Hardware/Software Co-Design

by Asawaree Kalavade and Edward A. Lee

Proceedings of the IFIP International Workshop on Hardware/Software Co-Design
Grassau, Germany
May 19-21, 1992
Appeared In: Proceedings of the First Intl. Workshop on Hardware/Software Codesign, Color ado, Sept. 1992.



Ptolemy is an environment for simulation and prototyping of heterogeneous systems. By supporting the co-existence and interaction of different models of computation, Ptolemy facilitates mixed-mode system simulation, specification, and design as well as generation of DSP assembly code from a block diagram description of the algorithm. These features render Ptolemy suitable for hardware/software codesign. This case study demonstrates the use of Ptolemy for hardware/software co-design. The test case is a telephone channel simulator that generates EIA-specified channel impairments for voice-band data modem testing - where the hardware comprises cu stom hardware coupled to programmable DSP chips, and the software is the code running on these programmable processors. The codesign methodology using Ptolemy is illustrated via the development and evaluation of a sequence of designs for this telephone channel simulator. These designs address multiprocessor communication, scheduling and code partitioning issues, as well as issues of system-level hardware/software partitioning of functionality.