A microcontroller can be considered a self-contained system with a processor, memory and peripherals and can be used as an embedded system. The majority of microcontrollers in use today are embedded in other machinery, such as automobiles, telephones, appliances, and peripherals for computer systems.
Microcontrollers usually contain from several to dozens of general purpose input/output pins (GPIO). GPIO pins are software configurable to either an input or an output state. When GPIO pins are configured to an input state, they are often used to read sensors or external signals.
Typical input and output devices include switches, relays, solenoids, LED’s, small or custom liquid-crystal displays, radio frequency devices, and sensors for data such as temperature, humidity, light level etc.
A micro-controller is a single integrated circuit, commonly with the following features:
- Central processing unit
- Volatile memory (RAM) for data storage
- ROM for operating parameter storage
- Serial input/output such as serial ports (UARTs)
- Peripherals such as timers, event counters, PWM generators
- Clock generator
- many include analog-to-digital converters, some include digital-to-analog converters
Some of the microcontrollers to be discussed are given below,