C++ 向串口传输数据

// send_series.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
//

#include <iostream>
#include <Windows.h>
#include <atlstr.h>
using namespace std;

HANDLE hcom; //全局变量，串口句柄

int main()
{
    std::cout << "Start Test  .  .  .\n";

    hcom = CreateFile(L"COM4",        //COM4口
        GENERIC_READ | GENERIC_WRITE, //允许读和写
        0,    //独占方式
        NULL,
        OPEN_EXISTING, //打开而不是创建
        FILE_ATTRIBUTE_NORMAL, //同步
        NULL);
    if (hcom == INVALID_HANDLE_VALUE)
    {

        fprintf(stderr, "打开串口失败！\n");
        exit(0);
    }

    SetupComm(hcom, 1024, 1024);    //设置串行口的输入和输出缓冲区

    COMMTIMEOUTS TimeOuts; //设定超时
    TimeOuts.ReadIntervalTimeout = 1000;
    TimeOuts.ReadTotalTimeoutMultiplier = 500;
    TimeOuts.ReadTotalTimeoutConstant = 5000; //设定写超时
    TimeOuts.WriteTotalTimeoutMultiplier = 500;
    TimeOuts.WriteTotalTimeoutConstant = 2000;
    SetCommTimeouts(hcom, &TimeOuts); //设置超时

    DCB dcb;
    GetCommState(hcom, &dcb);
    dcb.BaudRate = 115200;  //波特率为115200
    dcb.ByteSize = 8; //通信字节位数，每个字节有8位
    dcb.Parity = 0; //无奇偶校验位
    dcb.StopBits = 1; //一个停止位
    SetCommState(hcom, &dcb); 
    
    PurgeComm(hcom, PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR | PURGE_RXCLEAR); 
    //清空缓冲区

    DWORD dwWrittenLen = 0;
    

    WriteFile(hcom, "*IDN? \n", strlen("*IDN? \n"), &dwWrittenLen, NULL);
    Sleep(2 * 1000);
    WriteFile(hcom, "RFO 2\n", strlen("RFO 2\n"), &dwWrittenLen, NULL);
    Sleep(2 * 1000);
    WriteFile(hcom, "RFO 1\n", strlen("RFO 1\n"), &dwWrittenLen, NULL);
    Sleep(2 * 1000);
    WriteFile(hcom, "RFO 3\n", strlen("RFO 3\n"), &dwWrittenLen, NULL);
    Sleep(2 * 1000);
    WriteFile(hcom, "RFO 4\n", strlen("RFO 4\n"), &dwWrittenLen, NULL);

    CloseHandle(
        hcom //handle to object to close
    );
    
    return 0;

}