I/O connection:
TX and RX->UART RX and TX
Ground of Ic ->UART ground
#include<htc.h>
#define _XTAL_FREQ 20000000 //crystal frequency of 20MHZ
#include "uart.h" //header file
#include "string.h" //header file
char val;
void main()
{
__delay_ms(1000); //provide delay for 1s
UART_Init(9600); //calling initialization function with 9600 baud rate
__delay_ms(1000); //provide delay for 1s
UART_Write_Text("RDL"); //Display RDL on hyper terminal
do
{
if(UART_Data_Ready()) //check whether it is ready to receive a data
{
recieve = UART_Read(); //read a data and store in variable
UART_Write(recieve); //display on terminal
UART_Write(10); //enter
UART_Write(13); //carriage return
__delay_ms(1000); //provide delay of 1s
}while(1);
char UART_Init(const long int baudrate)
unsigned int x;
x = (_XTAL_FREQ - baudrate*64)/(baudrate*64);
if(x>255)
{
x = (_XTAL_FREQ - baudrate*16)/(baudrate*16);
BRGH = 1; //High Baud Rate Select bit set to high
}
if(x<256)
{
SPBRG = x; //Writing SPBRG register
SYNC = 0; //Selecting Asynchronous Mode
SPEN = 1; //enables serial port
TRISC7 = 1;
TRISC6 = 1;
CREN = 1; //enables continuous reception
TXEN = 1; //enables continuous transmission
return 1;
}
return 0;
}
char UART_TX_Empty()
{
return TRMT; //Returns Transmit Shift Status bit
}
char UART_Data_Ready()
{
return RCIF; //Flag bit
}
char UART_Read() //this function is used to read a byte
{
while(!RCIF); //Waits for Reception to complete
return RCREG; //Returns the 8 bit data
}
void UART_Read_Text(char *Output, unsigned int length)//this function is used to read a text
{
int i;
for(int i=0;i<length;i++)
Output[i] = UART_Read();
}
void UART_Write(char data) //this function is used to write a byte
{
while(!TRMT);
TXREG = data; //transmit register
}
void UART_Write_Text(char *text) //this function is used to write a string
{
int i;
for(i=0;text[i]!='\0';i++)
UART_Write(text[i]);
}
Lab 5.Interfacing PWM to vary the brightness of LED
I/O connection:
PORT C1->LED1
PORTC2->LED2
#include<htc.h>
#define XTAL 20000 //20Mhz=20000Khz
#define PWM_Freq 1 //1Khz PWM frequency
#define TMR2_PRE 16 //Timer2 Prescale
#define PR2_Val ((char)((XTAL/(4*TMR2_PRE*PWM_Freq))-1))
//Calculation for Period register PR2 (2Khz)
#define Duty_Cyc PR2_Val*2
unsigned int i;
void PWM_init(void); // This function is to initialize the PWM
void PWM_change(unsigned int); //This function is to change theDuty cycle routine
void DelayMs(unsigned int); //this function is to provide a delay
void main(void)
{
PWM_init();
while(1)
{
i=0;
PWM_change(i);
DelayMs(10);
while(i<PR2_Val)
{
i=i+1;
PWM_change(i);
DelayMs(200);
}
}
}
void PWM_init(void)
{
TRISC2=0; //PWM channel 1 and 2 configured as output
TRISC1=0;
PORTC = 0x00;
CCP1CON=0x0c; //CCP1 and CCP2 are configured for PWM
CCP2CON=0x0c;
PR2=PR2_Val; //Move the PR2 value
T2CON=0x03; //Timer2 Prescale is 16
TMR2=0x00;
TMR2ON=1; //Turn ON timer2
}
void PWM_change(unsigned int DTY) //Duty cycle change routine
{
CCPR1L=DTY; //Value is between 0 to 255
CCPR2L=DTY;
}
void DelayMs(unsigned int Ms) //Delay Routine
{
int delay_cnst;
while(Ms>0)
{
Ms--;
for(delay_cnst = 0;delay_cnst <220;delay_cnst++); //delay constant for 1Ms @20Mhz
}
}
I/O connection:
PORT D0 to D7->DO to D7 of LCD
ENABLE->C0
R/W->GROUND
R/S->C1
R1,R2,R3,R4->PORT B0 to B3
C1,C2,C3,C4->PORT4 to B7
#include <htc.h>
#include <stdio.h> // Define I/O functions
#define XTAL 20000000
#define BAUD_RATE 9.6 //9600 Baudrate
#define BAUD_VAL (char)(XTAL/ (16 * BAUD_RATE )) - 1;
//Calculation For9600 Baudrate @20Mhz
#define EN RC0
