Transcript Document
Replacing Hardware With Software Analysis and simulation of existing hardware using Discrete Event System Specification. By: Philip Felber Aman Gupta Imaduddin Mohammed Kwadwo Adomako November 27, 2001 Prepared for Dr. James Stine ECE 587 Hardware / Software CoDesign Illinois Institute of Technology Replacing Hardware With Software Philip – Set the scene 11/27/2001 ECE587 Replacing Hardware With Software 2 Replacing Hardware With Software Large apartment buildings built in the seventies (before embedded computers) were equipped with custom electronic security and control systems. 11/27/2001 ECE587 Replacing Hardware With Software 3 Replacing Hardware With Software Apartment Security Panel Security On Package (loudspeaker) Security Package Notification Fire Alarm Emergency 11/27/2001 ECE587 Replacing Hardware With Software OFF ON Security Key Switch 4 Replacing Hardware With Software System components Apartment security panels (in each unit) Central communications controller Alarm “readout” at front desk Keypad terminal at receiving room 11/27/2001 ECE587 Replacing Hardware With Software 5 Replacing Hardware With Software Today it’s increasingly hard to find both repair parts and technicians who understand this antiquated hardware. 11/27/2001 ECE587 Replacing Hardware With Software 6 Replacing Hardware With Software With DEVS as a framework, this study analyzes and simulates a legacy security system and assesses opportunities to replace certain hardware components with software. 11/27/2001 ECE587 Replacing Hardware With Software 7 Replacing Hardware With Software Aman – DEVS 11/27/2001 ECE587 Replacing Hardware With Software 8 Replacing Hardware With Software The Discrete Event System Specification (DEVS) environment is a system based simulation tool that provides expandability with modular and hierarchical features and flexibility. DEVS framework consists of: real system model simulator experimental frame These are related by two relations: modeling relation simulation relation 11/27/2001 ECE587 Replacing Hardware With Software 9 Replacing Hardware With Software Experimental frame Source System Simulator Simulation Modeling Model Relation 11/27/2001 Behavior database ECE587 Relation Replacing Hardware With Software 10 Replacing Hardware With Software In the DEVS formalism, there are two models to be specified: Atomic Model from which larger models are built Coupled Model 11/27/2001 ECE587 Replacing Hardware With Software 11 Replacing Hardware With Software Atomic Model contains Set of input ports Set of output ports Set of state variables and parameters Internal transition External transition Output function 11/27/2001 ECE587 Replacing Hardware With Software 12 Replacing Hardware With Software Coupled Model must contain Set of components Set of input ports Set of output ports Coupling specifications 11/27/2001 ECE587 Replacing Hardware With Software 13 Replacing Hardware With Software Imaduddin – Specific analysis 11/27/2001 ECE587 Replacing Hardware With Software 14 Replacing Hardware With Software Modeling with DEVS Outline the functions. Identify the Input Events. Input Events States: Output Events Key Position Identify Internal States. Door Position Identify Output Events Intrusion Emergency Fire Package 11/27/2001 ECE587 Replacing Hardware With Software 15 Replacing Hardware With Software Hierarchical Model of the System Coupled Model Central Communication Control Alarms to front desk Coupled Model Apartment Panel Package Notification from Receiving room Atomic Model Security Alarm Emergency Alarm Fire Alarm Atomic Model Key Door Atomic Model 11/27/2001 ECE587 Replacing Hardware With Software 16 Replacing Hardware With Software Simulation Start Initialize States Event Driven Program Wait For Input Event Modular Multithreaded NO Input Event Occurs YES Process the request Give output 11/27/2001 ECE587 Replacing Hardware With Software 17 Replacing Hardware With Software For Example: Input Event Package Arrival PkgReceive Module Central Communication Control Module AptPanel Module Output Event Set package Light ON State---------------- Pkg Before Input Event NO After Input Event -Yes 11/27/2001 ECE587 Replacing Hardware With Software 18 Replacing Hardware With Software Kwadwo – Close the deal 11/27/2001 ECE587 Replacing Hardware With Software 19 Replacing Hardware With Software What we have accomplished Analysis of the system with DEVS formalism. Choose which components we can replace with software. Simulate the system. The DEVS simulation may develop into the actual production program. 11/27/2001 ECE587 Replacing Hardware With Software 20 Replacing Hardware With Software Advantages of our Design Our design makes the system faster. It provides room for further additions to the system. It is easier to maintain. 11/27/2001 ECE587 Replacing Hardware With Software 21 Replacing Hardware With Software What’s yet to be done? Complete the simulation program of the system in java. Complete documentation of the project. 11/27/2001 ECE587 Replacing Hardware With Software 22 Replacing Hardware With Software Summary Some parts of legacy hardware systems are candidates for emulation by software running on general purpose microprocessors. DEVS may be a useful tool for analysis and simulation. The DEVS simulation may develop into the actual production program. 11/27/2001 ECE587 Replacing Hardware With Software 23 Replacing Hardware With Software Where To Get More Information Zeigler, Praehofer, and Kim: Theory of Modeling and Simulation: Integrating Discrete Event and Continuous Complex Dynamic Systems, Academic Press, 2000. Search the ‘NET’ for DEVS. www.ece.iit.edu/~pfelber/devs/ibms/ 11/27/2001 ECE587 Replacing Hardware With Software 24