A PIC microcontroller adds sophisticated digital control capabilities when connected to other circuits and devices. A single PIC microcontroller can communicate with other electronic devices, and digitally switch them on or off to control simple operations.

Microchip Technology, Inc. produces a family of PIC processors capable of storing programs. The PIC16F84A, which we will use in this lab, contains electrically erasable programmable ROM (EEPROM), which is memory used to store programs. The program in EEPROM can be overwritten many times during the design cycle.

The PIC has 64 bytes of data EEPROM and 1792 bytes of program EEPROM for storing compiled programs. It operates at 4 or 10 MHz depending upon an external crystal oscillator. The 18 pin PIC has 13 pins capable of operating as either inputs or outputs, designated by software that can be changed during program execution.

Five of the pins are grouped together and referenced as PORTA; another 8 pins are group together and referenced as PORTB.

• Introduction
• PIC structure