These are lecture notes from my Computer Science course.
For learning about real-time systems, I recommend Real-Time Systems and Programming Languages.
- Hard real-time: Systems where it is imperative that responses occur within the required deadline, e.g. a flight control system
- Soft real-time: Systems where it would be useful to know the data immediately, but the data can still be useful after deadlines (degrading)
- Firm real-time: Similar to hard real-time. Soft real-time but there’s no benefit to late delivery. Different to hard real-time in that in hard real-time old data has a negative use, with firm real-time it just has zero use.
- Time-aware: System that makes an explicit reference to time
- Reactive: Control systems, systems that must react (produce output) within deadline based on input. Subject to jitter – variability in input/output read/write.
- Time-triggered: computation is triggered by passage of time, e.g. a periodic activity. Polling
This entry was posted in lecture
. Bookmark the permalink