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Hi everyone,

I wanna write an integer (i.e 429) to a variable. Everytime I press a button on the keypad
it calls ISR(INT2_vect) to display the number on the keypad. I already tried doing
this with the scanf function but din not work. I also tried pressing a button and then
disabling the interrupt, press three numbers and read them but again did not work.
I'm doing this in C language and using WinAVR GCC compiler. This is how I
have everything connected.

keypad - encoder - atmega32 - LCD

Any suggestions???

int main(void)
{
Initialize_Atmega32(); // set baud rate, enable txpin, etc
USART_Transmit_Clear_Screen(); // clear LCD screen

GICR &=~(1<<INT2); //disable external interrup //disable external interrup
MCUCSR |=(1<<ISC2); //rising edge
GIFR |=(1<<INT2); // clear flag
GICR |=(1<<INT2); // Enable INT2 interrupt, "should" call INT2_vect ISR when INT2 fires
sei(); // Enable global interrupts

while (1)
{
// waits for interrupt

}

return 0;
}

ISR(INT2_vect)
{
int x;
DDRA = 0x0F; // pins 4,5,6, and 7 of PORTA collect number in ATmega32
x = (PINA>>4);
switch (x)
{
case 3:
if ( (PINA>>4) == 3) // Press ENTER button to call INT2
{
GICR &=~(1<<INT2); // disable INT2 interrupt

Base_Rate1 = (PINA>>4);
delay_ms(5000); // delay 5 sec to try to press second digit on keypad

Base_Rate2 = (PINA>>4);
delay_ms(5000); // delay 5 sec to try to press third digit on keypad

Base_Rate3 = (PINA>>4);

strcpy(result, Base_Rate1); // concatenate three numbers together
strcat(result, Base_Rate2);
strcat(result, Base_Rate3);

printNumber((int)result); // display three numbers as an integer on LCD
}
break;

case 11:
x = 0;
printNumber(x); // display number 0
break;

case 13:
x = 1;
printNumber(x); // display number 1
break;

case 9:
x = 2;
printNumber(x); // display number 2
break;

case 5:
x = 3;
printNumber(x); // display number 3
break;

case 12:
x = 4;
printNumber(x);
break;

case 8:
x = 5;
printNumber(x);
break;

case 4:
x = 6;
printNumber(x);
break;

case 14:
x = 7;
printNumber(x);
break;

case 10:
x = 8;
printNumber(x);
break;

case 6:
x = 9;
printNumber(x);
break;

case 0:
USART_Transmit('.'); // display a dot (.)
break;
}
}

"Does not work" means what?

Is the keypad input smart? Usually, when one reads button presses in a uC, you have to account for the key bounce. A la when you get the interrupt, you wait for sth like 200ms to let the signal stabilise.

Maybe this will help a bit: http://www.atmel.com/dyn/resources/p...ts/doc1232.pdf
Or something else from here: http://www.atmel.com/dyn/products/ap...?family_id=607