1. SE-3910 Real-time Systems Week 1, Class 2 – Fine Print – Web page available – Review Quiz 0 – What is a Real-Time Embedded System? Embedded & Real-Time Systems Microcontrollers vs. Microprocessors Impact SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling, Some from Dr. Hornick, etc. 1

2. CPU Layout (1) SE-1021 Dr. Josiah Yoder Slide style: Dr. Hornick 2

3. CPU Layout (2) SE-1021 Dr. Josiah Yoder Slide style: Dr. Hornick http://en.wikiversity.org/wiki/Computer_Architecture_Lab/WS2007/pipeline 3

4. Terminology Definition – A brief description of a word’s use SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 4

5. Terminology Real-Time –responding as rapidly as required by the user or the process being controlled. - Random House Dictionary (Abbrev.) Embedded System – A combination of hardware & software to perform a specific function -Dr. Schilling’s slides –Part of a larger system – the “computational engine” –Often real-time SE-1021 Dr. Josiah Yoder Slide style: Dr. Hornick 5

6. SE-1021 Dr. Josiah Yoder Slide style: Dr. Hornick Slide copied from Dr. Schilling’s Slides 6

7. TABLE I, TABLE II SE-1021 Dr. Josiah Yoder Slide style: Dr. Hornick 7

8. What is a system? System A mapping from a set of inputs to outputs SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 8

9. Example: Weather Monitor SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 9

10. Real-Time System Terminology Soft – Not destroyed by failure to meet response time Hard – Destroyed by failure to meet a single deadline Firm – Destroyed by failure to meet multiple deadlines SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 10

11. Virtual Plant Tour Stamping – http://www.youtube.com/watch?v=bYCc3toOHdc http://www.youtube.com/watch?v=bYCc3toOHdc Vision – http://www.youtube.com/watch?v=QXbpxHeeBA E http://www.youtube.com/watch?v=QXbpxHeeBA E SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 11

12. Got this far on first day SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 12

13. Discussion On your own: Write which kind of real-time system is being used With your partner, discuss & fill in the explanations SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 13 SystemClassificationExplanation Video Surveillance System for Car Dealership Laser welding robot to construct car frames 2 player air hockey game on game console

14. Event – A jump in the program counter Synchronous – Predicatable. Scheduled. In sync with other events Asynchronous – Unpredictable. Unscheduled. External requests Aperiodic – No fixed period, asynchronous Sporadic – Extremely infrequent and aperiodic Punctual – Neither early nor late SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 14

15. Digibot Circuitry A deterministic system SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 15

16. Five Misconceptions (paraphrased from Laplante and Ovaske) Real-time Systems are fast All you need is – a real-time OS – a rate-monotonic scheduler – lots of scheduling theory We’ve figured out how to make real-time systems SE-3910 - Dr. Josiah Yoder Slide style: Dr. Hornick Much Material: Dr. Schilling 16