#define RS RC1
void ScanCol(void); //Column Scan Function
void ScanRow(void); //Row Scan Function
void DelayMs(unsigned int);
void LCD_Cmd(unsigned char);
void LCD_Init(void);
void LCD_Display( char *addr);
void LCD_SendDataByte(unsigned char);
unsigned char KeyArray[4][4]= { '1','2','3','4',
'5','6','7','8',
'9','A','B','C',
'D','E','F','0'};
//Keypad value Initialization Function
unsigned char Count[4][4]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
int Col=0,Row=0,count=0,i,j;
void main()
{
TRISD=0x00; //set registerD as output
TRISC=0x00; //set register C as output
LCD_Init(); //initialize LCD
DelayMs(1000);
nRBPU=0; //Enable PORTB Pullup values
while(1)
{
TRISB=0X0f; // Enable the 4 LSB as I/P & 4 MSB as
O/P
PORTB=0X00;
while(PORTB==0x0f); // Get the ROW value
ScanRow();
TRISB=0Xf0; // Enable the 4 LSB as O/P & 4 MSB as I/P
PORTB=0X00;
while(PORTB==0xf0); // Get the Column value
ScanCol();
DelayMs(1000); //provide a delay of 1s
Count[Row][Col]++; // Count the Pressed key
LCD_Cmd(0X01); //clear the LCD
LCD_Cmd(0X80); //1st row of the LCD
LCD_SendDataByte(KeyArray[Row][Col]); //send keypad value and display on LCD
DelayMs(1000); //provide delay of 1s
}
}
void ScanRow() // Row Scan Function
{
switch(PORTB)
{
case 0x07:
Row=3; // 4th Row
break;
case 0x0b:
Row=2; // 3rd Row
break;
case 0x0d:
Row=1; // 2nd Row
break;
case 0x0e:
Row=0; // 1st Row
break;
}
}
void ScanCol() // Column Scan Function
{
switch(PORTB)
{
case 0x70:
Col=3; // 4th Column
break;
case 0xb0:
Col=2; // 3rd Column
break;
case 0xd0:
Col=1; // 2nd Column
break;
case 0xe0:
Col=0; // 1st Column
break;
}
}
/*LCD CODE*/
void LCD_Delay() //delay routine
{
__delay_ms(1);
}
void LCD_Cmd(unsigned char cmd) //this function is to write command to the LCD
{
PORTB=cmd;
RS=0; //Set RS pin to low in order to send a
command to the LCD
EN=1; //set EN pin to high in order to send high pulse
LCD_Delay(); //give a small delay
EN=0; //set EN pin to low in order to make pulse low
LCD_Delay(); //give a small delay
}
void LCD_Init() //Initializing LCD
{
unsigned char cmd[5]={0X38,0X06,0X0F,0X01,0X80},Count;
//0x38 represents 5x7 matrix ,0x06 represent entry mode,0x0f represent display on cursor blinking,0x01 represents clearing the LCD,0x80 represents 1st row
for(Count=0;Count<5;Count++)
LCD_Cmd(cmd[Count]);
}
void LCD_SendDataByte(unsigned char data) //this function is to write a byte on LCD
{
PORTB=data;
RS=1; //make RS pin high inorder to send a data
EN=1; //set enable pin to high in order to send high
to low pulse
LCD_Delay(); //provide a small delay
EN=0;
LCD_Delay();
}
void LCD_Display( char *addr) //this function is to display a string on LCD
{
while(*addr)
{
LCD_SendDataByte(*addr);
addr++;
}
}
Lab7. Interfacing 7segment
I/O connection:
A,B,C,D,E,F,G,DP->B0 to B7
DIG1,DIG2,DIG3,DIG4 ->A0 to A3
#include<htc.h>
#define CNTRL_PORT PORTA
#define DATA_PORT PORTB
void hex2dec(unsigned char); //function to convert hex value to decimal
void send_seg(unsigned char,unsigned char,unsigned char,unsigned char); //Function to display count on 7seg
void DelayMs(unsigned int); //function to provide delay
unsigned char x;
unsigned char thou=0,hun=0,ten=0,single=0;
unsignedcharCA[10] = {0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90};
unsignedchar CC[10] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};
unsigned char CA_CNTRL[4] = {0x07,0x0b,0x0d,0x0e};
unsigned char CC_CNTRL[4] = {0x08,0x04,0x02,0x01};
unsigned char n=1;
void main()
{
unsigned char number;
nRBPU =0;
