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.
ABSTRACT
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.