3. Enhanced Mid-Range PIC
These controllers are enhanced version of Mid-Range core. This range of controllers provides additional performance, greater flash memory and high speed at very low power consumption. This range of PIC also includes multiple peripherals and supports protocols like USART, SPI, I2C and so on.
PIC18 range is based on 16-bit instruction architecture incorporating advanced RISC architecture which makes it highest performer among the all 8-bit PIC families. The PIC18 range is integrated with new age communication protocols like USB, CAN, LIN, Ethernet (TCP/IP protocol) to communicate with local and/or internet based networks. This range also supports the connectivity of Human Interface Devices like touch panels etc.
The following table compares the above four categories:
No. of Pins
Up to 3 KB
Up to 14 KB
Up to 28 KB
Up to 128 KB
Up to 134 Bytes
Up to 368 Bytes
Up to 1.5 KB
Up to 4 KB
No. of instruction set
Up to 16 MIPS
• 8-bit ADC
• Data Memory
In addition of baseline
· 10-bit ADC
In addition of Mid-range
· High Performance
· Multiple communication peripherals
In addition of Enhanced Mid-range
• 12-bit ADC
*MIPS stand for Millions of Instructions per Second
Besides 8-bit microcontrollers, Microchip also manufactures 16-bit and 32-bit microcontrollers. Recently Microchip developed XLP (Extreme Low Power) series microcontrollers which are based on NanoWatt technology. These controllers draw current in order of nanoamperes(nA).
The PIC microcontrollers are available with different memory options which are mask ROM, EPROM and flash memory. They are denoted with different symbols as given in the following table:
PIC microcontrollers are also available with extended voltage ranges which reduce the frequency range. The operating voltage range of these PICs is 2.0-6.0 volts. The letter ‘L’ is included in controller’s name to denote extended voltage range controllers. For example, PIC16LFxxx (Operating voltage 2.0-6.0 volts).
The following section covers the PIC architecture in further detail. PIC18 series has been selected for the study because it is enhanced series of 8-bit PIC microcontroller. In this series, PIC18F4550 has been chosen to describe the architecture and other features due its moderate complexity.