ジェネレーター2

　WindowsPCのサウンド出力を使って可聴範囲のジェネレーターを作ることができましたがチャンネルが二つでは足りないので追加してみました。

　USBのオーディオ出力を接続しPC本体の出力と合わせてステレオ出力×２＝４チャンネルになります。

#include <iostream>
#include <string>
#include <windows.h>
#include <MMSystem.h>

#pragma comment (lib, "winmm.lib")

int main() {

    WAVEFORMATEX wfe;
    static HWAVEOUT hWaveOut;
    static WAVEHDR whdr;
    static LPBYTE lpWave;
    WAVEFORMATEX wfe2;
    static HWAVEOUT hWaveOut2;
    static WAVEHDR whdr2;
    static LPBYTE lpWave2;
    int i, len, start, end;
    int terms = 1;
    int sampling = 192000;
    int frequency = 500;

    wfe.wFormatTag = WAVE_FORMAT_PCM;
    wfe.nChannels = 2;
    wfe.wBitsPerSample = 8;
    wfe.nBlockAlign = wfe.nChannels * wfe.wBitsPerSample / 8;
    wfe.nSamplesPerSec = sampling;
    wfe.nAvgBytesPerSec = wfe.nSamplesPerSec * wfe.nBlockAlign;
    waveOutOpen(&hWaveOut, 0, &wfe, 0, 0, CALLBACK_NULL);
    lpWave = (LPBYTE)calloc(wfe.nAvgBytesPerSec, terms * wfe.nChannels);

    wfe2.wFormatTag = WAVE_FORMAT_PCM;
    wfe2.nChannels = 2;
    wfe2.wBitsPerSample = 8;
    wfe2.nBlockAlign = wfe2.nChannels * wfe2.wBitsPerSample / 8;
    wfe2.nSamplesPerSec = sampling;
    wfe2.nAvgBytesPerSec = wfe2.nSamplesPerSec * wfe2.nBlockAlign;
    waveOutOpen(&hWaveOut2, 2, &wfe2, 0, 0, CALLBACK_NULL);
    lpWave2 = (LPBYTE)calloc(wfe2.nAvgBytesPerSec, terms * wfe2.nChannels);

    // 立ち上がりは出力を0にする
    for (i = 0; i < sampling * terms * wfe.nChannels; i++) {
        lpWave[i] = 128;
        lpWave2[i] = 128;
    }

    len = sampling / frequency; 

    // 最初の8サイクルは出力しない
    start = len * 8 * wfe.nChannels;
    // 8サイクル波形を出力する
    end = start + len * 8 * wfe.nChannels;
    printf("start=%d, end=%d\n", start, end);

    for (i = start; i < end; i++) {
        if ((i % 2) == 0) {
            if ((i/2) % len < len / 2) { lpWave[i] = 228; }
            else { lpWave[i] = 28; }}}

    len /= 2;
    for (i = start; i < end; i++) {
        if ((i % 2) == 1) {
            if ((i / 2) % len < len / 2) { lpWave[i] = 228; }
            else { lpWave[i] = 28; }}}

    len *= 2;
    for (i = start; i < end; i++) {
        if ((i % 2) == 1) {
            if ((i / 2) % len < len / 2) { lpWave2[i] = 228; }
            else { lpWave2[i] = 28; }
        }
    }

    len /= 2;
    for (i = start; i < end; i++) {
        if ((i % 2) == 0) {
            if ((i / 2) % len < len / 2) { lpWave2[i] = 228; }
            else { lpWave2[i] = 28; }
        }
    }

    whdr.lpData = (LPSTR)lpWave;
    whdr.dwBufferLength = wfe.nAvgBytesPerSec * terms;
    whdr.dwFlags = WHDR_BEGINLOOP | WHDR_ENDLOOP;
    whdr.dwLoops = 1;
    waveOutPrepareHeader(hWaveOut, &whdr, sizeof(WAVEHDR));
    waveOutWrite(hWaveOut, &whdr, sizeof(WAVEHDR));

    whdr2.lpData = (LPSTR)lpWave2;
    whdr2.dwBufferLength = wfe.nAvgBytesPerSec * terms;
    whdr2.dwFlags = WHDR_BEGINLOOP | WHDR_ENDLOOP;
    whdr2.dwLoops = 1;
    waveOutPrepareHeader(hWaveOut2, &whdr2, sizeof(WAVEHDR));
    waveOutWrite(hWaveOut2, &whdr2, sizeof(WAVEHDR));

    char str[128];
    std::cout << "hello, world\n";
    std::cin >> str;

}

 

４チャンネルあればデータに１CH、制御に３CH使えるのでUSBにマイコンをつながなくても様々なデジタル部品の制御ができそうです。