability. Upon receipt of an input/output request transmitted from the host computer, the storage controller performs verification, which is usually performed by the application program, of the data that is to be processed according to the data input/output request and to be input/output to/from the storage area, which is specified in accordance with the received area management data.

Abstract: A method of and apparatus for efficiently and effectively coupling a newly designed peripheral device to a legacy data processing system. The approach utilizes emulation of a SCSI tape device by a SCSI DVD device. Through device emulation, system-wide modifications are minimized.

Abstract: A computer system implements a standard modem without the use of a microcontroller. Instead, a digital signal processor is provided on an expansion card, but with direct links to the computer system itself. The code usually implemented in the microcontroller is instead implemented as a virtual modem controller to be called by the operating system of the computer itself. Further, this virtual modem controller includes a virtualized UART, that appears to the operating system software as a hardware UART, with entry points for calls to replace input/output instructions. In this way, standard device driver code written to execute input/output operations is easily converted to operate with the “virtualized” UART.

Abstract: A physical interface card for connection to a data bus associated with a data network node is provided. The physical interface card is adapted to perform without supervision from other data bus connected devices: byte ordering, byte alignment and byte scattering/gathering in conveying data between a data bus connected central memory block and at least one data channel associated with the physical interface card. The functionality is provided via a special function direct memory address device operating in accordance with byte ordering specifications for: data stored in the shared memory block and data conveyed via the at least one data channel. The byte alignment is enabled by direct byte addressing techniques as well as the use of an orphan counter to keep track of processed bytes. An implementation of the orphan counter as a state machine reduces processing overheads.

Abstract: Firmware has a plurality of interface modules for mutually transferring signals between a CPU (11) and a plurality of mutually different interface units (40, 41), the type of controller (40a, 41a) is identified by an identifying module, and the CPU (11) is operated by using one of the interface modules corresponding to the controller (40a, 41a). Since the assignment of the controllers (40a, 41a) in memory space of the CPU (11) is different in accordance with the types of the interface units (40, 41), the type of the interface unit (40, 41) can be identified by a return value at a time when data is written in a certain region of the memory space, so that the CPU (11) can be operated in accordance with the type of the interface unit (40, 41).

Abstract: A data input/output apparatus capable of decreasing a number of wires between a sequence controller and a control panel and not requiring a change of the number of the wires even if the number of input/output points of data is increased, provided with switches and light emitting diodes, a plurality of wires which can be directly connected to buses for transmission of data between an I/O unit and a CPU, a plurality of electronic switches connected to the buses by wires, outputting signals in accordance with levels of signals from the buses to the light emitting diodes based on input of a selection signal or outputting signals in accordance with levels of signals input from the switches to the buses, and address decoders connected to the buses by the wires and outputting selection signals to the corresponding electronic switches in accordance with a request from the CPU.

Abstract: A method to write information to a designated information storage medium using an allocated data storage device using a specified information recording format, whereby a previously-determined media bit for the designated information storage medium is examined, and a previously-determined device bit for the allocated data storage device is examined, and the write capability of the designated information storage medium using the specified information recording format is determined.