Synthesis of real-time embedded software with local and global deadlines

Abstract

Current methods cannot synthesize real-time embedded software applications when the global deadline of a task is shorter than the total of all local deadlines along a critical path in a task. This creates unnecessary modeling limitations which directly affect the types of systems synthesizable. We propose a quasi-dynamic scheduling algorithm for simultaneously guaranteeing both local and global deadlines, while satisfying all precedence constraints among subtasks and among tasks. Through this scheduling procedure, we are able to formally synthesize real-time embedded software from a network of real-time Petri net specifications. Application examples, including a driver for the master/slave role switch in Bluetooth wireless communication devices, are given to illustrate the feasibility of the scheduling algorithm.