Help? about avr-programming

[hexagon5un]

Heya!

There's good stuff here: you set up the pullups, initialized the overall pin-interrupt (PCIE2), and test for both pins in the ISR. But the confusion here is that both buttons are controlling the same LED.

So when you test BUTTON, it sets the LED, and then the code goes directly to testing BUTTON3. This all happens so fast that you don't even notice that it's working on BUTTON. Try setting/clearing another LED on the other button and you should see that it works.

By the way, I really like this basic approach to learning code -- you build up as simply as possible on the code in the book. This way, a) you make the code your own, and b) you can push it until it breaks and you'll learn something deeper about the way the demo works. Sweet.

[hballinas]

Thank you Elliot. I am really enjoying your book and would be thrilled to be able to ask you more questions as I go along. I was able to make it work, 2 pins changing the state of the same LED by changing the condition as noted below. I don't know if this is public, but I include it for any other person going through your book as I am. The reason I wanted it this way is because I'm thinking about using an AVR to light up an AUTOART car model, and I need the doors to activate the interior light when the doors open. By the way, do you happen to know if the IRremote.h library can be used along with AVR Studio? If not, do you happen to know a library to use an IR remote with an AVR using C and not C++?

Code:
ISR(PCINT2_vect) { /Run every time there is a change on button... ISR is a macro that denotes a function of interrupt.h/
if (bit_is_set(BUTTON_PIN, BUTTON|BUTTON3)) //PIND, PD2//
{
LED_PORT &= ~(1 << LED1); //PORTB, PB1//
}
else {
LED_PORT |= (1 << LED1); //PORTB, PB1//
}