Showing papers on "Interface (computing) published in 1970"

An analysis of the instruction execution rate in certain computer structures

Abstract: : The purpose of the thesis is to present a series of models of digital computers at the level of the memory processor interface A discussion of computer instructions is presented and the single address format is taken as the prototype instruction The execution rate for instructions of this type is then determined for several computer structures of the single processor and general multiprocessor types The effect on the execution rate of a specialized processing activity, input/output handling, is considered Analytic models relate the instruction execution rate to the memory and processor speeds, their number, and their interconnection Simulation studies serve to verify the results of the analysis A simple automatic design program is proposed which optimally configures computer structures from a set of available components

Programmable computer-peripheral interface

Abstract: An interfacing network for providing asynchronous data transfers directly with a computer memory and external devices. Computer instructions from the computer arithmetic unit are decoded in an executive control unit. Certain instructions ready an input or output channel control unit which thereafter controls data transfers with a selected external device. Each transfer is made directly with the computer memory and does not require interruption of the program being processed in the arithmetic unit. Once the input or output channel control unit assumes control of the transfer, the executive control unit is immediately available to perform other functions independently and concurrently. It may ready the other channel control unit and monitor external device and interface conditions including the readiness of an external device to transmit data. Certain monitored conditions cause the interfacing network to interrupt normal computer operation. Various control signals in the executive control unit are translated to and from control signals in the computer and external devices to permit the utilization of common instructions.

Perspectives on the computer revolution

Abstract: This is a completely revised and updated edition of this text designed to introduce students to the historical, intellectual and social context of computers Although the majority of the chapters in this edition are new, the original criteria for selecting essays has been retained The text retains the historical pieces and adds new material on artifical intelligence, the human-computer interface, the intellectual importance of computing, and the social imapct of computer technology

On-Line Acquisition of Data from Raman and Infrared Spectrometers with a Time-Sharing Computer

Abstract: Considerations leading to the interface and software design of an on-line data acquisition system are presented. The system makes extensive use of conversation mode programing and the nature and extent of the operator-computer program interactions are discussed. The system employs close-loop control of the acquisition process with the possibility of operator intervention at any stage. Control actions and data reduction may be initiated asynchronous to the data acquisition process. An illustration of the use of the system for correcting relative Raman intensities is given.

Digital communication interface

Abstract: The digital communication interface facilitates the transfer of blocks of data between the memories of two computers and provides for maximum data density of information storage when the two computers involved have different word sizes. Once initialized, the interface transfers data via cycle-steal with respect to the two computers'' memories. Either computer may detect the status of the interface at any time during a data transfer and can halt or modify the operation as desired. When a transfer operation has been completed, the interface can signal either or both computers. The interface includes a data register which is divided into two sections. The number of bits in each section corresponds to the number of bits in the memory word of each of the two computers. Thus, if the two computers have different word sizes, the two sections of the data register will have different lengths. The data register is a circular bidirectional shift register which provides a parallel-to-serial-to-parallel data path. The operation of the interface during data-transfers is completely controlled by registers internal to itself which can be loaded by either computer. The condition of the data-handling circuits is indicated at all times by these registers which can also be read by either computer. This allows the interface to be commanded fully by either computer or by both. The control registers are capable of controlling the unit size of contiguous groups of data words transferred between the memories of the two computers such that the unit size may be either the least common multiple of the word size of each of the two computers or the smaller of the two word sizes. In the latter case a word-for-word relationship is maintained, whereas this is not true in the former case. The former case, however, permits high-density packing of the data from the memory of one computer to the memory of the second computer. The control registers are also capable of independently varying the effective length of each section of the data register. This permits data from one section to be introduced into the other at any bit position.

