The PICmicro was originally designed around 1980 by General Instrument as a small, fast, inexpensive embedded microcontroller with strong I/O capabilities. PIC stands for "Peripheral Interface Controller". General Instrument recognized the potential for the little PIC and eventually spun off Microchip, headquartered in Chandler, AZ to fabricate and market the PICmicro.
The PICmicro has some advantages in many applications over the older chips such as the Intel 8048/8051/8052 and its derivatives, the Motorola MC6805/6hHC11, and many others. Its unusual architecture is ideally suited for embedded control. Nearly all instructions execute in the same number of clock cycles, which makes timing control much easier. The PICmicro is a RISC (Reduced Instruction Set Computer) design, with only thirty-odd instructions to remember; its code is extremely efficient, allowing the PIC to run with typically less program memory than its larger competitors.
Very important, though, is the low cost, high available clock speeds, small size, and incredible ease of use of the tiny PIC. For timing-insensitive designs, the oscillator can consist of a cheap RC network. Clock speeds can range from low speed to 20MHz. Versions of the various PICmicro families are available that are equipped with various combinations ROM, EPROM, OTP (One-Time Programmable) EPROM, EEPROM, and FLASH program and data memory. An 18-pin PICmicro typically devotes 13 of those pins to I/O, giving the designer two full 8-bit I/O ports and an interrupt. In many cases, designing with a PICmicro is much simpler and more efficient than using an older, larger embedded microprocessor.
SOURCE FROM: botkin.org
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