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IBM Journal of Research and Development

Issue 1 • Date Jan. 1980

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Displaying Results 1 - 14 of 14
  • Design of Large ALUs Using Multiple PLA Macros

    Publication Year: 1980 , Page(s): 2 - 14
    Cited by:  Papers (13)  |  Patents (4)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (823 KB)  

    This paper describes methods of designing large Arithmetic and Logical Units (ALUs) using multiple Programmable Logic Array (PLA) macros in which the outputs are obtained in one cycle corresponding to one pass through any PLA. The design is based on the well-known technique of providing conditional sums and group carries in parallel and selecting the proper sum using gating circuits. The PLA for e... View full abstract»

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  • A Heuristic Test-Pattern Generator for Programmable Logic Arrays

    Publication Year: 1980 , Page(s): 15 - 22
    Cited by:  Papers (26)  |  Patents (1)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (514 KB)  

    This paper describes a heuristic method for generating test patterns for Programmable Logic Arrays (PLAs). Exploiting the regular structure of PLAs, both random and deterministic test-pattern generation techniques are combined to achieve coverage of crosspoint defects. Patterns to select or deselect product terms are generated through direct inspection of an array; test paths to an observable outp... View full abstract»

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  • Design Automation and the Programmable Logic Array Macro

    Publication Year: 1980 , Page(s): 23 - 31
    Cited by:  Papers (4)  |  Patents (1)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (716 KB)  

    The Programmable Logic Array (PLA) macro is a physical structure which simplifies LSI chip design while yielding high density and good performance. In addition, the inherent order and regularity of this structure provide opportunities to speed design through automated logic documentation, design verification by computer simulation, and computer-automated physical design. In this paper a chip desig... View full abstract»

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  • Error Recovery Scheme for the IBM 3850 Mass Storage System

    Publication Year: 1980 , Page(s): 32 - 42
    Cited by:  Papers (7)  |  Patents (12)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (862 KB)  

    The IBM 3850 Mass Storage System (MSS) stores digital data on flexible magnetic tape media; however, it is different in many respects from the conventional multitrack tape machines. In particular, the use of a single-element rotary read-write head imposes new demands in the areas of data encoding and error recovery. This paper presents a comprehensive scheme for error recovery for the 3850 MSS whi... View full abstract»

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  • Synchronous Bounded Delay Coding for Input Restricted Channels

    Publication Year: 1980 , Page(s): 43 - 48
    Cited by:  Papers (8)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (459 KB)  

    Consider the class of input restricted channels whose constraints can be modelled by finite state machines. This paper treats the problem of constructing fixed rate (synchronous) codes for such channels subject to a constraint that the coding delay be bounded by a parameter M. M is the maximum number of information symbols required by the coder in choosing a word during transmission. View full abstract»

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  • Determining Deadlock Exposure for a Class of Store and Forward Communication Networks

    Publication Year: 1980 , Page(s): 49 - 55
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (533 KB)  

    Given a network design, is the network exposed to deadlock for message buffers? This problem is addressed for a class of networks called “routed networks.” A routed network is a store and forward communication network in which all transmissions follow predefined routes through the network. It is shown that a routed network is exposed to deadlock if and only if there exists a complete... View full abstract»

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  • On a Class of One-Step Majority-Logic Decodable Cyclic Codes

    Publication Year: 1980 , Page(s): 56 - 63
    Cited by:  Papers (5)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (590 KB)  

    Majority-logic decoding is attractive for three reasons: (1) It can be simply implemented; (2) the decoding delay is short; and (3) its performance, while suboptimal, is always superior to bounded distance decoding. For these reasons, majority-logic decodable cyclic codes are very suitable for error control in high speed digital data transmission systems. Among the majority-logic decodable codes, ... View full abstract»

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  • A Geometric Modeling System for Automated Mechanical Assembly

    Publication Year: 1980 , Page(s): 64 - 74
    Cited by:  Papers (30)  |  Patents (5)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (706 KB)  

    Very high level languages for describing mechanical assembly require a representation of the geometric and physical properties of 3-D objects including parts, tools, and the assembler itself. This paper describes a geometric modeling system that generates a data base in which objects and assemblies are represented by nodes in a graph structure. The edges of the graph represent relationships among ... View full abstract»

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  • On the Complexity of Permuting Records in Magnetic Bubble Memory Systems

    Publication Year: 1980 , Page(s): 75 - 84
    Cited by:  Papers (3)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (649 KB)  

    In this paper we study the problem of permuting records in various simple models of magnetic bubble memories. Previous studies usually assumed the memory system either had one switch or n independently controlled switches, where n is the number of records to be permuted. In the former case, the time complexity to permute a set of n records is O(n2), while in the latter case, the time co... View full abstract»

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  • Interferometric Wavelength Measurements through Post-Detection Signal Processing

    Publication Year: 1980 , Page(s): 85 - 88
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (358 KB)  

    Modern electronic signal processing techniques make it possible to use a conventional scanning Fabry-Perot interferometer for highly accurate measurement of (tunable) laser wavelengths. An experimental device is described in which the time intervals between resonances of an unknown wavelength are compared with those of a stabilized He-Ne reference laser by the use of highly accurate electronic tim... View full abstract»

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  • Pattern Optimization for UPC Supermarket Scanner

    Publication Year: 1980 , Page(s): 89 - 94
    Cited by:  Patents (1)
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (454 KB)  

    Different scanning patterns χ are analyzed in order to determine the degree of redundancy. To this purpose, we evaluate the number of resolution points Nχ which are generated by a sweeping laser beam, while the merchandise is moved across the scanning window. The goal is to find the pattern which minimizes Nχ for an acceptable detection rate. View full abstract»

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  • Recent Papers by IBM Authors

    Publication Year: 1980 , Page(s): 95 - 100
    Save to Project icon | Click to expandAbstract | PDF file iconPDF (539 KB)  

    Reprints of the papers listed here muy usually he obtained by writing directly to the authors. The authors' IBM divisions are identified us follows: CHQ is Corporate Headquarters; DPD, Data Processing Division; DSD, Data Systems Division; FED, Field Engineering Division; FSD, Federal Systems Division; GPD, General Products Division; GSD, General Systems Division; OPD, Office Products Division; RES... View full abstract»

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  • Recent IBM Patents

    Publication Year: 1980 , Page(s): 101
    Save to Project icon | PDF file iconPDF (110 KB)  
    Freely Available from IEEE
  • Authors

    Publication Year: 1980 , Page(s): 102 - 104
    Save to Project icon | PDF file iconPDF (325 KB)  
    Freely Available from IEEE

Aims & Scope

The IBM Journal of Research and Development is a peer-reviewed technical journal, published bimonthly, which features the work of authors in the science, technology and engineering of information systems.

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Meet Our Editors

Editor-in-Chief
Clifford A. Pickover
IBM T. J. Watson Research Center