femtosynth/main.cpp

#include "pipemini/pipemini.h"
#include <math.h>
#include <stdio.h>
#include <unistd.h>

#include "oscillator.cpp"

int main() {
    const int sample_rate = 48000;
    const float freq = 600.0f;
    float phase = 0.0f;
    int duration = 1;

    PipeMini audio;

    bool ok = audio.start([&](int16_t* left, int16_t* right) {
        float s = sinf(phase) * 0.25f; // quiet sine
        int16_t v = (int16_t)(s * 32767.0f);
        *left = v;
        *right = v;

        phase += 2.0f * 3.14159265f * freq / sample_rate;
        if (phase > 2.0f * 3.14159265f) phase -= 2.0f * 3.14159265f;
    }, sample_rate);

    if (!ok) {
        fprintf(stderr, "failed to start audio\n");
        return 1;
    }

    printf("playing %f Hz sine for %d seconds...\n", freq, duration);
    sleep(duration);

    return 0;
}