Thread: using a single button input for multiple PWM Outputs

i am having some trouble setting up this code. i need to use an external interrupt to output 4 different PWM values and each button press must loop the PWM until the button is pressed again, but after setup i have no idea what to do next. any ideas?

Code:

/*
 * PWMdutycycle.c
 *
 * Created: 23/10/2020 12:39:40
 * Author : camog
 */ 

#include <avr/io.h>
#include <avr/interrupt.h>
#include "avr/iom328p.h"

#define OCR0A_0
#define OCR0A_1
#define OCR0A_2
#define OCR0A_3

void T0Interrupt1();
void T0interrupt2();
void T0interrupt3();
void T0interrupt4();

int main(void)
{
	DDRD | =  1<<PORTD6; /* OCR0A output port */
	PORTD &= ~ 1 << PORTD6; /* set OCR0A to 0 */
	
	DDRB &= ~ 1 << PORTD2;
	EIMSK = ( 1 << INT0 );
	EICRA |= ( 1 << ISC00, | 1 << ISC01 ); 
	
	TCCR0A | = ( 1<< WGM00, | 1 << WGM01, | 1<< COM0A1, | 1<< COM0A0); /* fast PWM mode, inverting mode set*/
	TCCR0B | = 1 << CS00; /* clk no prescaling */
	OCR0A_0 = 0;
	OCR0A_1 = 0x3F; /*duty cycle=63, for 25% for inverting mode*/
	OCR0A_2 = 0x9F;/*duty cycle=159, for 62.5%*/
	OCR0A_3 = 0xDF; /*duty cycle =223 for 87.5%*/
	
	sei();
	
    
    while (1);
}
ISR (INT0_vect)
 {
	 if (PIND2 == 1 )
	 {
		 OCR0A = OCR0A_1; 
	 }
	 else  (PIND2 = 0)
	 {
		 OCR0A = 0;
	 }
 }

So is it like this?

- press (and release) button, PWM pattern 1 starts.
- press (and release) button, PWM pattern 1 stops.
- press (and release) button, PWM pattern 2 starts.
- press (and release) button, PWM pattern 2 stops.

and so on.

Is your ISR attached to your button or your PWM pin?

I'm guessing you have something like this to test on (for example).
AVR Development Kit - Tutorials

It would be really useful if you posted the URL to the actual kit you're using, so we can see how things are configured etc.

A useful pre-cursor step would be to just have a single button, a single LED, and make the LED light in response to the button presses.

It's a highly iterative process, with small steps and lots of testing.
Because when things go wrong, it's hard to get any information at all out of the system.

Code:

else  (PIND2 = 0)

This line should raise an warning or maybe an error!

Tim S.