RTMPL: A structured programming and documentation utility for real-time multiprocessor simulations

The NASA Lewis Research Center is developing and evaluating experimental hardware and software systems to help meet future needs for real time simulations of air-breathing propulsion systems. The Real Time Multiprocessor Simulator (RTMPS) project is aimed at developing a prototype simulator system that uses multiple microprocessors to achieve the desired computing speed and accuracy at relatively low cost. Software utilities are being developed to provide engineering-level programming and interactive operation of the simulator. Two major software development efforts were undertaken in the RTMPS project. A real time multiprocessor operating system was developed to provide for interactive operation of the simulator. The second effort was aimed at developing a structured, high-level, engineering-oriented programming language and translator that would facilitate the programming of the simulator. The Real Time Multiprocessor Programming Language (RTMPL) allows the user to describe simulation tasks for each processor in a straight-forward, structured manner. The RTMPL utility acts as an assembly language programmer, translating the high-level simulation description into time-efficient assembly language code for the processors. The utility sets up all of the interfaces between the simulator hardware, firmware, and operating system

Design, testing, and delivery of an interactive graphics display subsystem

An interactive graphics display system was designed to be used in locating components on a printed circuit card and outputting data concerning their thermal values. The manner in which this was accomplished in terms of both hardware and software is described. An analysis of the accuracy of this approach is also included

MINDS: A microcomputer interactive data system for 8086-based controllers

A microcomputer interactive data system (MINDS) software package for the 8086 family of microcomputers is described. To enhance program understandability and ease of code maintenance, the software is written in PL/M-86, Intel Corporation's high-level system implementation language. The MINDS software is intended to run in residence with real-time digital control software to provide displays of steady-state and transient data. In addition, the MINDS package provides classic monitor capabilities along with extended provisions for debugging an executing control system. The software uses the CP/M-86 operating system developed by Digital Research, Inc., to provide program load capabilities along with a uniform file structure for data and table storage. Finally, a library of input and output subroutines to be used with consoles equipped with PL/M-86 and assembly language is described

Debugging real-time software in a host-target environment

A common paradigm for the development of process-control or embedded computer software is to do most of the implementation and testing on a large host computer, then retarget the code for final checkout and production execution on the target machine. The host machine is usually large and provides a variety of program development tools, while the target may be a small, bare machine. A difficulty with the paradigm arises when the software developed has real-time constraints and is composed of multiple communicating processes. If a test execution on the target fails, it may be exceptionally tedious to determine the cause of the failure. Host machine debuggers cannot normally be applied, because the same program processing the same data will frequently exhibit different behavior on the host. Differences in processor speed, scheduling algorithm, and the like, account for the disparity. This paper proposes a partial solution to this problem, in which the errant execution reconstructed and made amenable to source language level debugging on the host. The solution involves the integrated application of a static concurrency analyzer, an interactive interpreter, and a graphical program visualization aid. Though generally applicable, the solution is described here in the context of multi-tasked real-time Ada* programs

On Testing Quantum Programs

A quantum computer (QC) can solve many computational problems more efficiently than a classic one. The field of QCs is growing: companies (such as DWave, IBM, Google, and Microsoft) are building QC offerings. We position that software engineers should look into defining a set of software engineering practices that apply to QC's software. To start this process, we give examples of challenges associated with testing such software and sketch potential solutions to some of these challenges.Comment: A condensed version to appear in Proceedings of the 41st International Conference on Software Engineering (ICSE 2019

A Simulator for LLVM Bitcode

In this paper, we introduce an interactive simulator for programs in the form of LLVM bitcode. The main features of the simulator include precise control over thread scheduling, automatic checkpoints and reverse stepping, support for source-level information about functions and variables in C and C++ programs and structured heap visualisation. Additionally, the simulator is compatible with DiVM (DIVINE VM) hypercalls, which makes it possible to load, simulate and analyse counterexamples from an existing model checker