Summary: | 碩士 === 國立中正大學 === 資訊工程研究所 === 90 === Increase in system complexity has made embedded software a very important part
of an embedded system. It has necessitated further research on how a complex,
real-time, embedded software can be designed automatically and correctly. Enhancing
recent advances in this research, we propose a Time-Memory Scheduling (TMS)
method for formally synthesizing and automatically generating code for real-time embedded
software, using the Colored Time Petri Nets (CTPN) model. Our method
extends previous work in three ways: (1) by allowing the specification of temporal
constraints in the system description to model real-time behaviors of software, (2) by
allowing the specification of colored tokens in the system description to model different
memory usages by data-types, and (3) by proposing an extended algorithm to
schedule the enhanced system model and generate static code. A real-time embedded
software, which is specified by a set of CTPN, is scheduled using TMS such that the
schedules satisfy both limited embedded memory requirements and all real-time with
task precedence constraints. Finally, a embedded software program is generated in
the C programming language using the valid TMS schedules. Through a real-world
example on the ATM Virtual Private Network server, we illustrate the feasibility and
advantages of the proposed TMS method for synthesizing embedded real-time software.
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