Potential Bug in Chapter 5 serialOrgan/organ.c

[vilroi]

If I understood correctly, playNote() is supposed to create a square wave with a period of period by toggling the SPEAKER_PORT, and continues to output the wave for duration.

If this is the case, shouldn't SPEAKER_PORT be toggled twice after half the amount of time for period has elapsed, as the period is the duration of a single cycle?

Thus instead of:

for (i = 0; i < period; i++) {
    _delay_us(1);
}
SPEAKER_PORT ^= (1 << SPEAKER);

I would assume it should be something like:

for (i = 0; i < 2; i++) {
    for (j = 0; j < period / 2; j++) {
        _delay_us()
    }
    SPEAKER_PORT ^= (1 << SPEAKER);
}

Please let me know If I have misunderstood how this is supposed to work.

Otherwise, thank you for your outstanding book.