Raj S. Mitra

Hardware software partitioning using genetic algorithm

Hardware software co-design is gaining importance with the advent of CAD for embedded systems. A key phase in such designs is partitioning the specification into hardware and software implementation sets. The problem being combinatorically explosive, several greedy search algorithms have been proposed for hardware software partitioning. In this paper, we model the hardware software partitioning problem as a Constraint Satisfaction Problem (CSP), and present a genetic algorithm based approach to solve the CSP in order to obtain the partitioning solution.

A new algorithm for implementation of design functions by available devices

In CAD systems, it is often required to implement desired behaviors by some available device. The selection of the device that can implement the behavior, and the required interfacing, is usually done by human experts. The interface consists of transformations that may have to be performed on the inputs and outputs of the device. This paper describes an approach to automatically derive the specifications of the devices interface. For sequential circuits, the behaviors are often represented as FSMs, and hence the task is to determine whether the FSM of the desired function can be contained in the FSM of the device, subject to the transformations of the interface. A related objective, addressed in this paper, is to model the behaviors of complex devices in a way that facilitates the analysis.

Knowledge representation in MICKEY: an expert system for designing microprocessor-based systems

This paper presents the knowledge representation schemes adopted in MICKEY, a knowledge based system for designing microprocessor based systems. MICKEY is essentially a hybrid expert system, using rules and procedures for achieving the different design tasks. We briefly describe the hierarchy of tasks in this problem domain, and emphasize on the refinement paradigm, constraint propagation, conflict resolution and task management strategies adopted in MICKEY. Next, we dwell upon the different knowledge sources and their functions, with respect to the particular design domain. Finally, we present an industrial design, achieved by MICKEY, to demonstrate its applicability.

Interface synthesis for embedded applications in a codesign environment

In embedded systems, programmable peripherals are often coupled with the main programmable processor to achieve the desired functionality. Interfacing such peripherals with the processor qualifies as an important task of hardware software codesign. In this paper, three important aspects of such interfacing, namely, the allocation of addresses to the devices, allocation of device drivers, and approaches to handle events and transitions have been discussed. The proposed approaches have been incorporated in a codesign system MICKEY. The paper includes a number of examples, taken from results synthesized by MICKEY, to illustrate the ideas.

Rapid prototyping of microprocessor-based systems

In order to design microprocessor-based application systems, several cooperating tasks have to be performed, such as the design of the skeletal process, hardware-software partitioning, design of the hardware configuration, interface design for the selected I/O devices, and generation of application specific software code. This paper presents an integrated CAD framework for automatically designing such hardware configurations and software code, to achieve the functionalities of the desired application. The design of an ECG monitoring system has been presented to illustrate the efficacy of the system.

Hardware-software partitioning: a case for constraint satisfaction

A key task in mixed hardware-software embedded systems design is partitioning the design functions into hardware- and software-implementable sets. The authors present an algorithm for solving the hardware-software partitioning problem and evaluate the performances of different search control heuristics.

Asynchronous implementation of synchronous Esterel specifications

The synchrony hypothesis of Esterel demands the generation of a single monolithic FSM from the specifications. However for large specifications, the size of this FSM can prove to be inhibitively large. In this paper, we propose a practical solution to this problem, which generates separate FSMs for each of the concurrent instructions. We also enumerate the deviations in semantics due to this translation algorithm so that the user is aware of the executable semantics that he should expect.

A consistent labeling approach to hardware software partitioning

Design of embedded systems has brought the discipline of hardware software codesign into focus. A major task of such codesign activity is partitioning the functions into hardware and software implementation sets. In this paper, we propose an algorithm which performs such partitioning and also allocates the functions to modules. The task has been formulated as a consistent labeling problem. To deal with the combinatorial nature of the problem, a number of heuristics have been proposed and their relative performances have been evaluated experimentally. The algorithm has been applied to solve several design problems.

Design of microprocessor-based systems: a knowledge-based approach

The widespread use of microprocessors in industrial applications such as process control, data logging, monitoring, etc., demand that the design of such systems be automated. Algorithmic methods are inadequate for this task, as knowledge from several sources need to be combined to produce the resulting design. In this paper the authors present a knowledge-based approach to the design of such systems, which includes the design of the hardware configuration as well as the application software. The knowledge requirements and the functional modules of the design task are elicited, and practical designs are demonstrated. >

An overview of MICKEY: A knowledge-based hardware-software codesign framework for microprocessor-based systems

We present the architecture of a second-generation expert system for the automated design of microprocessor-based systems. A novel feature is the integration of a device handbook knowledge base with a shallow expert system, to provide resilience and deep reasoning capability. The design tasks, knowledge sources, behaviour modelling scheme, behaviour mapping algorithms, and inter-layer communication are briefly described.