TRISB=0x00; //PORTB configured as O/P
ADCON1=0x07; //Configure PORTA & PORTE as Digital
port
TRISA=0x00; //PORTA Configured as O/P
while(1)
{
if(x == 200)
{
x=0;
single++; //Increment up to 9 in unit place
if(single>9)
{
single=0;
ten++; //Increment up to 9 in Tenth place
if(ten>9)
{
ten=0;
hun++; //Increment up to 9 in Hundredth place
if(hun>9)
{
hun=0;
thou++; //Increment up to 9 in Thousandth place
if(thou>9)
thou=0;
}
}
}
}
x++;
send_seg(thou,hun,ten,single);
}
}
void send_seg(unsigned char thou,unsigned char hun,unsigned char ten,unsigned char single)
{
if(n==1)
{
CNTRL_PORT=CA_CNTRL[0]; //Eanble Unit place 7-Segment
DATA_PORT=CA[single]; //Display Unit Place Number
n=2;
DelayMs(5);
}
else if(n==2)
{
CNTRL_PORT=CA_CNTRL[1]; //Eanble Tenth place 7-Segment
DATA_PORT=CA[ten]; //Display Tenth Place Number
n=3;
DelayMs(5);
}
else if(n==3)
{
CNTRL_PORT=CA_CNTRL[2]; //Enable Hundredth place 7-Segment
DATA_PORT=CA[hun]; //Display Hundredth Place Number
n=4;
DelayMs(5);
}
else if(n==4)
{
CNTRL_PORT=CA_CNTRL[3]; //Eanble Thousandth place 7-Segment
DATA_PORT=CA[thou]; //Display Thousandth Place Number
n=1;
DelayMs(5);
}
}
void DelayMs(unsigned int Ms)
{
int delay_cnst;
while(Ms>0)
{
Ms--;
for(delay_cnst = 0;delay_cnst <220;delay_cnst++);
}
}
I/Oconnection:
Vin of GSM->12v
Ground of GSM->Ground
D0,D1 of GSM->TX,RX
#define
<htc.h>
#define
_XTAL_FREQ 20000000 //crystal frequency of 20MHZ
#include
"uart.h"
//header file
#include
"string.h"
//header file
char
UART_Init(const long int baudrate)
{
unsigned int x;
x = (_XTAL_FREQ - baudrate*64)/(baudrate*64);
if(x>255)
{
x = (_XTAL_FREQ - baudrate*16)/(baudrate*16);
BRGH = 1; //High Baud
Rate Select bit set to high
}
if(x<256)
{
SPBRG = x; //Writing SPBRG register
SYNC = 0; //Selecting Asynchronous Mode
SPEN = 1; //enables serial port
TRISC7 = 1;
TRISC6 = 1;
CREN = 1; //enables continuous reception
TXEN = 1; //enables continuous transmission
return 1;
}
return 0;
}
char UART_TX_Empty()
{
return TRMT; //Returns Transmit Shift Status bit
}
char
UART_Data_Ready()
{
return RCIF; //Flag bit
}
char UART_Read() //this function is used to read a byte
{
while(!RCIF); //Waits for Reception to complete
return RCREG; //Returns the 8 bit data
}
void
UART_Read_Text(char *Output, unsigned int length)
//this function is used to read a text
{
int i;
for(int i=0;i<length;i++)
Output[i] = UART_Read();
}
void
UART_Write(char data) //this function
is used to write a byte
{
while(!TRMT);
TXREG = data; //transmit register
}
void
UART_Write_Text(char *text) //this function is used to write a string
{
int i;
for(i=0;text[i]!='\0';i++)
UART_Write(text[i]);
}
void main()
{
UART_Init(9600); //initialize the UART function
__delay_ms(1000); //provide the delay of 1s
while(1) //infinite loop
{
__delay_ms(1000); //provide a
delay of 1s
UART_Write_Text("AT"); //attention
command
UART_Write(13); //enter
UART_Write(10); //carriage return
__delay_ms(1000); //provide delay
of 1s
UART_Write_Text("AT+CMGF=1"); //initialize
the modem
UART_Write(13); //enter
UART_Write(10); //carriage
return
__delay_ms(1000); //provide delay
of 1s
UART_Write_Text("AT+CMGS=\"1234567890\"");
//send a message
UART_Write(13); //enter
UART_Write(10); //carriage
return
__delay_ms(1000); //provide delay
of 1s
UART_Write_Text("GSM"); //display on hyper
terminal
UART_Write(13); //enter
UART_Write(10); //carriage
return
__delay_ms(1000); //provide delay
of 1s
UART_Write(26);
//Ctr +Z
}
}
Lab 9. Interfacing RELAY to turn the relays ON and OFF
I/O
connection:
B0,B1,B2,B3 ->
to relay shield.
