摘要:
A turbine/air vent reeling machine for use in aerial towed target applications and the like disclosed characterized by use of a novel turbine head/air vent design which extracts ram air energy from the wind stream impinging upon a moving aircraft for the purpose of driving and braking the reeling machine for pay-in and pay-out of a towed target. Control of the turbine rotational speed is achieved through plural variable opening vents located aft of the turbine head which are driven through an open and closed orientation by a servo-motor to throttle the air mass flow through the turbine head. Turbine speed is sensed by a tachometer which is coupled to a shaft driven by the turbine. The tachometer output voltage is introduced into a closed loop control circuit including processing electronics which compares the tachometer voltage to a pre-selected set point voltage corresponding to the desired rotational speed of the turbine. The difference between the desired and actual tachometer voltage and its derivative and integral values with respect to time are mixed and amplified to drive the servo-motor to adjust the vent opening in a direction that will cause the turbine to accelerate or decelerate to a desired operational speed. The servo-motor rotation is converted to vent door movement via an actuation mechanism which ensures the vent doors will remain in a closed position in the event that power is removed from the servo-motor.
摘要:
A computer system for executing a binary image conversion system which converts instructions from a instruction set of a first, non native computer system to a second, different native computer system, includes an run-time system which in response to a non-native image of an application program written for a non-native instruction set provides an native instruction or a native instruction routine. The run-time system collects profile data in response to execution of the native instructions to determine execution characteristics of the non-native instruction. Thereafter, the non-native instructions and the profile statistics are fed to a binary translator operating in a background mode and which is responsive to the profile data generated by the run-time system to form a translated native image. The run-time system and the binary translator are under the control of a server process. The non-native image is executed in two different environments with first portion executed as an interpreted image and remaining portions as a translated image. The run-time system includes an interpreter which is capable of handling condition codes corresponding to the non-native architecture. A technique is also provided to jacket calls between the two execution environments and to support object based services. Preferred techniques are also provided to determine interprocedural translation units. Further, intermixed translation/optimization techniques are discussed.
摘要:
A method and apparatus for selectively filling a cache memory with a variable number of data words in response to the size and type of data transfer requested by the processor associated with the cache. According to the present invention a cache fill of either 16 or 64 bytes are provided. If there is a cache miss and an 8 byte word data transfer as requested, the larger fill is provided, similarly, if the 8 byte word data transfer is not requested, the shorter block of data is provided, resulting in enhanced performance over a fixed length cache fill.
摘要:
Executing programs coded in an instruction set of a first computer on a computer of a second, different architecture. An operating system maintains an association between each one of a set of concurrent threads and a set of computer resources of the thread's context. Without modifying a pre-existing operating system of the computer, an entry exception is establishing to be raised on each entry to the operating system at a specified entry point or on a specified condition. The entry exception has an associated entry handler programmed to save a context of an interrupted thread and modify the thread context before delivering the modified context to the operating system. A resumption exception is established to be raised on each resumption from the operating system complementary to one of the specified entries. The resumption exception has an associated exit handler programmed to restore the context saved by a corresponding execution of the entry handler. The entry exception, exit exception, entry handler, and exit handler are cooperatively designed to maintain an association between a one of the threads and an extended context of the thread through a context change induced by the operating system, the extended context including resources of the computer associated with the thread beyond those resources whose association with the thread is maintained by the operating system.
摘要:
A microprocessor chip and methods for execution by the microprocessor chip. Instruction pipeline circuitry has first and second correct modes for processing at least some instructions. A plurality of flags each correspond to a class of instruction occurring in the instruction pipeline circuitry. Pipeline control circuitry cooperates with the instruction pipeline circuitry, as part of the basic execution cycle of the computer, to maintain the value of the flags to record failures of an attempt to execute in the first mode two mode instructions of the corresponding respective instruction classes, to be triggered by a timer expiry to switch the value of the flags, thereby to switch the instruction pipeline circuitry from one of the processing modes to the other for the corresponding instruction class. The mode switch persists for instructions consecutively executed on behalf of a program that was in execution immediately before the timer expiry, beyond any exception handlers invoked consequent to the timer expiry. As each classified instruction comes up for execution in the instruction pipeline circuitry, the instruction pipeline circuitry executes the instruction in a mode determined, at least in part, by the value of the corresponding flag.
