By Andrew Gliga Cs 147

1. Embedded Systems By Andrew GligaCs 147

2. What are Embedded Systems? • Similar to real computers • They have CPU, memory, I/O • Though they have limited tasks • Can only do specific things that they are designed for • No specific definition for Embedded Systems, some systems have one task, others have hundreds. Some have GUI, some do not even have a mode of interaction

5. What uses Embedded Systems? • Cars, Airplanes, Coffee Machines, MP3 players, cellphones • Basically any machine that needs to perform certain tasks • The Embedded Systems in these machines controls certain aspects, such as fuel injection, pilot controls, speedometers, and dispensing Coffee

6. History of Embedded Machines • Computers in the 1940's were too large and expensive to be used in portable tasks, even though they could perform simple tasks. • Over time though, with smaller and smaller computers, they could be created for specific tasks

7. More History • Charles Stark Draper developed the first modern Embedded Machine for the Apollo Spacecraft, called the Apollo Guadance computer that helped make the Moon landing possible.

8. Even More History • With the introduction of the Microprocessor, Embedded Machines were able to take smaller and smaller forms. • This allows smaller and lighter machines that control many of our devices today, such as our Cell phones, or MP3 players

9. Characteristics • They can only be used for specific tasks, not general tasks • They run with limited resources • They can also be a part of a larger system and used as a subsystem • For example: a car is the larger system, while the Embedded System is a subsystem of the car

10. Microcontrollers • Microcontrollers is what controls the embedded system • Unlike Microprocessors, they include memory and I/O. In a sense, they are like a mini computer • They implement AND, OR, XOR, NOT gates • Extremely compact and cheap

12. Microcontrollers are Small

13. Aspects of Microcontrollers • Watchdog timers • They generally keep an eye on the system. • When an error occurs in the system they enable a failsafe mechanism. • Similar as a human resets a non-responsive machine, the Watchdog timer automatically 'resets' the Microcontroller to a normal state when it doesn't respond normally for a specified time

14. Systems on a Chip (SOC) • Microcontrollers, while they are mini computers still require supporting circuits. • Examples: Decoders, signal converts, or signal processors • SOC incorporates all these suporting circuits and a Microcontroller in one easy and compact chip. • They are fast, small, and compact. They even consume less memory than having all the other chips that they replace

16. Embedded Software • Software written for an embedded machine needs to have the specs of the machine in mind. • The software is built in the Embedded System itself • Software also can not be fine tuned after the program is embedded onto the circuit • Need to get it right the first time!

17. Embedded Systems Memory • The Embedded System does not use virtual memory, since it relies on being quick. • Embedded programmers have to be aware of the size of memory, since it is limited based on the machine

18. The End