Abstract: This is a system which is used to perform reconfiguration of storage elements in order to permit removal of one or more of the elements for servicing or other reasons. If a storage element that is to be taken off line contains material that is crucial to the continued operation of the system, that material is copied to appropriate areas in other storage elements. After all crucial material has been copied to alternate locations, the original storage element can be taken off line for servicing or other purposes.

Abstract: Disclosed herein is a mechanism for use in a data processing system for recovering from errors detected when reading data from an array. At least two arrays, each of which may be a distinct portion of a single physical array, contain identical data. When data is written, it is written into both arrays. When data is read, it is read from one of the arrays. If an error is detected on readout, there will be a system retry and the other array will be accessed at the next read request. So long as no errors are detected, each successive read will be from the same array. An error detected on readout will cause the next read operation to access the other array.

Abstract: A test circuit that is particularly suitable for inclusion on an LSI chip when testing a new technology. The circuit will enable accurate determination of the turn-on and turn-off delays of a logic circuit on the chip. Two related feedback loops are provided, one of the loops containing the circuit being tested. The differences in time duration between related portions of the two loops correspond to the turn-on and turn-off delays of the circuit being tested.

Abstract: A system and method for analysis of circuits which include a large number of circuit elements. Blocks of circuitry which define logical circuit functions such as gates and latches are set up as macromodels. Each macromodel need be represented in its full detail only once. Means are provided to recognize latency, or quiescence, of macromodels so that time may be saved in the circuit analysis when a macromodel is latent.

Abstract: A pin designed to be attached to a solid state module for making connection between the module and other parts of a metallurgical system. The end of the pin that is to be brazed to the module has a sloping (e.g., conical or wedge) shaped head so that gas bubbles can readily escape during brazing, thus reducing voids in the braze.

Abstract: A method for determining the paths of current flow in an irregularly shaped conductor. A metal is plated onto a substrate in the desired geometric pattern. The metal is then brought to within about 4 percent of its melting point and a current is put through it. After an amount of time that depends upon the temperature and current utilized, there will have been a mass migration in the metal resulting in a corrugated surface having ridges and valleys that are parallel to the current flow. The ridges and valleys may be observed optically or by scanning electron microscope.

Abstract: A cleaning process for a silicon surface, especially a p-type silicon surface. The surface is exposed to HF/H.sub.2 O fumes, thereby obtaining a hexafluosilicic acid film on the surface. The exposed surface is then treated with a water-based, oxidizing, non-silicon-etchant cleaning agent. There is no intermediate rinse between the latter two steps.

Abstract: A formulation comprising, by weight, 4.7-39.7 percent polymethylmethacrylate (PMMA), 0-9.1 percent plasticizer and 60.3-93.0 percent dielectric glass (along with an appropriate amount of solvent) is ball milled to an appropriate size for spraying. After the formulation is sprayed onto a substrate, it is baked at a temperature of approximately 620.degree. C. for approximately 2 hours. During the baking step, the PMMA decomposes to a methylmethacrylate monomer. The resultant dielectric coating will contain a small amount of residue (less than 1 percent) of the monomer and the plasticizer.

Abstract: A method for measuring trace amounts of water in an atmosphere. A dry inert gas is used as the carrier gas and a dry gas comprising about 20 percent oxygen and about 80 percent inert gas is used as the reagent gas. The ionization source is operated at atmospheric pressure. A small electric field of about 200 volts per centimeter is applied across the ion drift chamber and it is biased to repel negative ions to a quadrupole mass filter. Measurements at an m/e value of 52 are integrated over a period of time. The results of the integration, when compared to a calibration chart, indicate the amount of water that had been present in the atmosphere being measured.

Abstract: An absolute difference generator comprises an adder, an Exclusive-OR, two inverters and a latch. One input number is inverted, then presented to one input of the adder while the other input number is presented to the other input of the adder. The carry out line of the adder sets a latch, the output of which is fed back to the carry in line of the adder. The latch output is also combined with the adder output in an Exclusive-OR to control inversion of the adder output and produce the absolute difference between the input data.

Abstract: Apparatus for monitoring and controlling the sequence analysis of processor operations in electronic digital computers. Each flip-flop in a flip-flop chain is associated with an operational step for setting up a monitoring and check sequence. The sequence is controlled by a flip-flop ring and consists of several steps each of which represents a monitoring or check function. An oscillator signal is fed to all flip-flop stages, together with a further control signal. Switching of flip-flops is effected in such a manner that at any one time only one flip-flop is on, its output signal and a coinciding oscillator signal generating a control signal which is converted in an address generator into an address for fetching a subroutine from a storage to control the monitoring and check function associated with the flip-flop.

Abstract: In a data processing system, a mechanism for enabling control to be transferred between programs, or portions thereof, that reside at different addresses in an instruction store. The initial linkage is established through the use of a Branch And Link instruction. Subsequent linkages are established through the use of Return And Link instructions, each of which causes the mechanism to transfer control to a previous program, or program segment, while simultaneously establishing the linkage for a subsequent return to this program or program segment.

Abstract: Multiplier accumulator device for performing the algebraic sum .SIGMA. .+-. A.sub.i B.sub.i of products of n-bit operands expressed in two's complement form. The accumulator is divided in two n-position halves, and the rightmost position of the accumulator is linked to the leftmost position. The product partial sums are alternately accumulated into the left and right halves in such a manner that partial products of like weight are added together. Each position of the accumulator is an adding cell except the leftmost positions of the right and left parts which are subtractive cells.

Abstract: In a multi-processor system which utilizes store-in-cache techniques, a queueing mechanism for insuring that all units that wish to interrogate a memory line will be permitted to interrogate the line. Backing store access requests for data that is contained in the cache of another processor are queued until they can be serviced. The access requests that pertain to particular data are issued from the queue on a first-in-first-out basis. No group of interrogating units will be able to lock out another unit that wishes to interrogate.

Abstract: A probe including means for indicating when the probe has come into physical contact with a target. The probe has a deformable opaque tip containing a transparent window which is normally covered by a shutter. When the probe contacts a target the probe tip deforms, moving the window away from the shutter. Light will be reflected from the target through the window to indicate that contact has been made.

Abstract: An improved system for adding two numbers together. The numbers may be expressed either in binary form or in binary coded decimal form (wherein each decimal digit is represented by its equivalent four binary bits). By taking advantage of "don't care" decimal input conditions, a minimal implementation of a carry look-ahead adder which can operate upon both types of numbers is obtained.

Abstract: Hardware facilities are described whereby the handling of data represented by variable length fields of bits may be made faster, use less storage and be less prone to errors in programming. The bit fields are handled independently of the natural storage addressing elements and boundaries. Data may be packed into main storage with the highest efficiency, and manipulated with a fast and efficient hardware instruction set.

Abstract: A square shaped beam of charged particles is passed over a registration mark in the surface of a semiconductor wafer. A signal produced by a diode detector that is responsive to backscattered electrons will peak when the beam passes over each of the edges of the registration mark. The signal is differentiated; and the resultant signal is filtered and amplified to provide information regarding the position of the beam with respect to the wafer. If more than one diode detector is used, the signals are added just before or just after the differentiation.

Abstract: In a spectrophotometer, light that has passed through, or been reflected from, a sample is carried by a fiberoptic bundle. The output end of the fiberoptic bundle is bonded to one side of a wedge-shaped linear variable interference filter. The other side of the filter is bonded to an array of photodiodes. Because each photodiode receives light that has passed through a different portion of the filter, each photodiode will respond to light of a different wavelength.