Invention of 8051 micro-controller had proved to be a revolutionary step in the history of embedded system. Being inspired from 8051, various IC manufacturers initiated the development of other architecture with more features and easy interface on chip. New age micro-controllers aims to have varieties of features such as ADC, DAC, RTC, Comparators, Timers and latest communication protocols like UART, I2C, SPI, USB, Ethernet etc. on chip which helps the developers to design system which is compact and power efficient. AVR from Atmel, PIC from Microchip, ARM family, Cortex Series etc. are the major families leading the race.
In this tutorial, we will learn about history along with various families of PIC Controllers.
16 bit CPU CP1600 (childhood version of PIC controller family) was born in 1975 at Micro-electronics Division of General Instruments. Although CP1600 had great set of features, it was having an issue of low I/O performance. The PIC controller was used to offload I/O task from CP1600 which showed significant improvement in overall performance of CP1600.
In 1985, Micro-electronics Division was converted to Microchip Technology. They keep on improving the performance and combined CP1600 with PIC. In 1993, enhanced version of PIC (which had inbuilt EEPROM and bootloader to program the IC using UART) was launched which was named as PIC16C84. Improved version of this with flash memory came in to market in 1998.
Since 1998, Microchip has shown significant growth in development and has produced various micro-controllers with wide range of varieties in features, memory, package and I/O capacity. Undoubtedly, PIC has achieved a remarkable share as IC manufacturing.
Families of PIC
Microchip has developed different families of PIC each having various micro-controllers to match with your requirement. PIC controllers are having Harvard architecture at its heart. Base line and mid-range controllers have 8 bit architecture where enhanced mid-range and PIC18 series has 16 bit wide memory. Microchip has come up with latest PIC32MZ having 32 bit memory also.
Low range (Base Line)
The first family from Microchip is PIC10 series. It has RISC architecture with 33 single word machine cycle or instructions. It has 8 bit ALU and register set for easy operation. Features such as low-cost devices, high-performance, fully static operation, flash based CMOS controllers etc. attracts the beginners a lot. 12 bit wide easy to use, easy to remember helps to reduce development time drastically. What else does a beginner need?
Mid-range ICs of PIC Controller has 14 bit instruction architecture with additional topping of ADC, PWM, Op-Amps, communication protocols such as USART, I2C, SPI etc. which makes it more suitable for industrial applications. These controllers has wide range of package to match with your requirements.
These controllers are enhanced version of mid-range series. These controllers has more memory with high speed operation along with power management modes. These features make them more suitable for higher end industrial applications.
Among all the 8 bit series, these family yields you the highest performance which is based on 16 bit instruction architecture. It comes with advanced communication protocols such as USB, Ethernet, CAN etc. These protocols are widely used to communicate with other devices in local network as well as servers. Most interestingly, these family also has wide range of HID (Human Interface Devices) such as USB Keyboard, Mouse, Touch panels etc. It’s interesting to have everything on a single chip. Isn’t it?
Microchip is never satisfied with their work and that’s what keeps them encouraged to invent something better. They have come up with enhanced version of PIC Family named as PIC32. These microcontrollers has wide range of varieties in terms of memory, on chip features, peripheral performance, power consumption utilization, communication protocols etc. These are most suitable for higher end consumer electronics product development.
Apart from the features, PIC controller also has different type of memory. Type of memory is indicated by a specific letter.
Before continuing further, we shall take an overview on comparison of above families.
|Base Line||Mid-Range||Enhanced Mid-Range||PIC18|
|Pins of controller||6-40||8-64||8-64||18-100|
|Data memory||Up to 134 bytes||Up to 368 bytes||Up to 1.5 kB||Up to 4 kb|
|Program memory||Up to 3 kb||Up to 14 kb||Up to 28 kb||Up to 128 kb|
|Instruction length||12 bit||14 bit||14 bit||16 bit|
|No. of instructions available||33||35||49||83|
|Execution Speed (MIPS)||5||5||8||Up to 16|
|In addition of base line
|In addition of Mid-range
Multiple communication peripheral
|In addition of enhanced mid-range
12 bit ADC
We will study more about PIC controllers in next tutorial.