Embedded Systems Flashcards
What are embedded systems?
An embedded system is a combination of software and hardware that performs a specific task rather than a general-purpose computer that is designed to carry out multiple tasks.
How do embedded systems work?
The software written for an embedded system is called firmware. The instructions are stored in read-only memory or in Flash memory. The software runs with limited computer hardware resources, little memory and no peripherals.
Reactive embedded systems?
Most embedded systems are reactive – they react to conditions such as temperature, weight, vibration and air quality. These systems detect external conditions and react to them by recording data, turning motors on or off, sounding an alarm or sending a message to another processor.
Reactive embedded systems often control real time events so must be completely reliable. For example, drivers rely of the anti-lock braking system of their car working correctly to avoid accidents on the road.
How reliable?
When an embedded system performs operations at high speed, and if it is very reliable, it can be used for real-time applications. If the size of the embedded system is very small and power consumption is very low, the system can be easily adapted for different situations.
Some examples of embedded systems
Electronics
Mobile phones, games consoles, printers, televisions, digital cameras.
In the home
Washing machines, microwave ovens, refrigerators, dishwashers, air conditioners.
Medical equipment
CT scanners, electrocardiograms (ECG), MRI scanners, blood pressure monitors, heartbeat monitors.
Cars
Electronic fuel injection systems, anti-lock braking systems, air-conditioner controls.