摘要:
A method and computer for executing the method. A CPU is programmed to execute first and second processes, the first process programmed to generate a second representation in a computer memory of information of the second process stored in the memory in a first representation. A main memory divided into pages for management by a virtual memory manager that uses a table stored in the memory. DMA (direct memory access) monitoring circuitry and/or software is designed to monitor DMA memory write transactions to a main memory of a computer by a DMA device of the computer; to detect when the first representation is overwritten by a DMA memory write transaction initiated by the second process, without the second process informing the first process of the DMA memory write transaction, the detecting guaranteed to occur no later than the next access of the second representation following the DMA memory write transaction; to record an indication of a location in the main memory written by the DMA memory write transaction, the DMA monitoring circuitry designed to operate without being informed of the DMA memory write transaction by a CPU of the computer before initiation of the DMA memory write transaction, and to provide the indication to the CPU on request; and to report to the first process that the first representation is overwritten by a DMA memory write transaction. The DMA monitoring circuitry includes a plurality of registers outside the address space of the main memory, each register including an address tag and a vector of memory cells, and control circuitry designed to establish an association between a one of the plurality of registers with a region of the memory when a modification to the region is detected by setting the address tag of the one register to an approximation of the address of the region, and to set the values of the memory cells of the vector to record a fine indication of the address of a memory location modified, the control circuitry being operable without continuing supervisory control of a CPU of the computer. Circuitry is designed to record indications of modification to pages of the main memory into the registers. Read circuitry is designed to respond to a read request from the CPU by providing an address of a modified memory location. The virtual memory management tables do not provide backing store for the modification indications stored in the registers.
摘要:
A method and computer for executing the method. A source program is translated into an object program, in a manner in which the translated object program has a different execution behavior than the source program. The translated object program is executed under a monitor capable of detecting any deviation from fully-correct interpretation before any side-effect of the different execution behavior is irreversibly committed. When the monitor detects the deviation, or when an interrupt occurs during execution of the object program, a state of the program is established corresponding to a state that would have occurred during an execution of the source program, and from which execution can continue. Execution of the source program continues primarily in a hardware emulator designed to execute instructions of an instruction set non-native to the computer.
摘要:
A computer system for executing a binary image conversion system which converts instructions from a instruction set of a first, non native computer system to a second, different, native computer system, includes an run-time system which in response to a non-native image of an application program written for a non-native instruction set provides an native instruction or a native instruction routine. The run-time system collects profile data in response to execution of the native instructions to determine execution characteristics of the non-native instruction. Thereafter, the non-native instructions and the profile statistics are fed to a binary translator operating in a background mode and which is responsive to the profile data generated by the run-time system to form a translated native image. The run-time system and the binary translator are under the control of a server process. The non-native image is executed in two different enviroments with first portion executed as an interpreted image and remaining portions as a translated image. The run-time system includes an interpreter which is capable of handling condition codes corresponding to the non-native architecute. A technique is also provided to jacket calls between the two execution enviroments and to support object based services. Preferred techniques are also provide to determine interprocedural translation units. Further, intermixed translation/optimization techniques are discussed.
摘要:
The following specification discloses an aerial gunnery target that is adapted to be towed by an aircraft at high speeds for gunnery training and aircraft weapons qualifications. The assembly comprises a multiplicity of strands or cords such as twisted and plyed polypropylene lines. Each of said strands is secured at the forward end on a towing frame having various configurations which include circles, bars, radial extensions, and other configurations, including hexagons and triangles. The towing frame is pulled by means of a conventional towing cable and may have arms that extend outwardly upon deployment by aerodynamic forces, or may be rigidly constructed in the desired shape. The elongated multiplicity of cords extend backwardly from the frame to a terminal point, such as an analogous frame or a confluence point, such as a ring, where they are attached in coupled relationship, or any other terminal means for securing the ends of the elongated cord elements. The elongated cord elements avoid the coupling of vibratory motion from one cord element to another which results in the oscillatory flapping of targets constructed of conventional fabric. The cords are provided in an array such that they do not create aerodynamic lift and fluttering when being towed. They further prevent the erratic flight that is frequently encountered in conventional rigid targets when they are damaged by gun fire. The multiplicity of elongated cord elements provide a visual surface that appears to be continuous at a distance for target purposes. It also provides a target capable of taking substantial hits without being destroyed, due to the loose configuration of the strands or cords.
摘要:
A computer system for executing a binary image conversion system which converts instructions from a instruction set of a first, non native computer system to a second, different, native computer system, includes an run-time system which in response to a non-native image of an application program written for a non-native instruction set provides an native instruction or a native instruction routine. The run-time system collects profile data in response to execution of the native instructions to determine execution characteristics of the non-native instruction. Thereafter, the non-native instructions and the profile statistics are fed to a binary translator operating in a background mode and which is responsive to the profile data generated by the run-time system to form a translated native image. The run-time system and the binary translator are under the control of a server process. The non-native image is executed in two different enviroments with first portion executed as an interpreted image and remaining portions as a translated image. The run-time system includes an interpreter which is capable of handling condition codes corresponding to the non-native architecute. A technique is also provided to jacket calls between the two execution enviroments and to support object based services. Preferred techniques are also provide to determine interprocedural translation units. Further, intermixed translation/optimization techniques are discussed.