Features of PIC Microcontroller

PIC microcontrollers are amazingly powerful fully featured processor with internal RAM, EEROM FLASH memory and peripherals. One of the smallest ones occupies the space of a 555 timer but has a 10bit ADC, 1k of memory, 2 timers, high current I/O ports a comparator a watch-dog timer.

PIC microcontrollers are available depending upon specifications:

Memory Type	Flash OTP (One-time-programmable) ROM (Read-only-memory) ROMless
I/O Pin Count	4–18 pins 20–28 pins 32–44 pins 45 and above pins
Memory Size	0.5–1K 2–4K 8–16K 24–32K 48–64K 96–128K
Special Features	CAN USB LCD Motor Control Radio Frequency

Although there are many models of PIC microcontrollers, the nice thing is that they are upward compatible with each other. A program developed for one model can very easily, and in many cases without modifications, can be run on other models of the family.

The basic assembler instruction set of PIC microcontrollers consists of only 33 instructions and most of the family members (except the newly developed devices) use the same instruction set. This is why a program developed for one model can run on another model with similar architecture without any changes.

Basic features of PIC microcontrollers:

● Harvard RISC instruction set
● Digital I/O ports
● On-chip timer with 8-bit prescaler
● Power-on reset
● Watchdog timer
● Power saving SLEEP mode
● High source and sink current
● Direct, indirect, and relative addressing modes
● External clock interface
● RAM data memory
● EPROM or Flash program memory

Additional features:

● ADC/DAC
● Comparators
● Advanced Timer
● EEPROM
● External and Internal interrupts
● Internal Oscillator
● PWM
● USART

Advanced features:

● CAN bus interface
● I2C bus interface
● SPI bus interface
● Direct LCD interface
● USB interface
● Motor control

Selection of PIC Microcontroller

There are many PIC models, which can fulfill your Embedded System requirements. While selecting the PIC or any microcontroller for Embedded System, the microcontroller should satisfies the minimum requirements and the does not offer more than the system requirement.

Few factors to be consider while selecting a Microcontroller for Embedded System Design:

● Number of I/O pins required
● Required peripherals (e.g. USART, USB)
● The minimum size of program memory
● The minimum size of RAM
● Whether or not EEPROM non-volatile data memory is required
● Speed
● Physical size
● Cost