Data terminal-computer serial interface system having automatic baud rate switching

Abstract: Interface circuits for transmitting digital information serially from a computer data terminal through a transmit data line to a computer and also in the reverse direction through a receive data line from the computer to the data terminal provide automatic electronic switching responsive to transmission of information through the transmit data line for disconnecting the pulse output of a high frequency clock from a single interface clock line, and at the same time connecting a lower frequency clock to this clock line. The clocks control transmit and receive registers in the interface to produce one rate of data transmission when no data is being transmitted in the direction from the data terminal to the computer and a lower rate of data transmission when data is being transmitted in such direction. A terminal busy inhibit signal from the data terminal may also be employed to prevent transmission of clock pulses by the clock line when the data terminal is not ready to receive data.

Modular audio-visual control system

Abstract: A modular control system which is adaptable to be controlled either manually or by a tone generator such as a touch-tone telephone or a prerecorded tape, includes a modular selection means which selectively provides one of a plurality of particular audio-visual device control paths from one of a plurality of operational mode control paths which are common to a plurality of audio-visual devices, and a momentary device control path which is particular to one of the devices. The modular selection means includes means for selectively providing a momentary device control path from a plurality of such paths, with a different one of such paths being associated with a different one of the devices. An audio-visual device control interface module is removably connected between the modular selection means and each of the devices to be controlled. The interface module provides a portion of the plurality of audio-visual device control functions, such as three, for the device connected thereto, a different one of such functions being provided for a different one of the audio-visual device control paths. The interface module includes either a latch relay and a pair of momentary relays connected in parallel, or three latch relays connected in parallel depending on the functions desired. A bidirectional motor is connected to the pair of momentary relays of such an interface module to provide momentary rotary control functions, such as focus control for a projector, with one direction being associated with each relay.

Stereoscopic television system

Abstract: A method and apparatus for broadcasting stereoscopic images via a conventional color television system. A pair of monochrome TV cameras are situated to view the same scene from two separated positions. Stereoplex interface circuitry disclosed herein converts outputs from these cameras to luminance and chrominance signals which are supplied to a color television transmitter. A composite color signal is broadcast which produces on a color TV receiver two spaced images, each of a different color. When viewed through glasses having image-colored lenses, a threedimensional scene is perceived. On a black and white receiver, only a single image is produced.

Video display system creating both horizontal and vertical sync pulses from the disc time track

Abstract: The video display system described consists of a digital disc which can store at least three seismic cross sections and a high resolution TV monitor. The monitor can show a cross section of 480 traces with 500 five-bit samples per trace. The electronic parts of the system control the flow of data to and from a computer through an interface controller. A high-speed D/A converter changes the digital seismic data into an analog video signal, and an external core memory is used to ''''bridge'''' the various speeds with which data flow from one point to another in the system. A graphical input device can be used to draw zones on the displayed cross section. This system can be an integral part of a complete computer graphics system.

Design of a real-time central data acquisition and analysis system

Abstract: A computer system is described for real-time data acquisition and servicing of 40 asynchronous inertial guidance system test stations. Some data are received automatically from the small guidance system computers at a maximum rate of eight words per second. Other data are input manually at each station via a mode selector and several 16-position thumbwheel switches. The data are received, partially edited and stored all in real time, and retrieved and analyzed with the highest "time-availability" priority at the time of completion of the guidance system test. The analysis results determine further testing or repair actions for each guidance system. The central computer is a SEL 840-MP, a general-purpose 24-bit, 32K, 1.75-µs cycle-time machine with basic real-time monitor software. The special purpose system is implemented as a software/ hardware interface with the real-time monitor and the test station hardware. A key factor for the real-time data processing is the use of random access blocks on mass storage discs to greatly augment primary memory without seriously degrading total accessing time. This also frees "background" core for off-line programs running in a low-priority interruptable mode and for the analysis programs which do not operate in the real-time mode. A disc allocation and cataloging scheme is presented along with a hardware and software description.

