pic 16f877a counter operation in timer1.

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azarutz

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hi, i want to start the timer when a pin high and stop the timer when another pin high and display the count in lcd for that i written a c program in hi-tech c compiler . first i didnt know how to convert hex value to decimal . my program my simulation as follow in program display function i wrote to display the hex value but it didnt seem correct .
Code: 
#include <pic.h>
#define RS RB0
#define RW RB1
#define E RB2
void pic_init(void);
void lcd_init(void);
void delay(int);
void command(char);
void send_data(char);
void display(void);
int a=0,b=0,c=0,d=0,v;
void main()
{
	T1CON=0X18;
	TMR1H=0X3C;
    TMR1L=0xB0;
	pic_init();
	lcd_init();
	while(1)
	{  
		if(RC3==1)
		{
		 TMR1ON=1;
		 if(RC4==1)
		 {
			TMR1ON=0;
		 }	
	}
   display();
 }		
	
}
void pic_init(void)
{
	TRISA=0xff;
	PORTA=0x00;
	TRISB=0x00;
	PORTB=0x00;
	TRISD=0x00;
	PORTD=0x00;
}
void lcd_init(void)
{
	command(0x38);
	command(0x01);
	command(0x0c);
}
void command(char comm)
{
	PORTD=comm;
    RS=0; //register select
    RW=0;//read or write
    E=1; //enable data line
    delay(1000);
    E=0; //disable data line
   delay(1000);
}
void send_data(char data)
{
   PORTD=data;
   RS=1;
   RW=0;
   E=1;
   delay(1000);
   E=0;
   delay(1000);
}	
void display()
{ 
    command(0x80);
    //v=TMR1H;
    v=TMR1-0x3cb0;
    a=v/10;
    d=v%10;
    v=v/10;
    b=v%10;
    v=v/10;
    c=v%10;
    send_data(0x30+a);
    send_data(0x30+b);
    send_data(0x30+c);
    send_data(0x30+d);
}	
void delay(int d)
{
   int i;
   for(i=0;i<=d;i++);
}
 

You can try this function
Code: 
void print_number(unsigned int i)
{
	char u = 0;
	unsigned char lcd_buf[16];
	while(i) {
		lcd_buf[u++] = (i % 10 + '0');
		i /= 10;
	}
	while(u) 
                send_data(lcd_buf[--u]);
}
If you need to print long number of 32 bits then just need to change the int i to long int i.... But not required in your case....
 

You could use capture mode to retreive your data.
 

Hi , i included this function it shows error .
Code: 
#include <pic.h>
#define RS RB0
#define RW RB1
#define E RB2
void pic_init(void);
void lcd_init(void);
void delay(int);
void command(char);
void send_data(char);
void display(void);
void print_number(int);
int a=0,b=0,c=0,d=0,v,i;
unsigned char lcd_buf[17]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
void main()
{
	T1CON=0X18;
	//TMR1H=0X3C;
    //TMR1L=0xB0;
    TMR1=15536;
	pic_init();
	lcd_init();
	while(1)
	{  
		if(RC3==1)
		{
		 TMR1ON=1;
		 if(RC4==1)
		 {
			TMR1ON=0;
		 }	
	}
   display();
 }		
	
}
void pic_init(void)
{
	TRISA=0xff;
	PORTA=0x00;
	TRISB=0x00;
	PORTB=0x00;
	TRISD=0x00;
	PORTD=0x00;
}
void lcd_init(void)
{
	command(0x38);
	command(0x01);
	command(0x0c);
}
void command(char comm)
{
	PORTD=comm;
    RS=0; //register select
    RW=0;//read or write
    E=1; //enable data line
    delay(1000);
    E=0; //disable data line
   delay(1000);
}
void send_data(char data)
{
   PORTD=data;
   RS=1;
   RW=0;
   E=1;
   delay(1000);
   E=0;
   delay(1000);
}	
void display()
{ 
    command(0x80);
    i=TMR1H;
    //v=TMR1-0x3cb0;
    void print_number(unsigned int i)
  {
	char u = 0;
	unsigned char lcd_buf[16];
	while(i) {
		lcd_buf[u++] = (i % 10 + '0');
		i /= 10;
	}
	while(u) {
                send_data(lcd_buf[--u]);
}
	}
//    a=v/16;
//    d=v%16;
//    v=v/10;
//    b=v%10;
//    v=v/10;
//    c=v%10;
//    send_data(a);
//    send_data(0x30+b);
//    send_data(0x30+c);
//    send_data(0x30+d);
}	
void delay(int d)
{
   int i;
   for(i=0;i<=d;i++);
}

error:
Error [314] C:\Users\gobi\Desktop\New folder\pic\mplab\zcd_\duplicate.c; 77.1 ";" expected
Error [285] C:\Users\gobi\Desktop\New folder\pic\mplab\zcd_\duplicate.c; 98.1 no identifier in declaration
Warning [374] C:\Users\gobi\Desktop\New folder\pic\mplab\zcd_\duplicate.c; 98.1 missing basic type; int assumed
Error [314] C:\Users\gobi\Desktop\New folder\pic\mplab\zcd_\duplicate.c; 98.1 ";" expected
 

