Lecture 1: Introduction
What is exactly an embedded system => Real-time system that interfaces with external
What then exactly is a real-time system => Computer system that interacts with external
Examples: Toaster, braking system, traffic light system (except in Montreal), soda
Question: What about air conditioners, refrigerators, thermometers…?
Types of Embedded systems – signal processing, mission critical, distributed
Embedded real-time challenges: timeliness, predictability, event drivers, reliability,
distribution, dynamics, concurrency, scalability, communication, synchronization,
What is difference between an O/S and an RTOS?
-an RTOS is an O/S
-an O/S also interfaces H/W below with S/W applications above
-an RTOS additionally allows user access to O/S low-level system services
RTOS examples: PSOS, Lynos, ALX, QNX, VRTX, Linux, Unixware, Windows CE and
NT, RTMX…but by far the world leader in RTOS development and usage: VxWorks by