Volumetric compensation through the machine controller

Abstract: Compensation is a cost effective method of correcting for machine tool systematic errors. Although controller manufacturers are providing increasingly more sophisticated compensation, they do not include for all geometric sources of error for the variety of 3and 5-axis configurations that exist today. A small number of comprehensive PC-based compensation systems exist, requiring hardware modifications and interface electronics to interact with the position control loop, which can be expensive and difficult to implement. This paper describes a general purpose error compensation system that is located and runs inside the machine controller. The system has been designed to run on a modem open architecture Computer Numerical Controller, namely an Osai UK series 10 controller. One of the facilities within this controller is a DOS Real Time Interface, which allows a user to develop custom applications that can run and communicate with various parts of the NC system in real time. Compensation software, based on a 5-axis geometric error compensation system produced at the University of Huddersfield, has been developed to run in the DOS real time environment. The system has been applied to three machine tools and the volumetric accuracy significantly improved. Requiring only a simple software installation, the system is also shown to be inexpensive, simple and fast to implement.

Digitization of ultrasonic images.

Abstract: The authors describe a method for digitizing diagnostic ultrasonic data using a system originally constructed for use with radioisotope scan data. A commercial ultrasonic unit drives the transducer and amplifies the preliminary echo signal. The output signals from the ultrasonic unit are fed to a programmable digital logic interface coupled to a 4,096-word memory. The data can then be transferred directly to a PDP-9 computer for data manipulation or to computer-compatible magnetic tape for permanent storage.

A multiprogramming, virtual memory system for a small computer

Abstract: The specific objective of this small computer system is to interface six to eight small graphical terminals to a large batch-processing computer. The small computer provides the graphical terminals with real-time processing for generating, editing and manipulating graphical or text files. The small computer passes along to the large computer requests for large tasks. Access to the data base in the large computer is provided. Another aspect of this objective is remote concentration. The terminals are connected to the small computer directly or through several DATA-PHONE® 103 data sets. The small computer is connected to the large computer through a single DATA-PHONE® 201 data set. This configuration reduces communication costs for a group of terminals located remotely from the large computation center.

Technical and human engineering problems in connecting terminals to a time-sharing system

Abstract: Today, an increasing number of computer systems are used interactively by their user communities. Interactive use of computers, involving more prolonged man-machine contact than non-interactive use, requires a well human engineered user-system interface. The interactive user's performance---his rate of doing work and his ability and desire to utilize system capability---is a sensitive function of the success of this human engineering. In turn, the computer system's effectiveness depends on achieving a satisfactory level of user performance with reasonable efficiency.

Orela Data Acquisition into Greater than 105 Channels through a Priority Multiplexer Operating on a Direct Memory Access and a Program Controlled Device Interface

Abstract: The Oak Ridge Electron Linear Accelerator (ORELA) facility includes a linear accelerator and a series of computers for real-time data acquisition and on-line analysis of the acquired data. The unique features of the data acquisition computers are the following: a word-addressed, fixed-head disk; a direct-memory access, four-channel priority multiplexer capable of a peak data rate of 25,000 events/sec per channel; and a program-controlled, subaddressed device interface. Operation of the word-addressed, fixed-head disk through software and hardware control allows the experimental events to determine which channels are to have their contents read into the core memory from the disk for updating, with a resulting theoretical maximnum average data rate of 11,000 events/sec. Trade-offs for future systems are possible between the hardware and software. Operation of the priority multiplexer is described briefly. A modified, TMC, 4096-channel time-of-flight analyzer allows control from the computer through the multiplexer. A pulse generating unit, mounted in a triple-width NIM module, operates through one channel of the program-controlled device interface to control a TMC time-of-flight analyzer and a sample changer. The sample changer operates in a feedback loop that is controlled by a computer program.

Mine roof support control system

Abstract: Mine roof supports have a fluidic logic control system for raising and lowering the supports and for advancing the supports in the form of a number of units one on each support. Each unit has a first OR gate which controls a first interface valve to cause the support to lower and advance itself, a second interface valve causing the support to rebrace itself controlled by a second OR gate interconnected with the first through an AND gate which receives inputs from the first OR gate and a sensor denoting that the advance has been completed, an AND gate receiving inputs from a sensor denoting that the support is rebraced and from the second OR gate to provide an input for the first OR gate of the next unit and a reset signal which is passed through a delay restrictor to reset the first OR gate of the support.

