What is Microcontroller?
Microcontroller can be categorized as a computer. It embedded common computer components into a single chips such as:
- A CPU (Central Computing Unit) core
- Memory (both ROM and RAM)
- input output (I/O) interface such a parallel or serials ports
- peripherals such as timers and watchdog.
- clock generator (may be is oscillator for a quartz timing crystal, resonator or RC circuit)
The following diagram show block diagram for a simple microcontroller :
Microcontroller is different from microprocessor because microprocessor only contain a CPU core and memory interface for user to connect its own external chips for the memory, I/O and even the peripheral. The born of microcontroller have drastically reduces the number of chips need to use. Therefore help to reduce the amount of wiring and PCB space that would be needed to produce equivalent systems using separate chips. So by embedded almost all needed devices in a single chips, the cost to build a system is greatly reduce. Another great feature is low power, a battery-operated microcontroller might only consume as low as 50 milliwatts or lower.
CPU of microcontroller can be variant from 4-bit to 32-bit and even 64-bit, this depend on what type of microcontroller need to produce. 8-bit microcontrollers are the most popular among other, such as MCS-51, PIC, AVR and more. Some will use a DSP core, such as dsPIC. EPROM, EEPROM or Flash memory is usually integrate as its ROM to store the program, the size can be as small as 1KBytes or as big as few 20KBytes. RAM in microcontroller is usually used as data storage and variant from 20 Bytes to few 1KBytes. Some microcontroller even have integrate a ADC ( Analog to Digital converter), PWM (Pulse Width Modultion), SPI inteface or USB interface into a single chips.
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