Abstract: A media manager provides data flow management and other services for client applications on devices coupled together within a network. Preferably, these devices are coupled together within an IEEE 1394-1995 serial bus network. A device control module is generated for each available device for providing an abstraction for all of the capabilities and requirements of the device including the appropriate control protocol, physical connections and connection capabilities for the device. The media manager also manages the flow and format of data transfers between the devices on the network. Through an interface, a user accesses the media manager and enters functions which are to be completed using the devices coupled together on the network. If the appropriate devices are available, the media manager controls and manages the completion of the requested task.

Abstract: A system and method for effectively performing isochronous data transfers comprises a network device including an input/output (I/O) bus that is coupled to an input/output (I/O) node and an isochronous-capable network interface. The network interface and the I/O node may send requests to an arbiter for control of the I/O bus to perform a data transfer operation. In accordance with the present invention, an arbiter filter is interposed between the arbiter and both the network interface and the I/O node to filter respective requests for control of the I/O bus. The network interface advantageously provides an isochronous request to the arbiter filter to thereby de-assert conflicting requests so that the network interface may effectively perform a time-sensitive isochronous data transfer.

Abstract: A system and method for effectively performing physical direct memory access operations comprises a target device with a direct memory access engine that analyzes headers of transfer packets to determine how to successfully perform the physical direct memory access operations. The direct memory access engine includes a notifier module that analyzes notification enable fields from the headers to determine when to provide notifications regarding the occurrence of physical direct memory access operations to device software of the target device.

Abstract: A method for implementing scheduling mechanisms with selectable resource modes comprises at least one resource characterization set that includes a plurality of resource characterizations that each have resource requirements for executing a requested process. The plurality of resource characterizations may include a most mode, a best mode, and a worst mode. An allocation manager may then select a resource mode, and compare the corresponding resource requirements for the requested process to the currently-available device resources. The allocation manager may then authorize or deny the requested process depending upon whether the currently-available resources are sufficient to adequately service the resource requirements of the requested process.

Abstract: Self-describing information is included within a device and contains information relating to a graphical representation of the device, the controls available on the device and the interface required to access those controls. The self-describing information is preferably embedded within a ROM within the device and is read by other devices coupled to the device for presenting a graphical user interface through which the device can be remotely controlled by a user. The self-describing information can also include an address from which additional information about the device and upgrades are automatically obtained. This address is either an internet address or points to a location within a network of devices. The address can also be modifiable. Alternatively, the self-describing information also includes driving software for enhancing the graphical user interface and controlling the operation of the device through another system.

Abstract: Both small frames and large frames of data are transmitted from a producer device to a consumer device over an IEEE 1394 serial data bus. The small frames of data are preferably transmitted to a small frame buffer associated with a plug at the consumer device. Each transfer of a small frame generates an interrupt at the consumer device when the transfer is complete. For the transfer of large frames of data, the consumer device programs an array of page table entries into the plug control register of the producer device, prior to a transfer of a large frame of data. Each of the page table entries includes a starting address of a memory page at the consumer device to which data can be written. Together, these memory pages specified by the page table entries form a large frame buffer at the consumer device for receiving a large frame of data from the producer device. Preferably, the array of page table entries can be updated by the consumer device, as appropriate, between frame transfers.

Abstract: A media manager provides data flow management and other services for client applications on devices coupled together within a network. Preferably, these devices are coupled together within an IEEE 1394-1995 serial bus network. A device control module is generated for each available device for providing an abstraction for all of the capabilities and requirements of the device including the appropriate control protocol, physical connections and connection capabilities for the device. The media manager also manages the flow and format of data transfers between the devices on the network. Through an interface, a user accesses the media manager and enters functions which are to be completed using the devices coupled together on the network. If the appropriate devices are available, the media manager controls and manages the completion of the requested task.

Abstract: A method and apparatus for synchronizing a bus bridge to a master clock comprising receiving a time stamp packet at an input clock register of the bus bridge, comparing the value of the input clock register to the value of an output clock register of the bus bridge, obtaining an error value of the output clock register from the comparison, and determining whether the error value is below a predetermined threshold are described.

Abstract: A method and system for ordering an interconnect topology to form a ring structure, the topology comprising a number of nodes, are described. In one embodiment, a self identifier for each of the nodes is determined. Further, the self identifier is mapped to a ring identifier for each node. In addition, each node computes the ring identifier of one of its port-connected nodes as its topologically adjacent neighbor identifier.

Abstract: An apparatus for and method of separating protocol header information from content data in an IEEE 1394-1995 serial bus network. A receiving node receives isochronous data packets from a transmitting node via a serial bus. Each packet can include a data portion in addition to protocol header information, although not every packet necessarily includes the data portion. Each incoming packet is loaded into a buffer in the receiver as the packet is being received. The protocol header information is removed and stored in sequence in a first block of memory. This is accomplished by placing an input_more direct memory access (DMA) instruction into a next instruction register and, then, executing the instruction. In addition, the receiver is conditioned for removing the data portion from the buffer by loading an input_last DMA instruction into the next instruction register.

Abstract: An isochronous data pipe provides a bi-directional path for data between an application and a bus structure. The isochronous data pipe includes the ability to send, receive and perform manipulations on any isochronous stream of data, including data on any number of isochronous channels. The isochronous data pipe is a programmable sequencer that operates on the stream of isochronous data as it passes through the isochronous data pipe. The isochronous data pipe is programmed by an application to perform specific operations on the stream of data before the data is either transmitted across the bus structure or sent to the application, thereby pre-processing and manipulating the data before it is delivered to its destination. The operations are performed on both the packet header and the data field of the data packet. The isochronous data pipe can be stopped and started on the occurrence of specific events.

