DmxShow/main.cpp

#include <iostream>
#include <windows.h>
#include <thread>
#include <chrono>

void generateRandomColors(unsigned char& r, unsigned char& g, unsigned char& b);

void sendDMXData(HANDLE hSerial, unsigned char* data, int length) {
    // Start with a DMX break condition
    EscapeCommFunction(hSerial, SETBREAK);
    std::this_thread::sleep_for(std::chrono::milliseconds(1)); // Break duration
    EscapeCommFunction(hSerial, CLRBREAK);
    std::this_thread::sleep_for(std::chrono::milliseconds(1)); // Mark-after-break duration

    // Write the start code followed by the DMX data
    DWORD bytesWritten;
    unsigned char startCode = 0;
    WriteFile(hSerial, &startCode, 1, &bytesWritten, NULL);
    WriteFile(hSerial, data, length, &bytesWritten, NULL);
}

int main() {
    // Open the serial port
    HANDLE hSerial = CreateFileA("\\\\.\\COM3", GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
    if (hSerial == INVALID_HANDLE_VALUE) {
        std::cerr << "Error opening COM3 port" << std::endl;
        return 1;
    }

    // Configure the serial port
    DCB dcbSerialParams = { 0 };
    dcbSerialParams.DCBlength = sizeof(dcbSerialParams);
    if (!GetCommState(hSerial, &dcbSerialParams)) {
        std::cerr << "Error getting COM3 state" << std::endl;
        CloseHandle(hSerial);
        return 1;
    }

    dcbSerialParams.BaudRate = 250000; // DMX512 uses 250000 baud
    dcbSerialParams.ByteSize = 8;
    dcbSerialParams.StopBits = TWOSTOPBITS; // DMX512 uses 2 stop bits
    dcbSerialParams.Parity = NOPARITY;

    if (!SetCommState(hSerial, &dcbSerialParams)) {
        std::cerr << "Error setting COM3 state" << std::endl;
        CloseHandle(hSerial);
        return 1;
    }

    // Set timeouts
    COMMTIMEOUTS timeouts = { 0 };
    timeouts.ReadIntervalTimeout = 50;
    timeouts.ReadTotalTimeoutConstant = 50;
    timeouts.ReadTotalTimeoutMultiplier = 10;
    timeouts.WriteTotalTimeoutConstant = 50;
    timeouts.WriteTotalTimeoutMultiplier = 10;

    if (!SetCommTimeouts(hSerial, &timeouts)) {
        std::cerr << "Error setting COM3 timeouts" << std::endl;
        CloseHandle(hSerial);
        return 1;
    }

    srand(static_cast<unsigned int>(time(nullptr)));

    // DMX data (512 channels, all set to 255)
    const int num_channels = 512;
    unsigned char buffer[num_channels];
    memset(buffer, 255, sizeof(buffer)); // Fill the buffer with 255

    // Send DMX data in an infinite loop
    while (true) {
        // Generate and send random colors for channels 1, 2, and 3
        generateRandomColors(buffer[0], buffer[1], buffer[2]);

        // Send DMX data with random colors
        sendDMXData(hSerial, buffer, num_channels);
        std::this_thread::sleep_for(std::chrono::milliseconds(25)); // DMX refresh rate
    }

    // Close the serial port
    CloseHandle(hSerial);

    return 0;
}

void generateRandomColors(unsigned char& r, unsigned char& g, unsigned char& b) {
    r = rand() % 256;
    g = rand() % 256;
    b = rand() % 256;
}