#define
_XTAL_FREQ 20000000 //crystal frequency of 20MHZ
#include
"uart.h"
//header file
#include
"string.h" //header file
#define
relay1 RB1
#define
relay2 RB2
#define
relay3 RB3
#define
relay4 RB4
char
UART_Init(const long int baudrate)
{
unsigned int x;
x = (_XTAL_FREQ -
baudrate*64)/(baudrate*64);
if(x>255)
{
x = (_XTAL_FREQ - baudrate*16)/(baudrate*16);
BRGH = 1; //High Baud
Rate Select bit set to high
}
if(x<256)
{
SPBRG = x; //Writing SPBRG register
SYNC = 0; //Selecting Asynchronous Mode
SPEN = 1; //enables serial port
TRISC7 = 1;
TRISC6 = 1;
CREN = 1; //enables continuous reception
TXEN = 1; //enables continuous transmission
return 1;
}
return 0;
}
char UART_TX_Empty()
{
return TRMT; //Returns Transmit Shift Status bit
}
char
UART_Data_Ready()
{
return RCIF; //Flag bit
}
char UART_Read() //this function is used to read a byte
{
while(!RCIF); //Waits for Reception to complete
return RCREG; //Returns the 8 bit data
}
void
UART_Read_Text(char *Output, unsigned int length)//this function is used to read a
text
{
int i;
for(int i=0;i<length;i++)
Output[i] = UART_Read();
}
void
UART_Write(char data) //this function is used to write a byte
{
while(!TRMT);
TXREG = data; //transmit
register
}
void
UART_Write_Text(char *text) //this function is used to write a string
{
int i;
for(i=0;text[i]!='\0';i++)
UART_Write(text[i]);
}
void main()
{
unsigned char
ReceivChar;
TRISB=0X00; //make register
as the output
PORTB=0X00; //make the
PORTB as the output port
UART_Init(9600); //inititalise
the UART
DelayMs(1000); //provide delay of 1s
while(1)
{
if(UART_Data_Ready())
//check if the
data is ready
{
ReceivChar = UART_Read();
//store
the data in a variable
UART_Write(ReceivChar); //display on hyperterminal
__delay_ms(1000); //provide delay of 1s
if(ReceivChar=='1') //check if the received char is 1if 1
{
ReceivChar = UART_Read(); //store the data in a variable
UART_Write(ReceivChar); //display on
hyperterminal
if(ReceivChar=='N') //if received character is N
relay1=1; //turn ON the 1st relay
else if(ReceivChar=='F') //if received character is F
relay1=0; //turn OFF the 1st relay
}
else if(ReceivChar=='2') //check if the received char is 2if 2
{
ReceivChar =
UART_Read(); //store the data in a variable
UART_Write(ReceivChar); //display on hyperterminal
if(ReceivChar=='N') //if received character is N
relay2=1; //turn ON the 2nd relay
else if(ReceivChar=='F') //if received character is F
relay2=0; //turn OFF the 2nd relay
}
else if(ReceivChar=='3') //check if the received char is 3if 3
{
ReceivChar = UART_Read(); //store the data in a variable
UART_Write(ReceivChar);
//display on hyperterminal
if(ReceivChar=='N') //if received character is N
relay3=1; //turn ON the 3rd relay
else if(ReceivChar=='F')
//if
received character is N
relay3=0; //turn OFF the 3rd relay
}
else
if(ReceivChar=='4') //check if
the received char is 4if 4
{
ReceivChar = UART_Read(); //store the data in a variable
UART_Write(ReceivChar);
//display on hyperterminal
if(ReceivChar=='N') //if received character is N
relay4=1; //turn ON the 4th relay
else if(ReceivChar=='F') //if received character is N
relay4=0; //turn OFF the 4th relay
}
