Soonhoi Ha

Existent hardware-software (HW-SW) codesign tools mainly focus on HW-SW cosimulation to build a virtual prototyping environment that enables software design and system verification without need of making a hardware prototype. Not only HW-SW cosimulation, but also HW-SW codesign methodology involves system specification, functional simulation, design-space exploration, and hardware-software cosynthesis. The PeaCE codesign environment is the first full-fledged HW-SW codesign environment that provi

Four scheduling strategies for dataflow graphs onto parallel processors are classified: (1) fully dynamic, (2) static-assignment, (3) self-timed, and (4) fully static. Scheduling techniques valid for strategies (2), (3), and (4) are proposed. The focus is on dataflow graphs representing data-dependent iteration. A known probability mass function for the number of cycles in the data-dependent iteration is assumed, and how a compile-time decision about assignment and/or ordering as well as timing

Scheduling dataflow graphs onto processors consists of assigning actors to processors, ordering their execution within the processors, and specifying their firing time. While all scheduling decisions can be made at runtime, the overhead is excessive for most real systems. To reduce this overhead, compile-time decisions can be made for assigning and/or ordering actors on processors. Compile-time decisions are based on known profiles available for each actor at compile time. The profile of an acto

Hardware/software codesign involves various design problems including system specification, design space exploration, hardware/software co-verification, and system synthesis. A codesign environment is a software tool that facilitates capabilities to solve these design problems. This paper presents the peace codesign environment mainly targeting for multimedia applications with real-time constraints. Peace specifies the system behavior with a heterogeneous composition of three models of computati

A noble model-based programming environment of embedded software for MPSoC is proposed. By defining a common intermediate code (CIC), it separates modeling of the software and implementation optimized for target architecture. It also allows us to use diverse models for initial specification. Another feature is to provide multi-phase debugging capabilities: at the modeling stage, at the code generation stage, and at the simulation stage. Preliminary experiments with a Divx player confirm the feas

Scheduling of dataflow graphs onto parallel processors consists of assigning actors to processors, ordering the execution of actors within each processor, and firing the actors at particular times. Many scheduling strategies do at least one of these operations at compile time to reduce run-time cost of scheduling activities. In this thesis, we classify four scheduling strategies, (1) fully dynamic, (2) static-assignment, (3) self-timed, and (4) fully static. These are ordered in decreasing run-t

Scheduling strategies for a multiprocessor DSP (digital signal processor) are classified into four types: fully dynamic, static-assignment, self-timed, and fully static. The concept of static scheduling (self-timed or fully static) is extended to handle nondeterministic actors in the proposed quasi-static scheduling. Quasi-static scheduling minimizes run-time overhead with increased compilation complexity, and is thus adequate for signal processing applications. The proposed scheme is applicable