Tuesday, January 28, 2014
8 bit lcd library function for hitech-c
8 bit lcd library function for hitech-c
#ifndef D0
#define D0 RB0
#define D1 RB1
#define D2 RB2
#define D3 RB3
#endif
void Lcd8_Port(char a)
{
if(a & 1)
D0 = 1;
else
D0 = 0;
if(a & 2)
D1 = 1;
else
D1 = 0;
if(a & 4)
D2 = 1;
else
D2 = 0;
if(a & 8)
D3 = 1;
else
D3 = 0;
if(a & 16)
D4 = 1;
else
D4 = 0;
if(a & 32)
D5 = 1;
else
D5 = 0;
if(a & 64)
D6 = 1;
else
D6 = 0;
if(a & 128)
D7 = 1;
else
D7 = 0;
}
void Lcd8_Cmd(char a)
{
RS = 0;
RW= 0; // => RS = 0
Lcd8_Port(a); //Data transfer
EN = 1; // => E = 1
__delay_ms(5);
EN = 0; // => E = 0
}
Lcd8_Clear()
{
Lcd8_Cmd(1);
}
void Lcd8_Set_Cursor(char a, char b)
{
if(a == 1)
Lcd8_Cmd(0x80 + b);
else if(a == 2)
Lcd8_Cmd(0xC0 + b);
}
void Lcd8_Init()
{
Lcd8_Port(0x00);
RS = 0;
RW=0;
__delay_ms(25);
Lcd8_Cmd(0x30);
__delay_ms(5);
Lcd8_Cmd(0x30);
__delay_ms(15);
Lcd8_Cmd(0x30);
Lcd8_Cmd(0x38); //function set
Lcd8_Cmd(0x0C); //display on,cursor off,blink off
Lcd8_Cmd(0x01); //clear display
Lcd8_Cmd(0x06); //entry mode, set increment
}
void Lcd8_Write_Char(char a)
{
RS = 1; // => RS = 1
RW=0;
Lcd8_Port(a); //Data transfer
EN = 1; // => E = 1
__delay_ms(4);
EN = 0; // => E = 04
}
void Lcd8_Write_String(char *a)
{
int i;
for(i=0;a[i]!='\0';i++)
Lcd8_Write_Char(a[i]);
}
void Lcd8_Shift_Right()
{
Lcd8_Cmd(0x1C);
}
void Lcd8_Shift_Left()
{
Lcd8_Cmd(0x18);
}
EXTERNALINTERRUPT(PIC16F877A)-programming
PROGRAM
#include<pic.h>
#include<htc.h>
#define RS RC0
#define RW RC1
#define EN RC2
#define D0 RD0
#define D1 RD1
#define D2 RD2
#define D3 RD3
#define D4 RD4
#define D5 RD5
#define D6 RD6
#define D7 RD7
#define _XTAL_FREQ 4000000
__CONFIG(WDTDIS & XT & UNPROTECT);
#include"lcd.h"
char a[10];
int count=0,i;
void interrupt isr()
{
if(INTF==1)
{
count++;
i=count;
a[1]=i%10+0x30;
i=i/10;
a[2]=i%10+0x30;
if(count<10)
{
Lcd8_Clear();
Lcd8_Set_Cursor(1,0);
Lcd8_Write_Char(a[1]);
}
if(count>9)
{
Lcd8_Clear();
Lcd8_Set_Cursor(1,0);
Lcd8_Write_Char(a[2]);
Lcd8_Set_Cursor(1,1);
Lcd8_Write_Char(a[1]);
}
INTF=0;
}
}
void main()
{
TXSTA=0X24;
RCSTA=0X90;
SPBRG=0X19;
TRISC=0x80;
TRISD=0x00;
TRISB=0x01;
TXIF=0;
RCIF=0;
GIE=1;
PEIE=1;
RCIE=1;
INTE=1;
INTEDG=1;
INTF=0;
Lcd8_Init();
Lcd8_Clear();
Lcd8_Set_Cursor(1,0);
Lcd8_Write_String("interrupt");
while(1);
}
EXTERNAL INTERRUPT CONFIGURATION IN PIC16F877A
EXTERNAL INTERRUPT CONFIGURATION IN PIC16F877A
- External interrupt pin of pic16f877a is RB0.
