#Nyan Board by @Radomir Dopieralski

[UPDATE] Video and code added

So this should be an easy one, right? Oh how I failed. I'm still not getting sounds out of it, after I played around with libraries and different Versions of arduino. It's always tones and timers that get me.

I first thought the pads next to the attiny45/85 where a pullup resistor - d'oh. Of course it didn't do anything. Now it at least blinks.

To fit on an attiny45 I had to change the code a bit.

this code works, see the comments:

const int LENGTH = 27;
const int NOTES[] PROGMEM = {
    65, 67, 70, 67, 74, 74, 72, 65, 67, 70, 67, 72, 72, 70, 69, 67, 65, 67, 70,
    67, 70, 72, 69, 65, 65, 72, 70
};
const int DURATIONS[] PROGMEM = {
    25, 25, 25, 25, 75, 75, 15, 25, 25, 25, 25, 75,
    75, 75, 25, 5, 25, 25, 25, 25, 100, 5, 75, 25,
    100, 5, 100, 200
};

void play() {
    float bps = (60.0 / 120) * 1000.0;
    for (int i = 0; i < LENGTH; ++i) {
        int note = pgm_read_word_near(NOTES + i);
        int duration = pgm_read_word_near(DURATIONS + i);
        
        int hertz = (int) (pow(2.0, ((note - 69.0) / 12.0)) * 440);
        tone(4, hertz, (long) (duration * bps / 100) - 10);
        delay((long) (duration * bps / 100));
        toggle_eyes();
    }
}

void toggle_eyes() {
    PORTB ^= ( 1 << PB3 );
}
 

void setup() {
    DDRB = ( 1 << PB3 );
    DDRB = ( 1 << PB4 );
}

void loop() {
    play();
}

#include "pitches.h"
#include <avr/pgmspace.h>


const int FREQ[]  = {
    REST, NOTE_AS4, NOTE_AS5, NOTE_B4, NOTE_B5, NOTE_CS5, NOTE_CS6, NOTE_D5,
    NOTE_DS4, NOTE_DS5, NOTE_DS6, NOTE_E4, NOTE_E5, NOTE_E6, NOTE_FS4,
    NOTE_FS5, NOTE_GS4, NOTE_GS5,
};

const signed char INTRO_NOTES[] PROGMEM = {
9, 12, -15, -4, 9, 12, 15, 4, 6, 10, 6, 2, -4, -15, 9, 12, -15, -4, 6, 2,
4, 6, 13, 10, 13, 4, 0
};

const signed char MELODY_NOTES[] PROGMEM = {
-15, -17, 9, 9, 0, 3, 7, 5, 3, 0, -3, -5, -7, 7, 5, 3, 5, 9, 15, 17, 9, 15, 5,
9, 3, 5, 3, -9, -15, 17, 9, 15, 5, 9, 3, 7, 9, 7, 5, 3, 5, -7, 3, 5, 9, 15, 5,
9, 5, 3, -5, -3, -5, -15, -17, 9, 9, 0, 3, 7, 5, 3, 0, -3, -5, -7, 7, 5, 3, 5,
9, 15, 17, 9, 15, 5, 9, 3, 5, 3, -9, -15, 17, 9, 15, 5, 9, 3, 7, 9, 7, 5, 3, 5,
-7, 3, 5, 9, 15, 5, 9, 5, 3, -5, -3, -5, -3, 14, 16, -3, 14, 16, 3, 5, 9, 3,
12, 9, 12, 15, -3, -3, 14, 16, 3, 14, 12, 9, 5, 3, 14, 8, 11, 14, -3, 14, 16,
-3, 14, 16, 3, 3, 5, 9, 3, 14, 16, 14, -3, 3, 1, 3, 14, 16, 11, 12, 9, 12, 15,
-3, -1, -3, 14, 16, -3, 14, 16, 3, 5, 9, 3, 12, 9, 12, 15, -3, -3, 14, 16, 3,
14, 12, 9, 5, 3, 14, 8, 11, 14, -3, 14, 16, -3, 14, 16, 3, 3, 5, 9, 3, 14, 16,
14, -3, 3, 1, 3, 14, 16, 3, 12, 9, 12, 15, -3, -5
};

#define BEEP_PIN 4
#define LED_PIN 3
#define SPEED 1500


void toggle_eyes() {
    static bool blink = false;

    digitalWrite(LED_PIN, blink);
    blink = !blink;
}


void play(const signed char *notes, const unsigned int length) {
    for (unsigned int n = 0; n < length; n++) {
        signed char f = pgm_read_word_near(notes+n);
        int d;
        if (f < 0) {
            d = SPEED / 8;
            f = -f;
        } else {
            d = SPEED / 16;
        }
        tone(BEEP_PIN, FREQ[f], d);
        delay(1.3 * d);
        noTone(BEEP_PIN);
        toggle_eyes();
    }
}


void setup() {
    play(INTRO_NOTES, 26);
}


void loop() {
    play(MELODY_NOTES, 216);
}