Keypad interfacing problem with pic16f877a.

[HerohetoChakma]

This is an open letter to all member of this forum that i have designed a digital temperature monitoring system in which i can set two digits set point using a 4*3 keypad. My microcontroller is pic16f877a and LM35 sensor. I can not interface my keypad correctly. Could anybody help me by giving code in hi-tech c . It is very much need to me. I will be grateful for ever to u if u can solve this problem. This is an open request to you all. Iam also giving u my code. Some it work by sometimes this is not work. it say that simulation can't run due to excessive load. After trying 10- to 15 mins i can set only one time that also by trying more and more. Please help me.
//==========================================================================
// Author :Heroheto Chakma
// Project : Temperature Monitoring System using LM35
// Project description : This project(DTMScode) will use PIC16F877A to measure temperature // from the sensor and display on the LCD. If the temperature reaches // certain temp, it will trigger the LEDs and buzzer.
//==========================================================================
//==================include=================================
#include <pic.h>
#include <math.h>
//===============configuration==============================
__CONFIG (0x3F32);
//===============define IO port=============================
#define lcd PORTD
#define RS RB4
#define E RB5
#define led1 RB6
#define redled RB7
#define CHANNEL0 0b10000001 // AN0
#define CHANNEL1 0b10001001 // AN1
#define buzzer RB2
#define orangeled RB3
#define greenled RB0
//==============FUNCTION PTOTOTYPE=========================
void e_pulse(void);
void delay(unsigned short i);
void send_char(unsigned char data);
void send_string(const char *s);
void send_config(unsigned char data);
void lcd_goto(unsigned char data);
void lcd_clr(void);
void dis_num(unsigned long data);
void increment(unsigned long data);
void read_adc(void);
unsigned short read_temp(void);
void blink_LED1(unsigned char n);
void blink_redled(unsigned char n);
void blink_orangeled(unsigned char n);
void clearrow1(void);
void clearrow2(void);
void clearrow3(void);
void clearrow4(void);
void scancolumn1(void);
void scancolumn2(void);
void scancolumn3(void);
void scancolumn4(void);
void beep_once(void);
//====================MAIN================================
unsigned short result;
unsigned short temp;
float tempB,tempA;
unsigned char keyin[3]; //Declare an array to stall the keyin values
unsigned char num_count=0;
void main(void)
{
ADRESH=0; //clear A/D result
ADRESL=0; //clear A/D result
//setting ADCON1 Register
ADCON1=0b11000000; //A/D result right justified, //configure RA2 and RA5 as digital I/O
TRISA=0b11111111; //configure RA4 & RA5 as output
TRISB=0b00000000; //configure PORTB as output
TRISC=0b00001111; //set bit0-3 portC as input and bit4-7 as output
TRISD=0b00000000; //configure PORTD as output
TRISE=0b00000000; //configure PORTE as output
PORTA=0;
PORTB=0;
// setting the PWM
CCP1CON==0b00001100; //PWM mode
PR2=0xFF; //PWM Period setting/PWM frequency set as 4.88kHz
T2CON=0b00000101; //Timer2 on, prescale 4
CCPR1L=0;
//LCD Settings
send_config(0b00000001); //clear display at lcd
send_config(0b00000010); //Lcd Return to home
send_config(0b00000110); //entry mode-cursor increase 1
send_config(0b00001100); //diplay on, cursor off and cursor blink off
send_config(0b00111000); //function set
lcd_clr(); //clear LCD
delay(1000); //delay
lcd_goto(0); //initial display
send_string("PLEASE ENTER"); //Display "PLEASE ENTER" on lcd
lcd_goto(20); //Display on 2nd line
send_string("2 DIGIT SPEC");
while(1)
{ //keypad scanning
clearrow1(); //Clear 1st output pin and set the others
scancolumn1(); //scan column 1-4
clearrow2(); //Clear 2nd output pin and set the others
scancolumn2(); //scan column
clearrow3(); //Clear 3rd output pin and set the others
scancolumn3(); //scan column
clearrow4(); //Clear 4th output pin and set the others
scancolumn4(); //scan column
if(num_count==2)
{
delay(8000);
lcd_goto(0); //cursor start from beginning
//display character on LCD
send_char(' ');
send_char('S');
send_char('P');
send_char('E');
send_char('C');
send_char('.');
send_char('.');
send_char('=');
lcd_goto(20); //cursor go to 2nd line of the LCD
//display character on LCD
send_char(' ');
send_char('M');
send_char('E');
send_char('A');
