Showing papers by "Agilent Technologies published in 1992"

Insertion of network data checksums by a network adapter

Abstract: A system implements checksumming of a network packet to be sent over a network. A processor constructs the network packet within a main memory. The network packet is transferred from the main memory to a packet storage memory within a network adapter. During the transfer, the network adapter calculates a checksum for the network packet. The network adapter then inserts the checksum into the network packet within the packet storage memory. The network adapter then sends the network packet to the network. In order to calculate the checksum for the network packet, hardware within the network adapter "snoops" an internal bus within the network adapter as the network packet is transported to the packet storage memory. Also, a checksum header is prepended to the network packet which includes control information for checksumming. This control information includes, for example, an indication whether the network adapter is to calculate a checksum and a specification of what data in the network packet is to be checksummed. The control information may additionally include a location within network packet where the checksum is to be inserted.

Surface preparation for chemical-specific binding

Abstract: A mass biosensor uses an intermediate avidin layer to facilitate binding of a biotinylated antibody to a measurement surface of the biosensor. The avidin layer can be added by the manufacturer of the biosensor, while the biotinylated layer can be added by the user. This two-phase method of chemically modifying the measurement surface significantly reduces the user time required to customize the measurement surface to render it capable of binding selected compounds. An organosilane coupling agent attached to the surface provides sites to which avidin is bound. Avidin acts as a universal receptor of biotinylated compounds with specific binding affinities. Biotinylated antibodies or other biotinylated compounds are added and bind to the immobilized avidin. Surface adsorption is reduced by washing the modified surface with biotin to block potential sites of weak bond formation, electrostatic and hydrophobic interactions.

Network adapter for inserting pad bytes into packet link headers based on destination service access point fields for efficient memory transfer

Abstract: A computing system is connected to a network. The computing system includes a network adapter and a main memory. The network adapter receives from the network a network packet having a plurality of headers. The network adapter inserts at least one pad byte within one of the plurality of headers to cause the plurality of headers in the network packet to be aligned along predetermined multi-byte boundaries. For example, the multi-byte boundaries are four-byte boundaries. After inserting the at least one pad byte, the network adapter forwards the network packet to the main memory.

Optical fiber device fabrication

Abstract: An optical device structure for use where an optical fiber requires to be accurately aligned in an optically coupled relationship with another optical component in a package 100 comprises an optical fiber 16 mounted in a feedthrough tube 9 which is aligned with a laser 6 through an aperture 18 in a wall 4 of the package 100. The alignment is held by a first alignment means 10, in this case a sleeve spool, which is secured to the wall 4 and to the feedthrough tube 9 relatively close to the wall 4, and by a second alignment means 11, in this case a tubular bushing, which is also fixed to the wall 4 and to the feedthrough tube 9 in a region remote from the wall 4. The use of the two alignment means 10, 11 fixed in this manner permits the desired optical coupling to be accurately fine-tuned in fabrication by a novel technique.

Isolation of photogenerated carriers within an originating collecting region

Abstract: A photosensing array and a method of making the same wherein the array includes a semiconductor substrate having collecting regions and recrystallized regions. Each collecting region is operatively associated with a photosensing element. Adjacent collecting regions are separated by a recrystallized region. The recrystallized regions are formed by thermally migrating doping metal into the semiconductor substrate using thermal zone gradient melting. With respect to the collecting regions, the recrystallized regions have a relative conductivity level or a conductivity type such that the recrystallized regions have the property of impeding photogenerated carrier migration from one collecting region to an adjacent collecting region. Preferably, the doping metal is one having a high absorption coefficient to block passage of photons between adjacent collecting regions.

Bi-directional socket stimulus interface for a logic simulator

Abstract: A communications socket (FIG. 4) between a logic simulator (202) and a system (206) for generating input stimuli based on the current state of the logic simulator (202) is provided. Input stimuli to the logic simulator (202) for use in implementing a particular circuit design simulation are calculated by interfacing an input program which models the function of the circuit being designed with the logic simulator (202). The lines in this input program are converted by an adaptive vector generator (206) into communications signals which are understandable by the logic simulator (202) so that the desired simulation may take place. The input program thus enables the adaptive vector generator (206) to behaviorally model complex logical systems that the logic simulator model is only a part of and allows for more accurate and detailed simulation. The adaptive vector generator (206) does this by determining the next input vector state in accordance with the present state of the logic simulator model as received from the communications socket. In other words, based on the state data received from the logic simulator (202), the adaptive vector generation (206) automatically calculates the next stimulus pattern for the logic simulator (202) model and provides this stimuli to the logic simulator (202) through the communications socket. This technique removes the tediousness of the prior art techniques in that the design engineer no longer needs to specify every input step and to anticipate the output state of the circuit.

