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CS269: HW/SW Engineering of Embedded Systems, Winter02
Constraints
•Two mechanisms are supported to specify constraints:
•   1. Propositions over temporal orders of states
–execution is a sequence of states
–specify constraints using linear temporal logic
–good for scheduling constraints, e.g.
•“if process P starts to execute a statement s1, no other process can start the statement until P reaches a statement s2.”  
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•   2. Propositions over instances of transitions between states
–particular transitions in the current execution: called “actions”
–annotate actions with quantity, such as time, power.
–specify constraints over actions with respect to the quantities
–good for real-time constraints, e.g.
•“any successive actions of starting a statement s1 by process P must take place with at most 10ms interval.”