Microchip's PIC Micro Controller - Presentation Covers- Embedded system,Application, Harvard and Von Newman Architecture, PIC Microcontroller Instruction Set, PIC assembly language programming, PIC Basic circuit design and its programming etc.

1. Microchip®®
PIC Microcontrollers
By
Midhu S.V. Unnithan

2. Embedded Systems
What is Embedded System?
Embedded System is a combination of
software and hardware designed to perform a
specific task.
E.g. Washing Machine
Traffic Signal
Microwave Oven etc…

3. Application Areas Of Embedded
System
• Electronics Applications and Consumer Devices.
• Industrial Automation and Process Control.
• Access Control Systems.
• Security Systems.
• Robotics.
• Communications Applications.
• Automotive and Avionics Systems.
• Military and Aerospace Applications.
• Bio Medical Applications etc….

4. Processing Parts Of Embedded
System
1: Microprocessor (μp)
• Microprocessor is the Central Processing Unit.
• Microprocessor is, just simply, the processor .
• To make it to work it will need lots of external parts called
peripherals. I.e. Microprocessor don’t have inbuilt peripherals.
• Micro processor needs many external circuits to make it work. So
Microprocessor based system is called System On Board (SOB )

5. Processing Parts Of Embedded
System cont…
2: Microcontroller (μc )
• Microcontroller is the processing part in which all the essential
peripherals are integrated in a single chip
• Microcontroller = Microprocessor + Peripherals
• It can process as well as control.
• It includes all the necessary parts in one IC. So microcontroller
based system is called System On Chip (SOC)

6. Microcontroller Manufactures

7. Microchip’s PIC
• The name PIC referred to
"Peripheral Interface Controller"
• PIC is a family of Harvard Architecture microcontrollers
made by Microchip Technology.
Microchip Technology is an American manufacturer
of microcontroller, memory and analog semiconductors. The company
was founded in 1987.
For more details log on to www.microchip.com
• PICs are popular with developers and hobbyists alike.

8. Why PIC
• All the Peripherals are Integrated in a Single Chip
• Wide Range Available
• Cost Effective
• Easily Available
• High Speed
• High Performance RISC CPU
• Instruction Set Simplicity
• Wide Operating Voltage Range: 2.5 – 6 V
• Programmable Code Protection Mode
• Power Saving Sleep Mode

9. Device Structure - PIC
• Core
The essential part of the system.
• Peripherals
Peripherals are the features that add a differentiation from
microprocessors. This is the interfacing units to external world.
• Special features
Major purpose of special features are
► Decrease system cost.
► Increase system reliability.
► Increase design flexibility.

10. The PIC Family
• Based on Instruction Word Length PIC can be
classified into three.
Instruction Word Length = OPCODE+OPERAND
• Base Line (12 bit with 33 Instructions)
• Mid Range (14 bit with 35 Instructions)
• High End (16 bit with 58 / 77 Instructions)

11. Architectures …
1:Von Neumann Architecture
CPUCPU
Program Memory
&
Data Memory
• Used in: 80X86, 8051 etc…
• Only one bus between CPU and memory.
• Data memory and Program memory share the same bus
and the same memory, and so must have the same bit
width.
• Time of execution high.
8

12. Architectures …
2:Harvard Architecture
PICs use the Harvard Architecture
CPU
12
14
16
Data
Memory 8
Program
Memory
Used mostly in RISC CPUs.
Separate program bus and data bus: can be different widths.
Instructions can execute in a single cycle.
Time of execution is low.

13. Name the PIC
• Microchips Microcontroller name always Starts with PIC
• Then a Number which denotes the Type/Range of that PIC
• 12 : Base Line (12 bit Instruction Word)
• 16 : Mid Range (14 bit Instruction Word)
• 17/18 : High End (16 bit Instruction Word)
• Next is an Alphabet which denotes How We Can Program the PIC
• CR : PROM (OTP)
• C : PROM / EPROM
• F : FLASH
• Last is another Number varies from PIC to PIC which denotes the
internal memory, pin numbers, peripherals etc …
• 73 : 28 pin IC, 8 bit ADC, 4K PM etc…
• 873 : 28 pin IC, 10 bit ADC, 4K PM etc…
• 877 : 40pin IC, 10 bit ADC , 8K PM etc…
• 877 A : 40pin IC, 10 bit ADC , 8K PM, New Batch IC etc…

14. Name Yourself …….You can 
• PIC16F73 : 
• PIC16F873A : 
• PIC16F877 : 
• PIC16F877A : 

15. Instruction Set - PIC
• Only 35 instructions.
• RISC instruction architecture.
• In PIC, Accumulator is named as Working Register (w).
This is the base register of all operations.
• All operations are possible only through ‘w’
• Register to register transfer is not possible.
• The instruction set is highly orthogonal and is grouped
into three basic categories:
• Byte oriented instructions (18 nos).
• Bit oriented instructions (4 nos).
• Literal and control instructions (13 nos).