Method and apparatus for locating a predetermined position in a computer file

Abstract: A method and apparatus for locating a predetermined position in a computer file. A continuous, static ECG waveform is displayed in rows on a CRT screen. A scroll bar permits a user to use a computer mouse to click and drag the scroll box to display different portions of the ECG data. When the cursor is on the scroll box and a button on the mouse is depressed, a data window opens adjacent the scroll box and displays the hours, minutes and seconds of the time of day when the ECG waveform of the portion currently displayed was recorded. The data window moves with the scroll box and continues to display current time of the data displayed. When the mouse button is released, the data window closes and the screen changes to display the ECG waveform from the newly selected time.

Bipolar test probe

Abstract: An AC impedance buffer comprising a series of three bipolar transistors in emitter follower configuration is AC coupled to a probe input. An output bipolar transistor has its emitter connected to the output emitter of the AC buffer and its collector provides the probe output. A DC impedance buffer comprises an op amp having inputs connected to the probe input and output and output connected to the base of the output transistor. Another op amp negatively biases the emitter followers so their collectors can be grounded and adds the DC and low frequencies to the AC buffer.

Small value precision integrated circuit resistors

Abstract: The effective parasitic end resistance of small-value precision integrated circuit resistors is reduced by providing N resistors connected in parallel and causing at least two of the resistors to share a terminal contact. The resulting integrated circuit resistor includes multiple terminal contacts of any number n greater than two. Of the n terminal contacts, N-1 terminal contacts are shared amongst said resistors. The parasitic end resistances are diminished by a factor equal to the number of resistors connected in parallel. By increasing the length of the active area of the N resistors by a factor equal to the number of the resistors, the desired resistance value remains undiminished. As a result, the parasitic end resistances may be made negligible compared to the desired resistance even for small value resistors.

Bi-Sr-Ca-Cu-O compounds and methods

Abstract: Compounds of the formula Bi 1 Sr 2 Ca n-1 Cu n O 2n+3+x wherein n is a positive integer and x is less than 1 are formed by molecular beam epitaxial deposition of a plurality of atomic layers on a substrate in the following composition sequence: ##STR1##

Preparing a dye-containing polymer

Abstract: In a process for producing a dye-containing polymer to be used for spectroscopic sample analysis, monomers are polymerized in the presence of a dye to form a block of bulk polymer. The bulk polymer or slices thereof can be easily measured in a spectrometer in order to determine the spectroscopic properties of the dye containing polymer. The bulk polymer is subsequently ground to particles which can be used to fill a fiber optical sensor. Since the particles have the same optical properties as the bulk polymer, the properties of the particles of dye-containing polymer of the sensor can be accurately determined from the bulk polymer.

Dynamic user panels

Abstract: Disclosed is a system that allows a programmer or user to dynamically create a user panel (706, 708), including selecting the icons (808), for an iconic network program, or part of an iconic network program, within an iconic programming environment. The programmer or user may select a show-on-execute option (714) for the panel which causes the panel to be displayed when any one of the icons within the panel is processed by the iconic programming system (1006, 1016). The panel may also be secured by removing all panel options that would allow any change to the panel or the iconic network program (712).

Swept RF and microwave frequency synthesised source

Abstract: The tuning current to the oscillator is initialised to zero to eliminate hysteresis effects. Then, the pretune current is set to produce the minimum operating frequency of the oscillator. Next, the main phase-lock loop is closed, and a low-frequency synthesiser is swept to in turn sweep the oscillator over a selected frequency span. If the selected frequency span extends over other frequency bands, the oscillator is swept to the maximum frequency of the present band and held at this frequency by a track and hold circuit. The main phase-lock loop is opened, the low-frequency synthesiser is re-initialised, the main phase-lock loop is again closed, and the low-frequency synthesiser is swept again. Each frequency band is crossed in a similar manner until the selected frequency span is swept. A phase-lock loop speed-up and stability enhancement circuit comprising a zener diode connected across a passive lag-lead network is incorporated. Pretune calibration for the swept synthesised source is also provided.

Thin-film of a high-temperature superconductor compound and method

Abstract: A thin-film of a high temperature superconducting compound having the formula M 1-x CuO 2-y , where M is Ca, Sr, or Ba, or combinations thereof, x is 0.05 to 0.3, and x>y. The thin film has a T c (zero resistivity) of about 40 K. Also disclosed is a method of producing the superconducting thin film.