- for setting external interrupt first set TRISB=0x00;(as output)
- Then GIE=1,PEIE=1 and INTE=1
- Then write interrupt service routine
- When interrupt happen the flag INTF will set.
- Then clear the flag in interrupt routine itself for next interrupt
- sample code is given below.
#include<pic.h>
int i;
void interrupt isr()
{
if(INTF==1)
{
i++;
INTF=0;
}
}
void main()
{
TRISB=0x00;
GIE=1;
PEIE=1;
INTE=1;
while(1);
}
This is the program for external interrupt in pic 16f877a micro controller
Friday, January 24, 2014
PIC16F877A basic tutorial
PIC16F877A
PIN
DIAGRAMS
I/O PORTS DIRECTION CONTROL REG. NO OF PINS
PORTA TRISA 6
PORTB TRISB 8
PORTC TRISC 8
PORTD TRISD 8
PORTE TRISE 3
EXAMPLE:
TRISB=0XFF MAKE PORTB AS INPUT PORT
TRISB=0X00 MAKE
PORTB AS OUTPUT PORT
BASIC PROGRAM TO ON/OFF LED’S
#include<pic.h>
void delay()
{
int i;
for(i=0;i<10000;i++);
}
void main()
{
TRISA=0X00; // MAKE PORTA AS OUTPUT//
while(1)
{
PORTA=0XFF; //LED’S - ON//
delay();
PORTA=0X00; //LED’S-OFF//
delay();
}
}
UNIVERSAL
SYNCHRONOUS ASYNCHRONOUS RECEIVER TRANSMITTER (USART)
SPBRG=X
BAUD
RATE =FOSC / (16(X+1))
BASIC
PGM FOR TRANSMISSION
#
include<pic.h>
#define
_XTAL_FREQ 4000000
__CONFIG(WDTDIS
& XT & UNPROTECT);
void
main()
{
TXSTA=0X24;
RCSTA=0X90;
SPBRG=0X19;
TRISC=0X80;
while(1)
{
TXREG='k';
while(TXIF==0);
TXIF=0;
}
}
LCD
INTERFACING PROGRAM
#include<pic.h>
#define
_XTAL_FREQ 4000000
__CONFIG(WDTDIS
& XT & UNPROTECT);
void
delay()
{
int
i;
for(i=0;i<10;i++);
}
void
COMMAND(char t)
{
PORTD=t;
RC0=0;
RC1=0;
RC2=1;
delay();
RC2=0;
}
void
data(char t)
{
PORTD=t;
RC0=1;
RC1=0;
RC2=1;
delay();
RC2=0;
}
void
main()
{
TRISC=0X00;
TRISD=0X00;
COMMAND(0X06);
COMMAND(0X0E);
COMMAND(0X01);
COMMAND(0X80);
COMMAND(0X38);
while(1)
{
data('w');
delay();
}
}
Basic Circuit Of PIC16F877A
Basic Circuit Of PIC16F877A
Power
Supply
To
start up your PIC16F877A, there are 7 pins you should connect correctly. Likes
others electronic component, the supply pin is the most important. The ideal
voltage for PIC16F877A is 5V (Direct Current). It should not be higher then
5.5V because it going to blow up. It also should not be less then 2V because it
not going to be operate. You will have various type of supply such as battery
and DC adapter. The problem is, if you use battery, it hard to fine normal
battery in 5V. Yes you can use 3 normal 1.5V battery that connected in series.
But I don’t think it will be efficient enough. So how if I use 9V battery? Yes
I can use it but I need to step it down to 5V. How? You can use voltage
regulator. LM7805 the part number of the voltage regulator that I used. The two
number at the end of the part number is 05 which is mean it will step down the
larger input voltage to 5V. Let say if use LM7809 it will step down the higher
voltage then 9V to 9V. Here is the datasheet. This is the basic
connection to step down 9V to 5V by using LM7805.
Using
LM7805 is not only limited to battery supply source. But you can also use it at
your rectifier circuit. Picture below show how the connection from the output
of rectifier to the LM7805 and to PIC16F877.
Reset
Pin
So,
how to give power supply to PIC is already covered. As I said before, there are
7 pins should be connect in order to let your PIC operate. 4 pins is already
connected which is 2 pins for 5V and 2 pin for ground (negative). It 3 more
pins left. The other important pin is Reset pin (MCLR - Master Clear Reset at
Pin number 1). If PIC read 0V at MCLR pin, it will reset the program, so if you
not connect the MCLR pin with 5V, PIC will remain reset and your program will
not execute. You can directly connect the MCLR with 5V (series with resistor
likes picture below) but you will unable to reset if your system goes wrong.
