Abstract:
A device for a resonant microwave cavity which includes a tuning plunger assembly to make the resonant frequency less temperature sensitive. The frequency response of a cavity filter, determined by its resonant frequency, primarily depends on the dimensions of the filter cavity. Since cavity dimensions will vary with changes in ambient temperature, some form of compensation is necessary to stabilize the frequency response. The tuning plunger assembly is comprised of a sandwich of materials having substantially different coefficients of expansion. One of the materials, a potting compound with a high coefficient of thermal expansion, acts as an operator to vary the configuration of the plunger assembly in order to maintain the resonant frequency of the cavity substantially fixed.
Abstract:
A multiprocessor computer system which maintains cache coherency includes first and second microprocessors each having an associated cache memory storing lines of data. Each line of data has associated protocol bits that indicate a protocol state consistent with write-through, write-back, or write-once cache coherency policies that are selected via a protocol selection terminal for different system configurations. In one configuration, the output and external address terminals of the first microprocessor are coupled to the external and output address terminals, respectively, of the second microprocessor. This configuration enables each microprocessor to snoop memory cycles to main memory initiated by the other microprocessor so that it can be readily determined if a particular cache has the latest version of data.
Abstract:
A pipeline instruction processor for executing instructions stored in an instruction memory, including a plurality of branch instructions. The instruction processor includes a branch target buffer which contains target instructions and target addresses corresponding to branch instructions. The target instruction data is indexed according to the address of the instruction which precedes the branch instruction. Also included in the branch target buffer is history data indicating whether the branch was taken. The instruction processor also includes two execution units. The present invention employs logic which allows a branch instruction and its target instruction stored in the branch target buffer to be executed concurrently in the two execution units according to the history data stored in the branch target buffer. Since the branch instructions and their target instructions are executed during the same cycle, branch instructions appear to be executed in zero cycles.
Abstract:
A tester for a solid state voltage regulator includes two parallel branches available for interconnection to the two output contacts of the voltage regulator. The two branches both interconnect to the high voltage side of a battery. One of the branches includes a resistor in parallel combination with an indicator bulb. One of the branches includes a normally open switch. For use with automobile alternators having a built-in regulator, the tester can be connected directly to the regulator and test both the regulator and the alternator. When the regulator is independent of the alternator, it can be tested by itself by using actual rotor current available from an alternator used in conjunction with the tester. The on/off condition of the indicator bulb, when the switch and various contact terminals are interconnected, provides an indication of the effective operation of the regulator. A volt meter can be included integrally with the tester to provide output readings of the regulator.