send_char('S');
send_char('U');
send_char('R');
send_char('E');
send_char('D');
send_char('=');
while(1) //infinity loop
{
//keypad value
ADCON0=CHANNEL1;
lcd_goto(9);
keyin[2]=0;
tempA=(keyin[0]-0x30)*10+(keyin[1]-0x30);
dis_num((unsigned long)round(tempA));
send_char(0b11011111); //to set in degree celcius
send_char('C');
send_char(' ');
send_char(' ');
//sensor B the LM35 sensor
ADCON0=CHANNEL0; //CHANNEL1=0b10001001
lcd_goto(31);
read_adc();
temp=read_temp();
tempB=(((float)temp)*0.48876);
dis_num((unsigned long)round(tempB));
send_char(0b11011111);
send_char('C');
send_char(' ');
send_char(' ');
if(tempB<tempA) //when temperature is below spec
{
if((tempB+5)>=tempA) //when temperature is within 5 //degrees of spec
{
led1=1;
blink_LED1(10);
greenled=1;
orangeled=1;
blink_orangeled(3);
redled=0;
buzzer=0;
}
else
{
led1=1;
blink_LED1(10);
greenled=1;
orangeled=0;
redled=0;
buzzer=0;
}
}
else if(tempB>tempA) //when temperature over spec
{
led1=1; //turn on led1
//blink LED1 for 3 times
blink_LED1(3);
greenled=0;
orangeled=1;
blink_orangeled(3);
redled=1;
//blink redled for 3 times
blink_redled(3);
buzzer=1;
//beep_once();
}
delay(2000);
}
}
}
}
//=============================================================================
// Keypad scanning functions
//=============================================================================
void clearrow1(void) //clear the 1st row and set the others
{
RC7=0; //RC7,RC6,RC5 and RC4 are the output pins from PIC which //connect to 4 pins of keypad
RC6=1;
RC5=1;
RC4=1;
}
void clearrow2(void) //clear the 2nd row and set the others
{
RC7=1;
RC6=0;
RC5=1;
RC4=1;
}
void clearrow3(void) //clear the 3rd row and set the others
{
RC7=1;
RC6=1;
RC5=0;
RC4=1;
}
void clearrow4(void) //clear the 4th roW and set the others
{
RC7=1;
RC6=1;
RC5=1;
RC4=0;
}
void scancolumn1(void)
{
if(RC0==0) //if key '1' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st word
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of nuum_count //variable
send_char('1'); //Display the symbol '1' at LCD
keyin[num_count]='1'; //Stall the '1' value at the keyin array
num_count+=1; //increase the num_count variable's value by 1 //and the result stall back to the variable
delay(200);
}
else if(RC1==0) //if key '2' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('2'); //Display the symbol '2' at LCD
keyin[num_count]='2'; //Stall the '2' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
else if(RC2==0) //if key '3' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('3'); //Display the symbol '3' at LCD
keyin[num_count]='3'; //Stall the '3' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
}
void scancolumn2(void)
{
if(RC0==0) //if key '4' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('4'); //Display the symbol '4' at LCD
keyin[num_count]='4'; //Stall the '4' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
else if(RC1==0) //if key '5' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('5'); //Display the symbol '5' at LCD
keyin[num_count]='5'; //Stall the '5' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
else if(RC2==0) //if key '6' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('6'); //Display the symbol '6' at LCD
keyin[num_count]='6'; //Stall the '6' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
}
void scancolumn3(void)
{
if(RC0==0) //if key '7' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('7'); //Display the symbol '7' at LCD
keyin[num_count]='7'; //Stall the '7' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
else if(RC1==0) //if key '8' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('8'); //Display the symbol '8' at LCD
keyin[num_count]='8'; //Stall the '8' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
else if(RC2==0) //if key '9' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('9'); //Display the symbol '9' at LCD
keyin[num_count]='9'; //Stall the '9' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
}
void scancolumn4(void)
{
if(RC0==0) //if key '*' is being pressed
{
while(RC0==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('*'); //Display the symbol '*' at LCD
keyin[num_count]='*'; //Stall the '*' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
else if(RC1==0) //if key '0' is being pressed
{
while(RC1==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('0'); //Display the symbol '0' at LCD
