Real-time system
respond to some external stimuli within a stated/minimum time. For example, an alarm will sound immediately (or a light will switch on) when a PIR sensor detects movement.
Embedded Systems
a combination of hardware and software designed to
perform a specific function. They are called ‘embedded’ because they are often used as part of a larger system. Many embedded systems use sensors to receive analogue or digital inputs
Advantages of Embedded Systems (ES)
-Generally cheaper
-fast (typically run on a dedicated micro-controller)
-more reliable since they’re less complex
-automated (requires minimal user intervention once started)
-portability(generally smaller size)
Examples of Embedded Systems
Can be part of devices and larger systems
-Camera
-GPS
-Washing Machine
-Microphone
-ATM
-Drone
-Central heating
-fire alarm
-mp3 players
-microbit
-Voice control devices (Alexa)
What differentiates embedded systems from general systems
- Designed for specific tasks. Unlike computer systems they cannot be programmed to do anything beyond what they were designed for.
- Minimal user interface and easy to use
- little to no human intervention required
- Use microprocessors or microcontrollers to design and use limited memory
- Typically don’t require much power
Disadvantages of Embedded Systems
- Limited power and memory restricts functionality
- Can’t adapt to new tasks or requirements
- Vulnerable to security attacks due to specialized hardware
- ES connected to a network can be vulnerable to attack if network is attacked. e.g. malware and batabreaches
