Showing papers on "Data flow diagram published in 1970"

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.

The controls automation system

Abstract: This paper discusses the specifications, programming implementation, and use of a design automation system that can be used in the development of any computer having read-only storage (ROS) controls.This system, called the Controls Automation System (CAS), designed concurrently with the IBM System/360 was used to aid in the design and construction of Models 40, 50, 65 and 67. The current version of CAS is used by IBM to aid in the design of all systems with ROS controls.The system has been found particularly attractive for the simulation of microprogram-controlled machines although its use is not restricted to them. The newly developed elements of this system are: 1) a programming language for describing the data flow of a machine; 2) a program for translating a variety of microprogramming languages into a common one; and 3) a set of computer programs enabling the machines operation to be simulated on an IBM 7090/1401 computer.In addition, CAS has facilities for preparing microprogram design records in a form that is easy to use and understand, and it provides for rapid updating of design records.This paper was presented at the Sixth Annual Symposium on Switching Theory and Logical Design at the U. of M., Oct. 1965.The paper discussions on an elementary level the systems objectives and organization of CAS. The CAS machine description language is explained followed by the microprogram description. Inserted directly behind the microprogram description is the following rather interesting quote "By Defining the Microprogram and the Machine Description in the two simple specialized languages described here, the Controls Automation System has been able to accomplish what has previously been done by a single, relatively complex language". This reference to APL - and Gormon and Anderson's "A Logic Design Translator." presented at the 1962 FJCC.The paper than concludes with CAS output examples and details of the other CAS design aids. Here is the first explanation of the use of the funny little boxes encountered. Not as complete in detail as one might like, but an interesting paper if one should need an overview of CAS.

An approach to the simulation of control systems using the digital computer

Abstract: A technique is described for the digital simulation of a wide range of open- and closed-loop control systems. The method allows the determination of the time domain performance (e.g. the step response) of a system containing any series combination of simple or quadratic leads, lags and pure integrations. A computer program has been developed which will produce the time domain performance of a system by teletyping into the computer the relevant constants of that system. The resulting response can be obtained in the form of a print out for permanent accurate record or as a graphical display on a cathode ray oscilloscope or on an XY recorder. The method is thus particularly useful in the interactive computer-aided design of control systems. The method has two principal advantages over conventional analogue computer methods. Firstly accuracy can be traded directly for computational time and thus initial tests in design optimisation can be made quickly, whilst final designs may be checked to an accuracy far greater than that obtainable on any analogue computer simply by using a longer computational time. The second advantage is that structural alterations can be made to the model of the system under test merely by teletyping the new data into the computer. Analogue computers must be repatched and potentiometers set with the attendant possibility of errors being made. The article contains a flow diagram and detailed listing of a FORTRAN program based on the technique described and adapted to the limited storage capacity (4k 12-bit words) of a PDP 8 computer with associated cathode ray display.

On Data Flow Testing Strategy

Abstract: For the studies on the data flow oriented selection of test data [4], [5], [6], [8], the selection strategies are all based on the intuition that an incorrect definition could never be uncovered if its use is not tested. In this paper, we are proposing another data flow oriented selection strategy based on the intuition that errors tend to be clustered together and are more likely to be associated with the improper or bad programming practice. It has been found that our strategy is complementary to [4], [5], [6] and [8], and can be incorporated at nominal overheads with Laski and Korel's strategy [5].

A data flow controller and refresh memory for a computer display system.

Abstract: This thesis presents the design and implementation of a digital controller and high speed refresh memory for a cathode ray tube (CRT) display terminal. The specific function of this device was the control of and the £3J pply of data to graphical and alphanumeric display generators that were also in the development stages. The system for CRT display was to be used in conjunction with a Digital Equipment Corporation (DEC) PDP8/S computer. The slow cycle speed and single stream processing of the PDP8/S made the development of control and refresh circuitry necessary to free the computing facilities of the PDP8/S for programmed data processing necessary for the effective use of CRT display equipment. The device described in this thesis was constructed and interfaced to the PDP8/S through the standard input-output (I/C) facilities of the PDP8/S which "sees" the device as one of its peripherals. Thus the PDP8/S has been fitted with CRT display facilities over which it exerts indirect control through the logic presented in this thesis. The PDP8/S is, therefore, not operating as a dedicated computer but is free to per­ form any other program tasks and I/C to its other peripherals while maintaining its CRT display in full operation. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.

Digital calculation of optimum controls for time-varying linear multivariable systems. realisation of contraction-mapping algorithm

Abstract: The paper considers the digital-computer implementation of the contraction-mapping algorithm, which is used to solve the integral equations defining the optimal control for time-varying multivariable systems with quadratic cost functions. A completely time-varying problem is first considered, and a general flow diagram for the digital-computer solution is given, together with a detailed description of each block of the flow diagram including an estimate of the storage-location requirements. As an illustration, an example problem is examined in detail and a complete flow diagram and the program listing of the digital-computer solution are given. Results are then presented which illustrate the digital-computer iterates and compare the actual and predicted measures of convergence.

Graph program simulation

Abstract: This reports the simulation of a parallel processing system based on a directed graph representation of parallel computations. The graph representation is based on the model developed by Duane Adams in which programs are written as directed graphs whose nodes represent operations and whose edges represent data flow. The first part of the report describes a simulator which interprets these graph programs. The second part describes the use of the simulator in a hypothetical environment which has an unlimited number of processors and an unlimited amount of memory. Three programs, a trapezoidal quadrature, a sort and a matrix multiplication, were used to study the effect of varying the relative speed of primitive operations on computation time with problem size. The system was able to achieve a high degree of parallelism. For example, the simulator multiplied two n by n matrices in a simulated time proportional to n.

A Chemical Machine Implementing Autonomous Systems

Abstract: Classical planners, which automatically generate plans to be executed as a sequence of primitive actions cannot follow their actual execution because they cannot compare and modify its behaviour continuously using sensor data flow. On the other hand, autonomous systems need to interact with the environment because they have an incomplete knowledge about it. So, the planner doesn't pretend to generate explicitly all the actions. In this paper we propose an alternative way to design and build an autonomous system introducing the metaphor of biochemical machine. We think of the whole system as a family of behaviours, each implementing a set of actions which specify, at each step, the most appropriate response to a perceptual issued stimulus. Moreover, each behaviour is equipped with appropriate receptors which can cause its inhibition, or suspension, if it is not currently requested. Later, the behaviours can be resumed. Such an inhibition schema is directly driven by the system itself using sensor data and the knowledge it has about its state.