Features of PIC18FXXX Series Microcontrollers

Features of PIC18FXXX Series Microcontrollers

• Important Features of PIC18FXXX Series Microcontrollers are:

1. Harvard architecture: PIC uses Harvard architecture. Harvard architecture has the program memory and data memory as separate memories and are accessed from separate buses. This improves bandwidth over traditional Von Neumann architecture in which program and data are fetched from the same memory using the same bus.

2. High performance RISC processors

■ C-Language friendly architecture

■ PIC16 source code compatible

■ Linear program memory addressing to 2 Mbyte

■ Linear data memory addressing up to 4 Kbytes

■ Up to 10 MIPS operation

■ 16-bit wide instructions, 8-bit wide data path

■ Priority levels for interrupts

■ 8 × 8 Single cycle hardware multiplier

3. Register file architecture: The register files/data memory can be directly or indirectly addressed. All special function registers, including the program counter, are mapped in the data memory.

4. Instruction set simplicity

■ Reduced instruction set: The instruction set of PIC consists of only 77 instructions.

■ Orthogonal (symmetric) instructions: The instructions are orthogonal. It is possible to carry out any operation on any register using any addressing mode when the instructions are orthogonal.

■ Single word instructions.

5. FLASH program memory: In sizes from 8 to 128 Kbytes

6. Data RAM: From 256 to 4 Kbytes

7. Built-in power-on-reset: PIC has a built-in power-on-reset.

8. Brown-out reset: PIC has a brown-out-reset. A brown-out-reset feature causes a reset of the PIC when the power supply voltage drops below 4 V or so.

9. Watchdog Timer (WDT): Watchdog timer is a special timer with specific function. It is used to prevent software crashes, i.e. endless loop.

10. Power saving SLEEP mode: The PIC can put itself to sleep to save power during intervals when it has nothing to do. Thus, PIC supports a power saving SLEEP mode.

11. Flexible 8 and 16-bit timers

12. Interrupt Control: The PIC can control up to 12 independent interrupt sources.

13. 10-bit ADC (Analog to digital converter)

14. Capture/Compare/PWM (CCP) modules: Up to five (CCP) modules.

15. Powerful output pin control

16. Built-in serial peripheral interface

17. EPROM/OTP/ROM Options

18. Low power consumption

Review Question

1. Explain the important features of PIC18FXXX series microcontrollers.