keyin[num_count]='0'; //Stall the '0' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
else if(RC2==0) //if key '#' is being pressed
{
while(RC2==0)continue; //waiting the key to be released
if(num_count==0)lcd_clr(); //Clear the LCD if the key is the 1st password
lcd_goto(num_count); //The cursor of LCD points to the column //equivalent to the value of password_count //variable
send_char('#'); //Display the symbol '#' at LCD
keyin[num_count]='#'; //Stall the '#' value at the keyin_char array
num_count+=1; //increase the Password_count variable's value //by 1 and the result stall back to the variable
delay(200);
}
}
//==================subroutine LCD setting ==========================
void send_config(unsigned char data)
{
RS=0;
lcd=data;
delay(500);
e_pulse();
}
void e_pulse(void)
{
E=1;
delay(500);
E=0;
delay(500);
}
void send_char(unsigned char data)
{
RS=1;
lcd=data;
delay(500);
e_pulse();
}
void lcd_goto(unsigned char data)
{
if(data<16)
{
send_config(0x80+data);
}
else
{
data=data-20;
send_config(0xc0+data);
}
}
void lcd_clr(void)
{
RS=0;
send_config(0x01);
delay(600);
}
void send_string(const char *s)
{
unsigned char i=0;
while (s && *s)send_char (*s++);
}
void dis_num(unsigned long data)
{
unsigned char hundred_thousand;
unsigned char ten_thousand;
unsigned char thousand;
unsigned char hundred;
unsigned char tenth;
hundred_thousand = data/100000;
data = data % 100000;
ten_thousand = data/10000;
data = data % 10000;
thousand = data / 1000;
data = data % 1000;
hundred = data / 100;
data = data % 100;
tenth = data / 10;
data = data % 10;
if(hundred_thousand>0)
{
send_char(hundred_thousand + 0x30); //0x30 added to become ASCII code
send_char(ten_thousand + 0x30);
send_char(thousand + 0x30);
send_char(hundred + 0x30);
send_char(tenth + 0x30);
send_char(data + 0x30);
}
else if(ten_thousand>0)
{
send_char(ten_thousand + 0x30); //0x30 added to become ASCII code
send_char(thousand + 0x30);
send_char(hundred + 0x30);
send_char(tenth + 0x30);
send_char(data + 0x30);
}
else if(thousand>0)
{
send_char(thousand + 0x30); //0x30 added to become ASCII code
send_char(hundred + 0x30);
send_char(tenth + 0x30);
send_char(data + 0x30);
}
else if(hundred>0)
{
send_char(hundred + 0x30); //0x30 added to become ASCII code
send_char(tenth + 0x30);
send_char(data + 0x30);
}
else if(tenth>0)
{
send_char(tenth + 0x30); //0x30 added to become ASCII code
send_char(data + 0x30);
}
else send_char(data + 0x30); //0x30 added to become ASCII code
}
void increment(unsigned long data)
{
unsigned short j;
for(j=10;j>0;j--)
{ lcd_goto(32);
data=data+1;
dis_num(data);
delay(10000);
}
}
//==================subroutine ADC=========================
void read_adc(void)
{
unsigned short i;
unsigned long result_temp=0;
for(i=2000;i>0;i-=1) //looping 2000 times for getting average value
{
ADGO = 1; //ADGO is the bit 2 of the ADCON0 register
while(ADGO==1); //ADC start, ADGO=0 after finish ADC progress
result=ADRESH;
result=result<<8; //shift to left for 8 bit
result=result|ADRESL; //10 bit result from ADC
result_temp+=result;
}
result = result_temp/2000; //getting average value
}
unsigned short read_temp(void)
{
unsigned short temp;
temp=result;
return temp;
}
//==================subroutine DELAY==========================
void delay(unsigned short i)
{
for(;i>0;i--);
}
//==================led blinking============================
void blink_LED1(unsigned char n)
{
//loop for n times
for(n+=1;n>0;n-=1)
{
//set LED1 to 1
led1=1;
//short delay
for(unsigned int i=0;i<20000;i+=1); //max value is 65535
//set LED1 to 1
led1=0;
//short delay
for(unsigned int i=0;i<20000;i+=1); //max value is 65535
}
}
//function to blink redled for n times
void blink_redled(unsigned char n)
{
//loop for n times
for(n+=1;n>0;n-=1)
{
//set redled to 1
redled=1;
//short delay
for(unsigned int i=0;i<20000;i+=1); //max value is 65535
//set redled to 1
redled=0;
//short delay
for(unsigned int i=0;i<20000;i+=1); //max value is 65535
}
}
//function to blink redled for n times
void blink_orangeled(unsigned char n)
{
//loop for n times
for(n+=1;n>0;n-=1)
{
//set redled to 1
orangeled=1;
//short delay
for(unsigned int i=0;i<20000;i+=1); //max value is 65535
//set redled to 1
orangeled=0;
//short delay
for(unsigned int i=0;i<20000;i+=1); //max value is 65535
}
}
//==================Buzzer Beeping============================
void beep_once(void)
{
buzzer=1;
delay(10);
buzzer=0;
delay(20);
buzzer=1;
delay(10);
buzzer=0;
}