It seems you need to learn little more about the C programming.... For that you can check out the**broken link removed**.... The bible of C....


Don't put the code I provided inside another funtion.. Because it itself is a function... Just use it outside... just like the display function....
Then call the function with arguments as the hex which u want to print on lcd...
Also, in the declaration, use the same argument type as in the function definition...
ie
Code: 
void print_number(unsigned int);

Hope you understood...

-------------------------------------------------------------------------------------

for example,
like this:


Code: 
void print_number(unsigned int);
main()
{
     ........
     ........
     ........
     int a = 500;
     print_number(a);
     .......
     .......
}

void print_number(unsigned int num)
{
     ......
     ...... //this will print decimal value of a on LCD
     ......
}
 
Last edited:
oh sorry you are correct . i didnt understand hex to dec conversion it seems complex . i compiled with no error but my program didnt read correct value from TMR1 register , it shows some value .
Code: 
#include <pic.h>
#define RS RB0
#define RW RB1
#define E RB2
void pic_init(void);
void lcd_init(void);
void delay(int);
void command(char);
void send_data(char);
void display(void);
void print_number(unsigned int);
int a=0,b=0,c=0,d=0,v,i;
//unsigned char lcd_buf[17]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
void main()
{
	T1CON=0X18;
	//TMR1H=0X3C;
    //TMR1L=0xB0;
    TMR1=0x3cb0;
   //TMR1=0x3623;
	pic_init();
	lcd_init();
	while(1)
	{  
		if(RC3==1)
		{
		 TMR1ON=1;
		 if(RC4==1)
		 {
			TMR1ON=0;
		 }	
	}
   display();
  while(1);
 }		
	
}
void pic_init(void)
{
	TRISA=0xff;
	PORTA=0x00;
	TRISB=0x00;
	PORTB=0x00;
	TRISD=0x00;
	PORTD=0x00;
}
void lcd_init(void)
{
	command(0x38);
	command(0x01);
	command(0x0c);
}
void command(char comm)
{
	PORTD=comm;
    RS=0; //register select
    RW=0;//read or write
    E=1; //enable data line
    delay(1000);
    E=0; //disable data line
   delay(1000);
}
void send_data(char data)
{
   PORTD=data;
   RS=1;
   RW=0;
   E=1;
   delay(1000);
   E=0;
   delay(1000);
}	
void display()
{ 
    command(0x80);
    v=TMR1H;
    //v=TMR1-0x3cb0;
    print_number(v);
//    a=v/16;
//    d=v%16;
//    v=v/10;
//    b=v%10;
//    v=v/10;
//    c=v%10;
//    send_data(a);
//    send_data(0x30+b);
//    send_data(0x30+c);
//    send_data(0x30+d);
}	
void print_number(unsigned int i)
  {
	char u = 0;
	unsigned char lcd_buf[16];
	while(i) {
		lcd_buf[u++] = (i % 10 + '0');
		i /= 10;
	}
	while(u) {
                send_data(lcd_buf[--u]);
}
}
void delay(int d)
{
   int i;
   for(i=0;i<=d;i++);
}
 

Code: 
Just check out ur main program:

while(1)
	{  
		if(RC3==1)
		{
		     TMR1ON=1;
		     if(RC4==1)
		     {
			TMR1ON=0;
		     }	
	       }
   display();
   while(1);
 }

Just think what will happen in this code.... And what you want actually?
 

i want to count the difference between two square signal , so that i am going for timer1 to count the difference . when i give 1st square wave to RC3 pin i.e making RC3 high timer gets on and another square wave i gave to RC4 pin while making high timer gets off .i chose prescaler 1:2 and and initial TMR1 value should to 15536 to get 50Hz frequency . i chose 50 hz for easy calculation . for that i made that code when that pin goes high timer gets on and another pin goes high timer gets off. i find a way to convert hex to dec now i cant find the difference . i think this term is not needed after display cal fun.
Code: 
while(1);
my square wave also 50 Hz .
 
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