Abstract: A method of synchronizing data transmission between a host computer system and a transmitter across an interface with variable delay or latency. The host computer system marks transition frames between successive transmission intervals and transfers the outgoing frames across the variable interface to the transmitter. The transmitter enqueues outgoing frames into one or more FIFO transmission queue(s) and processes the enqueued frames as appropriate for the communication protocol in use. Marked frames are detected as they reach the head of the appropriate transmit queue. In particular, while bypassing is not active, the transmitter transmits unmarked frames until the end of the current interval, or until there is insufficient time in the interval to transmit another frame or until a marked frame is detected. While bypassing is not active, the transmitter terminates transmission from the transmit queue when a marked frame is detected during each interval.

Abstract: An upright-type fire protection water spray mist nozzle has a base defining an orifice through which fire-retardant fluid can flow, an inlet section having an upstream end and defining a conduit for flow of fire-retardant fluid along a orifice axis and leading to an upstream end of the orifice, with a diffuser element defining an impingement surface that is at least substantially imperforate in an axial direction and positioned for impingement by a stream of fire-retardant fluid flowing from the orifice in a stream direction along the orifice axis, the diffuser element being positioned generally above a horizontal plane through a downstream end of the orifice.

Abstract: A context controller for managing multitasking in a processor and a method of operating the same. In one embodiment, the context controller includes: (1) foreground and background task controllers that allocate processor resources to active contexts corresponding to foreground and background tasks, respectively, and (2) mode switching circuitry, coupled to the foreground and background task controllers, that places the processor in an idle state and a power saving mode when all of the contexts are inactive.

Abstract: A context controller for managing multitasking in a processor and a method of operating the same. In one embodiment, the context controller includes: (1) memory that contains contexts corresponding to background tasks to be executed in the processor, the contexts having status indicators associated therewith and (2) a background task controller that reads the status indicators associated with the contexts and cyclicly activates the contexts based on the status indicators.

Abstract: A context controller for managing multitasking in a processor and a method of operating the same. In one embodiment, the context controller includes: (1) an event recorder that records occurrences of events and (2) an encoder, associated with the event recorder, that, in response to a software instruction, priority encodes bits corresponding to at least some of the events to generate therefrom an event-dependent vector to allow the processor to branch as a function thereof. Vectoring is per-instance of the vector decode software instruction, not per-event or per-context.

Abstract: A pendent-type fire protection sprinkler for forming a superimposed combination of an inner, downwardly-directed spray pattern and an outer, umbrella-shaped spray pattern. The pendent-type sprinkler has a body defining an orifice and outlet for flow of fluid from a source and a pair of frame arms extending from the body. The deflector includes a generally plate-like body member defining reentrant slots, which may include a second type of reentrant slots in addition to a first type of reentrant slots, with slots of the second type positioned symmetrically between adjacent slots of the first type. The length of slots of the second type, measured along the slot centerlines extending inwardly from a peripheral edge of the deflector body member generally toward the central axis of the deflector body, being less than the length of slots of the first type.

Abstract: An upright-type fire protection sprinkler with a body defining an orifice and outlet for flow of fluid, and a deflector positioned coaxial with the outlet for impingement of fluid flow thereupon, has one or a combination of the following features for improved performance. The deflector may have an inner surface with a recessed central area, and a recessed redirecting area about the central area at a predetermined acute angle and axial offset thereto. The deflector has tines with inner surfaces inclined towards the outlet, at least a first set of tines disposed in planes at about 45.degree. to a first plane of sprinkler frame arms, the surfaces of the first set of tines being inclined at an angle relatively more outward from the axis than the angle of inner surfaces of adjacent tines.

Abstract: A fire protection nozzle has a base, an orifice, defined by the base and having a predetermined diameter, through which fire-retardant fluid can flow, a inlet section having an upstream end and defining a conduit for flow of the fire-retardant fluid along a conduit axis and leading to an upstream end of the orifice, a diffuser element positioned coaxially with and downstream of the orifice, and one or more arms extending from the base and supporting the diffuser element in a position, where, when flow of the fire-retardant fluid from the inlet section through the orifice is established, the fire-retardant fluid emerges from the orifice in a stream which impinges on a diffuser surface defined by the diffuser element to be distributed in a spray pattern. The diffuser surface defined by the diffuser element is generally spherical in shape in a region extending from an upstream end closest to the orifice to at least downstream of an equatorial plane of the diffuser element transverse to the conduit axis.

Abstract: A communicator station wirelessly transmits frames to and receives frames from a least one additional communicator in a Group in accordance with a MAC protocol. One of the communicators functions as a hub and the remaining communicators function as remotes. The hub sends control information to the hubs to establish repeating communication cycles, each of which has intervals during which the hub and the remotes transmit and receive frames. The intervals allow the hub and the remotes to anticipate transmitting and receiving frames, thereby allowing the remotes to power off their receivers and transmitters to achieve a considerable savings in power consumption without degrading communications. Other improved features include adjusting the intervals and the durations of transmission opportunities in the communication cycle to obtain the beneficial aspects of TDMA and PRMA for LAN-like communication without also incurring most of the undesirable aspects of such MAC techniques.

Abstract: A bridging apparatus provides the capability of transparently and unambiguously communicating LAN packets between two separate LAN segments which have nodes with duplicate IDs. A communicator connected to each LAN segment includes a controller which aliases the source identification (SID) of remotely originated or sourced LAN packets with an unused ID which is an alias (AID) before sending the LAN packet with the AID as its SID on the local LAN segment. The reverse occurs in response to locally sourced LAN packets containing the AID as the DID. The ID of the remote node which correlates to the AID is substituted as the DID before the LAN packet is transmitted to the remote LAN segment. By aliasing in this manner LAN packets are communicated by use of the AIDs between the nodes having the duplicate IDs on the two LAN segments without changing the LAN protocol. Each communicator preferably includes a transmitter and receiver by which to communicate bridge packets between communicators.