Objetos de Aprendizagem para o Letramento Informacional

Abstract: This work presents the fundamental points for the production of Learning Objects (LO), as well as the results of a survey about the perception of students about the production of these resources. The production of LOs requires knowledge involving content issues, teaching learning and expertise. The results show that participants recognize the importance of Learning Objects to enhance teaching-learning process and demonstrate willingness and motivation during the production process, but also highlight the need to improve the interface of the software to make it more friendly and intuitive.

Interface circuits for a pcm time multiplex switching center

Abstract: In a switching center controlled by two computers operating, for example, in the load-sharing mode, each of said computers has an access to each peripherical unit through an interface circuit. This interface has two functions:

Analog-to-digital system

Abstract: A HEWLETT-PACKARD 2115 ANALOG-TO-DIGITAL CONVERTER FOR USE WITH THE SURFACE DYNAMICS PROFILOMETER IN CONDUCTING PAVEMENT QUALITY TESTS IS DESCRIBED. AFTER A DISCUSSION OF THE A/D PROBLEM, DETAILED DESCRIPTION IS PROVIDED FOR AN INTERFACE AND PATH LOGIC MODULE BUILT BY PROJECT PERSONNEL TO INTERFACE EXTERNAL SIGNS WITH THE 2115, THE A/D AND TAPE WRITE PROGRAMS NECESSARY FOR SYSTEM OPERATIONS, AND THE OPERATING AND DATA VALIDATION PROCEDURES REQUIRED TO USE THE EQUIPMENT. ADDITIONAL DIAGRAMS AND PROGRAM LISTINGS PROVIDE COMPLETE DOCUMENTATION OF THE SYSTEM. THE A/D SYSTEM IS FULLY COMPATIBLE WITH THE SDS 930 USED IN THE INITIAL STAGES OF THE PROJECT ON PAVEMENT ROUGHNESS MEASUREMENT INAUGURATED IN 1963. CURRENT ANALYSIS PROGRAMS THAT RUN ON A CDC 6600 OR IBM 360/50 CAN USE THESE DATA WITHOUT PROGRAM CHANGES. /AUTHOR/

Automatic Data Collection for Mossbauer Effect Spectroscopy

Abstract: An automatic data collection system for four Mossbauer effect experiments has been implemented by Argonne National Laboratory utilizing a small general purpose digital computer and a special purpose interface. This system, being characteristic of open-loop, on-line systems, permits maximum utilization to be made of interface hardware to fully automate data collection from four simultaneous experiments, while the computer is in a "halt" condition or being utilized for background processing. Extensive consideration was given in the design of this system to achieve the most advantageous balance of hardware and software.

Mechanical switch interface

Abstract: An interface is provided to allow signals from a relatively lowspeed mechanical or electromechanical system to be used in a high-speed electronic system. Each of the input signals is fed to a rectifying circuit and then the signal is transmitted to a gated flip-flop. The output of the gated flip-flop is coupled with an inhibiting signal and applied to an output inverter. The output is a high-speed, small rise-time signal usable in electronic computing or control systems.

Sample-hold circuit

Abstract: A sample-hold circuit which provides an interface between the electronic and mechanical portions of a missile wherein it is required that a signal be held for a finite time comprising two complete sample-and-hold circuits in series.

Application of the Northrop Rotational Simulator to Helicopters and V/ STOL Aircraft (User's Guide)

Abstract: : The purpose of the document is to suggest guidelines to be used in developing software interface computations so as to effectively integrate the pilot and mathematical vehicular representation to the Northrop rotational simulator. A description of all key elements and their performance and operating characteristics is included. Past uses and projected future uses are also given. Some validation methods are described with suggestions for their use. Suggested interface mechanizations are given which provide effective visual and motion stimuli compatible with sensory characteristics. A rationale for the use of motion is included. A method is outlined which assists the user in assessing the probability of success in any desired simulation and preparation of an effective experimental design.