 

[babar_ali]

Hi,

Here is a code for 4*4 keypad

char scan_keypad()
        {
        PORTD=0xEf;
		Delay5mS();
		
        switch(PORTD)
                {
                case 0xEE:while(PORTD==0xEE); return  '1'; break;
                
		case 0xed:while(PORTD==0xed); return  '2'; break;
                
		case 0xeb:while(PORTD==0xeb); return  '3'; break;
                
		case 0xE7:while(PORTD==0xE7); return  'A'; break;
                }
        
		PORTD=0xdf;
		
		Delay5mS();

        switch(PORTD)
                {
                case 0xde:while(PORTD==0xde); return  '4'; break;
                
		case 0xDD:while(PORTD==0xDD); return  '5'; break;
                
		case 0xdB:while(PORTD==0xdB); return  '6'; break;
                
		case 0xd7:while(PORTD==0xd7); return  'B'; break;
                }
        
		PORTD=0xbf;

		Delay5mS();
				
                switch(PORTD)
                {
                case 0xbE:while(PORTD==0xbE); return  '7'; break;
                
		case 0xbD:while(PORTD==0xbD); return  '8'; break;
                
		case 0xBB:while(PORTD==0xBB); return  '9'; break;
                
		case 0xb7:while(PORTD==0xb7); return  'C'; break;
                }
        
		PORTD=0x7f;
		
		Delay5mS();
		
        switch(PORTD)
                {
                case 0x7E:while(PORTD==0x7E); return  '*'; break;
                
		case 0x7D:while(PORTD==0x7D); return  '0'; break;
                
		case 0x7B:while(PORTD==0x7B); return  '#'; break;
                
		case 0x77:while(PORTD==0x77); return  '.'; break;
               }
return 'z'; // return nothing

        }

 

[HerohetoChakma]

Could u give me full program?

 

[babar_ali]

Hi,

Try this for your self. The forum is not a code sharing website. It is just to discuss knowledge and help out individuals by the experience one gained by practicing electronics.
I shared a chunk of code as I have seen many written in poor format and one cannot understand it clearly what and how are they doing.

Enjoy!

 

[HerohetoChakma]

i don't need ur help my code is write? "A little knowledge is dangerous things" it can be apply for u. m i right????????????????/

 

[babar_ali]

=HerohetoChakma;"A little knowledge is dangerous things"

If little knowledge is dangerous thing... then where is the man with SO MUCH knowledge to be out of danger...
Enjoy!