PIC MICROCONTROLLER Features & Applications
WHAT IS A MICROCONTROLLER
• A smaller computer• On-chip RAM, ROM, I/O ports... • Example:Motorola’s 6811, Intel’s 8051, Zilog’s Z8
and PIC 16X
RAM ROM
I/OPort Timer
Serial COMPort
CPU A single chip Microcontroller
HOW IT IS DIFFERENT FROM A MICROPROCESSOR
General-purpose microprocessor• CPU for Computers• No RAM, ROM, I/O on CPU chip itself• Example: Intel’s x86, Motorola’s 680x0
CPU
General-Purpose Micro-processor
RAM ROM I/O Port
TimerSerial COM Port
Data Bus
Address Bus
Types of Microcontrollers
IMPORTANT FEATURES OF PIC 16F73
• High performance RISC CPU.• There is Only 35 single word instructions.• 4K Bytes Flash Program Memory.• 192 Bytes RAM.• Three I/O ports – PORT A = 6 Bit. PORT B & C = 8 Bit.• on-chip RC Oscillator.
PIN DESCRIPTION
PIC MEMORY
• The PIC 16F73 has 4 kbytes of program memory.
• 192 Bytes Registers as Data Memory : Special Function Registers: used to control
peripherals and PIC behaviors. General Purpose Registers: used for temporary
storage of data.
PIC PROGRAM MEMORYTakes a max of 8 addresses, the ninth address will write over the first.
When the controller is reset, program execution starts from here.
If interrupted, program execution continues from here.
PIC DATA MEMORYThe most important registers have addresses in all the four banks
The data memory is divided into 4 memory banks
PERIPHERAL FEATURES OF PIC
• Three timers –Timer0: 8-bit timer Timer1: 16-bit timer Timer2: 8-bit timer • Two PWM modules• 8-bit, 5-channel Analog-to-Digital converter.• USART And SSP Serial Communication.• Brown-out detection circuitry with Watchdog
timer.
PIC Peripherals: Timers
The PIC16F73 has 3 TimersThey can be used as- TIMER: When The clock source is the internal crystal
frequency of the PIC. COUNTER: When an external pulse is given from the
input pin. For timer0 input pin is pin number 6 i.e TOCKI For timer1 input pin is pin number 11 i.e T1CKI
Special features of timers
Only timer0 and timer1 can be used as a Timer and Counter. Timer2 is related with PWM wave generation.
Every timer is associated with pre-scaler factor. Generate interrupts on timer overflow.There is a Watchdog Timer with brown out
detection circuit.
REGISTER ASSOCIATED WITH TIMER0 OPTION_REG Register
REGISTER ASSOCIATED WITH TIMER1T1CON:Timer1 Control Register
REGISTER ASSOCIATED WITH TIMER1T1CON:Timer1 Control Register
PIC Peripherals: PWM
PWM stands for pulse width modulation. It is generally used to slow down the speed of motors by varying the duty cycle of the period.DUTY CYCLE is given by- Ton time / T total time The ratio between ON and OFF
state of the pulse determines the amount of energy tranferred to the device.
BLOCK DIAGRAM AND OUTPUT WAVEFORM OF PWM
PIC Peripherals: ADC
• ADC stands for analog to digital comparator.• In PIC16F73 there is 8 bit , 5 channels ADC.Therefore there are 256 combinations• For conversion of analog voltage to digital first
we have to make a least count matching between the two devices.
Least Count=Vref. /resolution
BLOCK DIAGRAM OF ANALOG TO DIGITAL CONVERTER
The A/D module has four registers. These registers are:A/D Result Register (ADRES)A/D Control Register0 (ADCON0)A/D Control Register1 (ADCON1)
PIC Peripherals: USART And SSP Serial Communication
USART REGISTERS
USART stands for synchronous asynchronous serial receiver and transmitter
IT DEALS WITH TWO REGISTERS:TXSTA : Transmit status and control register.RXSTA : Receive status and control register.In synchronous communication we have to give the same clock
to both the transmitter and receiver whereas In asynchronous communication we have to make the baud
rate( data transfer rate ) of both the transmitter and receiver same.
INTERFACING TO PC
SSP SERIAL COMMUNICATION
SSP stands for synchronous serial peripherals.InPIC16F73 there are 2 SSP’s-I2C AND SPII2C COMMUNICATION
SPI COMMUNICATION
APPLICATIONSINTERFACING OF LCD WITH PIC16F73
PIC16F73
PORTPINS
INTERFACING OF SEVEN SEGMENT DISPLAY WITH PIC16F73
PIC16F73
PIC16F73
Thank You For Your Attendance
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