16. Instruction Set - PIC
1. Byte oriented instructions: (18 nos)
• CLRW - Clear working register.
• CLRF - Clear file register
• MOVFW - Move the contents of file register to working register.
• MOVWF - Move the contents of working register to file register.
• ADDWF - Add the contents of file register to working register.
• SUBWF - Subtract working register from the file register.
• ANDWF - Bit wise multiplication of working register with the file register.
• IORWF - Bit wise adding of working register with the file register.
• XORWF - Exclusive OR the contents of working register with the file reg:
• RLF - Rotate left with carry.
• RRF - Rotate right with carry.
• DECF - Decrement the file registers contents.
• DECFSZ - Decrement the contents of file register and skip the next
instruction if zero.
• INCF - Increment the file registers contents.
• INCFSZ - Increment the contents of file register and skip the next
instruction if zero.
• COMF - 1’s complement.
• SWAPF - Interchange the nibbles.
• NOP - No operation.

17. Instruction Set - PIC
2. Bit Oriented instructions: (4 nos)
• BCF - Bit clear flag.
• BSF - Bit set flag.
• BTFSC - Bit test file register and skip if clear.
• BTFSS - Bit test file register and skip if set.

18. Instruction Set - PIC
3. Literal and control instructions: (13 nos)
• MOVLW - Direct loading of working register.
• ADDLW - Direct adding of working register with a constant value.
• SUBLW - Direct subtraction of working register with a constant value.
• ANDLW - Bit wise multiplication of working register with a constant
value.
• IORLW - Bit wise addition of working register with a constant value.
• XORLW - Exclusive OR of working register with a constant value.
• CALL XX - Call subroutine XX.
• RETURN - Back to main program from the subroutine.
• GOTO XX - Go to xx.
• RETFIE - Return from interrupts.
• RETLW - Return with literal value.
• CLRWDT - Clear watchdog timer.
• SLEEP - Low power consumption mode.

19. Program Format
LIST P=PIC16F73 ;Listing the microcontroller
#INCLUDE“P16F73.INC” ;INC file
CBLOCK 0X20 ;GPR address starts from 0X20
•
• ;GPR Initialization
•
ENDC
ORG 0 ;Reset Vector
•
•
program
•
•
•
END ;Program End

20. Our First Program … 
• Add the contents of two registers (R1 & R2) and store the result in
R3
LIST P=PIC16F73
#INCLUDE“P16F73.INC”
CBLOCK 0X20
R1
R2
R3
END C
ORG 0
MOVLW 0X02
MOVWF R1
MOVLW 0X03
MOVWF R2
ADDWF R1,0
MOVWF R3
END

21. Do it yourself …
• Subtract the contents of M1 from M2 and store
the result in Y1
• Multiply the contents of X1 with X2 and store
the result in X3.

22. Its time to relax ….. Have a break…


23. MPLAB IDE …An Introduction
• MPLAB IDE is a software program that runs on a PC, to
develop applications for Microchip microcontrollers. It is
called an Integrated Development Environment, or IDE,
because it provides a single integrated “environment” to
develop code for PIC microcontrollers.
• You can download this software free of cost from
Microchip’s website. (www.microchip.com)

24. Most Commonly Used SFR s …
• STATUS
• OPTION_REG
• PORTA,B,C…. & TRIS A,B,C…
• ADCON0,ADCON1,ADRES
• TXSTA,RCSTA,TXREG,RCREG,SPBRG
• INTCON etc………..

25. That’s all with the software….
Lets have some Circuit Thoughts

26. Pinout Diagram – 28 pin

27. Pinout Diagram – 40 pin

28. Basic Circuit Requirements of PIC
1: Power Supply
VDD = 5V
VSS = GND

29. Basic Circuit Requirements of PIC
2: Connect Oscillator (XTAL 4 or 20 MHz) to CLKI and
CLKO pins
Also connect two 22/33 pf capacitors with the crystal as
shown below for crystal stabilization.

30. Basic Circuit Requirements of PIC
3: Pull up MCLR pin with a 10k resistance to avoid
master reset.

31. Here is your PIC basic circuit

32. SOFTWARE is ready…. 
HARDWARE is ready…. 
Its Time To Know How To Fuse The Program in PIC

33. Programmers…
• Parallel Programmers
• Serial Programmers
• USB Programmers

34. How To Program The PIC

35. Brief Project Lifecycle
• Requirement Study
• Initial Planning
• Prototype development
 May again go to Requirement study
• Final Project Planning
 Deadlines, Team/Recourses, Methods, Budget
• Development
 Hardware and Software
• Testing and Debugging
 May again go to Development
• Documentation
• Project Delivery

37. Feedbacks and Suggestions
Please…..

38. We can't solve problems by using the same kind of
thinking we used when we created them. So Think
Different (Albert Einstein)
I wish you all a very successful future….Take care
svmidhu@gmail.com