HELP...problems in c code........... atmega 8 : 8051 Microcontroller Projects AVR PIC Projects Tutorials Ebooks Libraries codes

Forums

8051 Microcontroller Projects AVR PIC Projects Tutorials Ebooks Libraries codes :: Forums :: Discuss and Learn :: AVR Discussion Forum		<< Previous thread \| Next thread >>
HELP...problems in c code........... atmega 8


Moderators: Ajay, Junied , abbas1707, Arun Kumar V, pdi33, Shailesh NAYAK, ۞ TPS ۞, shyam, sashijoseph

Author

Post

pravin_35

Mon Dec 22 2008, 11:12PM

Registered Member #13089

Joined: Sat Dec 13 2008, 10:20PM

Posts: 39
Thanked 0 times in 0 posts

hi...... i am new to atmega avr family......... i hav written a code in avr studio to generate somme microsecond delay........... but while debugging its works only one time... its not responding the flag set...... plz help me.............? i also tried via interrupt also same problem............

// generate a us delay //

#include<avr\io.h>

void delay();

int main()
{

SPL=0X00;
SPH=0X04;
while(1)
{

DDRB=0XFF;
PORTB=~PORTB;
delay();
}

return 0;
}

void delay (void)
{
TCNT0=0x00;
TCCR0=0x01;
while (TIFR==0X00);
TIFR =0X01;
}

pravin

pdi33

Tue Dec 23 2008, 10:31AM

Registered Member #1329

Joined: Mon Jun 04 2007, 09:28AM

Posts: 773
Thanked 186 times in 181 posts

just change ur overflow flag checking from this:
while (TIFR == 0x00);
to
while ((TIFR & 0x01) == 0x00);

i have checked it on proteus and works well with the mega8.
Also u need to define the data direction of PORTB as output only once during startup so preferably keep it outside the infinite loop . Another point is u need not define the stack pointer in c-programs as the compiler will take care of it much efficiently .