摘要:
A Multiprocessor computer system in which each processor has a fault channel which can be accessed by another processor of the system, thereby permitting operation of the former processor to be monitored by the latter. The fault channel effectively provides the latter processor with all the facilities which are provided to a human operator by the control console of a conventional computer. Each processor is arranged to open its fault channel, and issue a request for attention by another processor, whenever a fault is detected by it.
摘要:
A compiler that completes compilation upon identifying unresolvable input during compilation instead of aborting compilation. This can be accomplished by inserting an exception-throwing instruction, and/or handlers in place of the unresolvable input in the compiled code output. If the section of the compiled code containing the inserted exception throwing instruction is later executed, an exception is thrown and/or handled. Compilation of code from a trusted source can be completed without inserting an exception throwing instruction when the code has only suspected but unverifiable problems.
摘要:
Provided is a method, system, and program for storing input groups of uncoded binary data on a storage medium. A plurality of uncoded data blocks in a data stream are received. An encoded data stream is obtained from concatenating successive encoded blocks such that the encoded data stream includes a predetermined bit pattern comprising a plurality of bits. The bit pattern always occurs within a first number of bits and two occurrences of a “1” or “0” occur within a second number of bits. The encoded data blocks are stored on the storage medium.
摘要:
The present invention is an apparatus and method for detecting a codeword from a data stream comprising a series of sequences of samples representing intensities of an analog signal. The data stream may be output from, for example, a holographic storage device. The data stream is encoded using a code which may be represented by a trellis. One embodiment of the present invention uses a block encoded balanced code, one embodiment uses a finite state encoded balanced code and another embodiment uses a finite-state encoded DC free code. Each code defines a set of codewords which meet the constraints of the code. The codewords are detected from a sequence of samples by selecting the codeword having the greatest correlation with the sequence of samples. In a preferred embodiment, the correlation detection is implemented using the Viterbi process to iteratively determine correlations and codewords for each state at each level of the trellis based on the correlations at the preceding level of the trellis.
摘要:
A version control system such as may be used in an information management system for a source code development project. Multiple versions of artifacts are stored in the version control system. Some versions are stored in uncompressed form while others are stored in compressed form. The artifacts selected to be stored in compressed form are selected to facilitate rapid retrieval of files. The compression process is such that the compression may be performed as a background operation.
摘要:
A method for write-precompensating a waveform for magnetically recording a waveform on a magnetic medium is disclosed. A user data stream is encoded into an encoded data stream so that the encoded data stream has no tribits and no consecutive dibits. No delay is applied to a first transition of a dibit of the encoded data stream. An isolated transition of the encoded data stream is delayed by a first predetermined amount of time. The second transition of a dibit of the encoded data stream is delayed by a second predetermined amount of time, such that the second predetermined amount of time is substantially twice the first predetermined amount of time. Preferably, the encoded data stream satisfies a predetermined run length limited (RLL) k− constraint of k=13 and a predetermined twins t-constraint of t=15. In one embodiment, the encoded data stream is encoded by a block code at rate 8:10. In another embodiment, the encoded data stream is encoded by a block code at rate 16:19.
摘要:
A hard disk drive read circuit for d=1 run length limited (RLL) encoded data which processes multiple consecutive data samples in parallel. The circuit of the present invention receives an analog signal from the read head of the hard disk drive. The circuit comprises a plurality of digital detection channels, coupled to the analog signal, each channel outputting an alternate bit of digital data represented by the analog signal. A timing circuit, coupled to the plurality of digital detection channels, generates a plurality of timing signals controlling the plurality of digital detection channels. The timing circuit derives timing information from one of the digital detection channels. The d=1 RLL code is modified so that there are at most nine consecutive 0's in the digital data output by the digital detection channel from which the timing circuit derives the timing information. An encoder generates the encoded digital data to be recorded on the hard disk drive.
摘要:
The techniques and mechanisms described herein are directed to a method for virtually catching an exception. A debugger receives a notification identifying information about an exception that occurred during execution of an application. The debugger then selectively chooses a location on a call stack where execution of the application resumes after the stack is unwound up to the selected location. The location being between a statement on the stack causing the exception and a handler on the stack. The handler being identified during a search phase for exception processing. The mechanism being operative for both handled exceptions and unhandled exceptions.
摘要:
The present invention relates to a system and methodology to facilitate software development activities via the concept of “Shelving” which provides an improved alternative to conventional branching technologies in certain scenarios. In one aspect, a software development system is provided. The system includes a shelving component that captures a current state of an intermediate software design. A version control component processes the intermediate design as if the intermediate design were a completed software design.
摘要:
A method for designing a computer program for finding a low-complexity coder for constrained block codes for application to timing recovery or error control in data recording systems. The method includes (1) decomposing an input set of candidate codewords into simple subsets of codewords, (2) providing, for each simple subset of codewords, a respective subset of datawords, and (3) filling in certain coordinates in the datawords by values of certain coordinates in the codewords.