If
you want to use the reset function, you need to create logic condition which is
1 and 0 to the reset pin. 1 is mean the reset pin get 5V. If the reset pin
logic is 1, then the program in your PIC will execute, but if the reset pin
logic condition is 0 (which is 0V) then your PIC will not execute the program.
Logic Condition
|
Voltage
|
Program Status
|
0
|
0V
|
Not Execute
|
1
|
5V
|
Execute
|
So,
how you can get this condition? The answer is simple, you just need a switch.
But you cannot simply add a switch between the 5V and the reset pin. You will
need the Pull Up Resistor. What is that thing? See the picture below, that is
the correct way how to add up a switch in order to create the logic condition.
When
the switch is not pushed, current will flow trough 10K resistor and MCLR Pin.
As a result, MCLR Pin receive 5V and PIC read it as logic 1. But when switch is
push, current will flow through 10K resistor, switch and directly to ground.
There is no voltage will receive at MCLR Pin. This give 0 logic at MCLR Pin.
The
Oscillator
Five
from seven of important pins already covered, now there are only 2 pin left
which is pin number 13 and 14. Those pin was named as OSC1 and OSC2. You can
connect the crystal osillator from various frequency. Pulse generated from the
oscillator will some time have the noise. To reduce the noise, two capacitors
in piko farad value is needed. The value of capacitor is depend on the speed of
oscillator that you use. Here is the way how to connect the the crstal
oscillator and capacitor value table.
VCC (+5V)
|
GND
|
PIN 11
|
PIN 12
|
PIN 32
|
PIN 31
|
SAMPLE TRANSMISSION PROGRAM FOR PIC16F877A
SAMPLE TRANSMISSION PROGRAM FOR PIC16F877A
# include<pic.h>
#define _XTAL_FREQ 4000000
__CONFIG(WDTDIS & XT & UNPROTECT);
void main()
{
TXSTA=0X24;
RCSTA=0X90;
SPBRG=0X19;
TRISC=0X80;
while(1)
{
TXREG='k';
while(TXIF==0);
TXIF=0;
}
}
This is a sample program for transmitting character 'k' continuously.
# include<pic.h>
#define _XTAL_FREQ 4000000
__CONFIG(WDTDIS & XT & UNPROTECT);
void main()
{
TXSTA=0X24;
RCSTA=0X90;
SPBRG=0X19;
TRISC=0X80;
while(1)
{
TXREG='k';
while(TXIF==0);
TXIF=0;
}
}
This is a sample program for transmitting character 'k' continuously.
Wednesday, January 22, 2014
DISASTER MANAGEMENT ROBOT PROJECT FOR FINAL YEAR ECE STUDENTS
For more details contact me...........................
Tuesday, January 21, 2014
SERIAL COMMUNICATION FOR PROTEUS
To do serial communication through putty or terminal software for proteus just follow the below steps.
1.
Then use a software named as VPSE
1.
Use COMPIM in devices->miscellaneous as DB9
In COMPIM edit properties as follow
Configure VPSE as follows
1.
Select device in toolbar. Select device type as connector. Then click next.
2.
Select the desired com port . Then tick emulate baud rate. Press finish.
3.
Now press the play button. Thats all now you can do the serial communication using terminal or putty for proteus.
THANKS,
PUTTY - faster serial communication software
.http://www.downloadputty.net/
Putty is a faster serial communication software . For configuration check the previous post
TERMINAL SOFTWARE FOR SERIAL COMMUNICATION
Use terminal software for view serial communication between PC and micro controllers.
-> Select port for your serial cable
-> Set baud rate as 9600
-> Bit used is 8
-> Parity as none
-> Stop bit as 1
-> Handshaking as none
Plug your serial cable and play......................................
MPLAB programming for PIC
From project select project wizard.
Click next and select the device that you want.Here i am using pic16f877a.
Click next . Then select Hitech-c compiler.
Then select next and name your project by browsing.
Then click next.
Next.
Then click finish.
After finish you will get this window . Then create a new file .
Then save the new file with an extension *.c
If your program is correct you will get this winow
Thank you,
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