I have circuit setup, that turns the led on every time a button is pressed and it counts up from 0 to 255, so in binary 0000 0000 to 1111 1111. My switch is configured to PB2 which is D9 on the board.
I facing a problem, as you can see from my coud I am using 8 pins, 6 from D register and 2 from B register. When I increment PORTB and at some point it become 0b00000100, then its the same value as then input pin which is pb2 so in my infinite loop even though I am not pressing the button for PINB, it gets turned on. I tried resetting the values of PORTB to 0 but still it won't turn off.
I need a mechanism so when I increment PORTB it doesn't effect my input pin which is PB2.
Please any help is appreciate, I tried posting the video but its too big.
#include <avr/io.h>
#define F_CPU 16000000UL
#include <util/delay.h>
/*
Board digital I/O pin to atmega328 registers for LEDS
| d2 | d3 | d4 | d5 | d6 | d7 | d8 | d9 |
| pd2 | pd3 | pd4 | pd5 | pd6 | pd7 | pb0 | pd1 |
Input Button
| d9 |
| pb2 |
*/
int main(void) {
int x;
DDRD = 0b11111100;
PORTD = 0b00000000;
DDRB = 0b00000011;
PORTB = 0b00000100;
while(1) {
if((PINB & 0b00000100) == 0) {
if(x < 63) {
PORTD = PORTD + 0b00000100;
x++;
} else if (x == 63) {
x=0;
PORTD = 0b00000000;
PORTB = PORTB + 0b00000001;
//problem here, when PORTB is incremented to 0b00000100 then the switch turns on automatically
if((PORTB & 0b00000100) == 0b00000100) {
PORTB = 0b00000000;
PORTD = 0b00000000;
}
}
_delay_ms(80);
}
}
return 0;
}
The easy answer is to avoid using PORTB as a variable. Rather, use x, and shift the value in x appropriately to display it.
#include <avr/io.h>
#define F_CPU 16000000UL
#include <util/delay.h>
/*
Board digital I/O pin to atmega328 registers for LEDS
| d2 | d3 | d4 | d5 | d6 | d7 | d8 | d9 |
| pd2 | pd3 | pd4 | pd5 | pd6 | pd7 | pb0 | pd1 |
Input Button
| d9 |
| pb2 |
*/
int main(void) {
uint8_t x = 0;
DDRD = 0b11111100;
PORTD = 0b00000000;
DDRB = 0b00000011;
PORTB = 0b00000100;
while(1) {
if((PINB & 0b00000100) == 0) {
++x;
PORTD = x << 2;
PORTB = (PORTB & 0b11111100) | ((x >> 6) & 0b00000011);
}
_delay_ms(80);
}
return 0;
}