Abstract: A media storage device includes an embedded filter for manipulating universal clock based streams of data as they are written to or read from the media storage device. The media storage device will also manipulate streams of data which are not being written to or read from the media storage device. Preferably the embedded filter within the media storage device is an isochronous data pipe which will receive programmed instructions from an external controller and manipulate streams of data according to the programmed instructions in real time, coordinated with the universal clock. Alternatively, the isochronous data pipe includes fixed firmware for performing the appropriate manipulations. The media storage device is also preferably coupled to an IEEE 1394-1995 serial bus structure.

Abstract: A media manager provides data flow management and other services for client applications on devices coupled together within a network. Preferably, these devices are coupled together within an IEEE 1394-1995 serial bus network. A device control module is generated for each available device for providing an abstraction for all of the capabilities and requirements of the device including the appropriate control protocol, physical connections and connection capabilities for the device. The media manager also manages the flow and format of data transfers between the devices on the network. Through an interface, a user accesses the media manager and enters functions which are to be completed using the devices coupled together on the network. If the appropriate devices are available, the media manager controls and manages the completion of the requested task.

Abstract: An isochronous data pipe provides a bidirectional path for data between an application and a bus structure. The isochronous data pipe includes the ability to send, receive and perform manipulations on any isochronous stream of data, including data on any number of isochronous channels. The isochronous data pipe is a programmable sequencer that operates on the stream of isochronous data as it passes through the isochronous data pipe. The isochronous data pipe is programmed by an application to perform specific operations on the stream of data before the data is either transmitted across the bus structure or sent to the application, thereby pre-processing and manipulating the data before it is delivered to its destination. The operations are performed on both the packet header and the data field of the data packet. The isochronous data pipe can be stopped and started on the occurrence of specific events.

Abstract: An applications programming interface implements and manages isochronous and asynchronous data transfer operations between an application and a bus structure. During an asyncronous transfer the API includes the ability to transfer any amount of data between one or more local data buffers within the application and a range of addresses over the bus structure using one or more asynchronous transactions. An automatic transaction generator may be used to automatically generate the transactions necessary to complete the data transfer. The API also includes the ability to transfer data between the application and another node on the bus structure isochronously over a dedicated channel. During an isochronous data transfer, a buffer management scheme is used to manage a linked list of data buffer descriptors. This linked descriptor list can form a circular list of buffers and include a forward pointer to the next buffer in the list and a backward pointer to the previous buffer in the list for each buffer.

Abstract: An isochronous data pipe provides a bi-directional path for data between an application and a bus structure. The isochronous data pipe includes the ability to send, receive and perform manipulations on any isochronous stream of data, including data on any number of isochronous channels. The isochronous data pipe is a programmable sequencer that operates on the stream of isochronous data as it passes through the isochronous data pipe. The isochronous data pipe is programmed by an application to perform specific operations on the stream of data before the data is either transmitted across the bus structure or sent to the application, thereby pre-processing and manipulating the data before it is delivered to its destination. The operations are performed on both the packet header and the data field of the data packet. The isochronous data pipe can be stopped and started on the occurrence of specific events.

Abstract: A media manager provides data flow management and other services for client applications on devices coupled together within a network. Preferably, these devices are coupled together within an IEEE 1394-1995 serial bus network. A device control module is generated for each available device for providing an abstraction for all of the capabilities and requirements of the device including the appropriate control protocol, physical connections and connection capabilities for the device. The media manager also manages the flow and format of data transfers between the devices on the network. Through an interface, a user accesses the media manager and enters functions which are to be completed using the devices coupled together on the network. If the appropriate devices are available, the media manager controls and manages the completion of the requested task.

Abstract: A system and method for multi-level context switching in an electronic network comprises a control state machine configured to implement a data priority scheme, a return address generator configured to hold and release return addresses for interrupted instruction modules in accordance with the data priority scheme and context information from the electronic network, and a processor configured to process data from the electronic network in accordance with the data priority scheme and the context information. Receive registers stores data received from the electronic network. The control state machine includes a switch address generator and a program counter select. The switch address generator outputs a switch address, which is an address for a first instruction for a selected-context instruction module. The return address generator holds and releases the return addresses, which are addresses of next consecutive instructions, when an instruction module is interrupted for a context switch.

Abstract: An apparatus for dispatching a processing element to a program location based on a channel number of received data includes a channel pointer register having a number of storage locations each with a channel number field, a valid bit field and a corresponding instruction pointer field. When an isochronous channel is allocated for use for reception, the host device programs the channel number and a corresponding instruction pointer value into a storage location. When a storage location is programmed, a valid bit within that storage location is also preferably set. The corresponding instruction pointer value points to a series of instructions which are to be used to process data received on that isochronous channel. When isochronous data is then received, the channel number on which the data is received is compared to the channel numbers within the valid storage locations in the channel pointer register.

Abstract: An applications programming interface implements and manages isochronous and asynchronous data transfer operations between an application and a bus structure. During an asyncronous transfer the API includes the ability to transfer any amount of data between one or more local data buffers within the application and a range of addresses over the bus structure using one or more asynchronous transactions. An automatic transaction generator may be used to automatically generate the transactions necessary to complete the data transfer. The API also includes the ability to transfer data between the application and another node on the bus structure isochronously over a dedicated channel. During an isochronous data transfer, a buffer management scheme is used to manage a linked list of data buffer descriptors. This linked descriptor list can form a circular list of buffers and include a forward pointer to the next buffer in the list and a backward pointer to the previous buffer in the list for each buffer.