Showing papers on "Application software published in 1967"

Design and Use of Fault Simulation for Saturn Computer Design

Abstract: A system of IBM 7090 Data Processing System computer programs was developed for the purpose of normal and/or fault simulation of the Saturn computer. This paper will describe the design of the simulator and cite several applications in the development of the Saturn computer. The architecture, plus several important characteristics of the simulator, are presented. These include the Design Automation input interface, the logic selection procedure, failure injection, the compilation procedure, logical simulation and functional simulation. The ability to simulate up to 4000 Saturn instructions in either normal and/or fault environments (up to 33 faults per IBM 7090 run) will be demonstrated. Simulation of single, multiple, solid or intermittent faults, plus an automated statistical analysis of intermittent fault simulation results, will be presented. The IBM 7090 execution time of a compiled logic simulator can be prohibitive. To minimize running time several programming techniques were utilized, including logic block ordering (to allow single pass simulation), parallel fault simulation, stimulus bypassing, and functional simulation. These techniques are described. Several special forms of simulator output were developed. The use of this output and the applications of the simulator are presented, including design verfication, test program evaluation, generation of a test point catalog, disagreement detector network evaluation, disagreement detector placement, intermittent failure analysis.

Reliability Aspects of the Variable Instruction Computer

Abstract: This paper is intended to show how the unique features of the Variable Instruction Computer (VIC) make it valuable for applications requiring high reliability. By careful choice of components, use of error-checking circuits, and selected application of redundant hardware, the basic unextended reliability of the VIC is comparable with the state-of-the-art. This is verified by a standard MIL-HDBK-217 type of analysis. The variable instruction technique is briefly described by use of a block diagram. The method for extending reliability by use of variable instructions is explained and an example is given. The concept of algorithm change to achieve controlled graceful degradation is discussed. An analysis of a typical application of this technique is given and extensions of the variable instruction concept to more advanced reliability requirements are discussed.

New Instructional Potentials of Information Technology

Abstract: Two types of instructional interactions between a computer system and a student are in current use. In one type, the computer is assigned the dominant role in controlling the interaction. In the other, the student is given considerable freedom to manipulate the computer system throughout the interaction. Instructional systems exemplifying both types of interactions are described.