Abstract: A fire protection sprinkler including a frame having an outlet opening for fire extinguishing fluid and spaced apart frame arms extending from the outlet opening to provide a support at a location spaced from the outlet opening, a sealing member covering the opening, a thermally responsive member connected between the sealing member and the support to seal off the opening during normal temperature conditions and to release the sealing member during abnornally high temperature conditions, an adapter member attached to the frame, one or more pins that are supported by the adapter member, and a deflector that is slidably mounted with respect to the adapter member via the pin or pins. Also disclosed is a clip that retains the deflector in the retracted position in a releasable fashion.

Abstract: An adaptive throughput control for controlling the transfer of individual bytes of a message communicated between network controllers of adapters at nodes of a LAN enhances or maximizes the rate of transfer of bytes between the sending and receiving nodes at the time of each byte transmission. The adaptive throughput control is embodied in the logic of the network controllers and provides a minimum time gap between sequential ones of the data bytes transferred. The network adapter uses the motherboard DMA or programmed-I/A of the PC attached at the node for obtaining the data transfers between system memory of the PCs, rather than any local intelligence or on-board packet buffering. The adaptive throughput control incorporates handshaking which incorporates a unique signal in each data byte transferred and the unique signal is detected by the receiving network controller and in response to which a response signal is sent when the receiving network controller means is ready to accept the next data byte.

Abstract: Multiple different operational capabilities, such as data transfer rates or communication protocols, are selectable for use on a single LAN. Enchanced nodes of the LAN have the capability of utilizing either an enhanced capability or a common capability in communicating with other nodes. Those basic nodes which are not of the enhanced variety have the capability of communicating utilizing the common capability. The enhanced nodes dynamically select the operational capability for the most efficient communication with other nodes.

Abstract: A transceiver for a LAN is capable of communicating multiple bits per signal element to increase the data throughput of the LAN. The transceiver includes a transmitter which receives a multiple bit digital input value originating at a node of the LAN at which the transceiver is present. The transmitter converts the multiple bit digital input signal into a pulse-like analog signal which is amplitude and phase modulated. A receiver of a transceiver at a receiving node the transmitted analog signal converts its amplitude and phase into a corresponding multiple bit digital output value. A time-domain filter of the receiver creates a primary signal from the received analog signal. To sample the primary signal at its maximum amplitude point, a derivative of the primary signal waveform is used to establish the zero derivative point at which the primary signal attains its maximum amplitude, and to establish a fixed sampling point for subsequent signals.

Abstract: Additional nodes beyond those permitted by the size of the address field of a standard network operating protocol, may be added to a directed token LAN, and the added nodes may be automatically and dynamically configured or reconfigured into a token passing loop. The added nodes, referred to as enhanced nodes, interoperably combine a standard reconfiguration sequence of a standard network operational protocol with an enhanced reconfiguration sequence of an enhanced protocol in order to send tokens to establish the next active nodes of the network and thereby establish the token passing loop through all of the standard and enhanced nodes.

Abstract: An output clock signal is synchronized with predetermined phase accuracy relative to an internal stable frequency reference clock signal upon the application of a transition of an asynchronous event signal. A plurality of phase shifted versions of the reference clock signal are derived. Upon the occurrence of the asynchronous signal, the states of the phase shifted versions are sampled, and that information is utilized as a code to select one of the phase shifted versions from which the output clock signal is derived. Synchronization occurs rapidly within the metastable settling time of the flip-flops of a register which sample or decode the states of the phase shifted versions, or by logical gating arrangements which avoid the necessity for considering the metastable signal. Synchronization is typically obtainable in less than the period of one reference clock signal.

Abstract: Two different communication protocols are interoperatively combined for use in a local area network (LAN). An enhanced protocol can be selected as an alternative to a common protocol during communication between enhanced nodes of the LAN. Signals communicated between nodes of the LAN in the first and second protocols create the appearance of valid activity in both protocols, and always communicate at least some valid information in one of the protocols and selectively communicate additional valid information in a second protocol. Preferably the signals applied in the second or enhanced protocol include signals which are inserted in such a way that they are transparent to the first protocol. Improved network management capabilities and data transfer rates are available as a result of the information communicated in the second protocol.

Abstract: In a token-based local area network, the token may be selectively redirected out of its normal even rotational sequence among all of the active nodes of the network to pass the token more frequently through a priority group of nodes than through a non-priority group of nodes. The priority group is more likely to have messages to initiate from either a numerical or immediacy standpoint, compared to the non-priority group which is less likely to have messages to initiate. When token redirection is not desired, the token is passed in this normal even rotational sequence. Despite redirection, the token is still passed through all of the active nodes on the network in a periodic manner so as to assure normal network activity. Multiple messages can be initiated from a single node before the token is passed to any other node.

Abstract: A sight flow indicator for visually indicating fluid flow through a conduit including a housing that has an inlet and an outlet and defines a flow passage between the two, the flow passage including a sighting region and a downstream restricted region that has a smaller flow area than said sighting region, a window in the housing providing viewing of the sighting region, and an elongated member that is located in the sighting region that is too long to move from the sighting region into the restricted region and is sufficiently smaller than the sighting region so as to be capable of vibrating about in the sighting region in response to flow of fluid therethrough.

Abstract: An I/O network channel achieves relatively high rates of data communication between a plurality of widely physically dispersed devices interconnected by a LAN-type media. A processor connected to each node of the media controls the data and functions of a receiver and transmitter at each node to establish network level, transport level and session level data communication and control functions.