C语言如何让调用笔记本的USB接口啊，求实例

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解决时间 2021-01-04 13:47

提问者网友：疯孩纸
2021-01-03 20:38

最佳答案

五星知识达人网友：千夜
2021-01-10 01:55

1.打开usb接口上的设备，或者打开usb控制器，涉及到windows的驱动访问。一般访问设备使用CreateFile打开设备，然后使用ReadFile/WriteFile读写设备。

2.例程：

    handle hFile = CreateFile(..., FILE_FLAG_overlapped, ...); //指定以异步方式打开
    byte bBuffer[100];
    overlapped o = { 0 };
    o.Offset = 345;
    bool bReadDone = ReadFile(hFile, bBuffer, 100, null, &o); // bReadDone 指定I/O请求是不是以同步方式打开
    dword dwError = GetLastError();
    if (!bReadDone && (dwError == ERROR_IO_PENDING)) { //异步方式打开
        // The I/O is being performed asynchronously; wait for it to complete
        WaitForSingleObject(hFile, infinite);
        bReadDone = TRUE;
    }
    if (bReadDone) {
           // o.Internal contains the I/O error
           // o.InternalHigh contains the number of bytes transferred
           // bBuffer contains the read data
    } else {
            // An error occurred; see dwError
    }

全部回答

1楼网友：玩世
2021-01-10 03:21

没有调用USB接口这种说法吧可以打开USB接口上的设备，或者打开USB控制器，那涉及到windows的驱动访问。一般访问设备使用CreateFile打开设备，然后使用ReadFile/WriteFile读写设备。比如： HANDLE hFile = CreateFile(..., FILE_FLAG_OVERLAPPED, ...); //指定以异步方式打开 BYTE bBuffer[100]; OVERLAPPED o = { 0 }; o.Offset = 345; BOOL bReadDone = ReadFile(hFile, bBuffer, 100, NULL, &o); // bReadDone 指定I/O请求是不是以同步方式打开 DWORD dwError = GetLastError(); if (!bReadDone && (dwError == ERROR_IO_PENDING)) { //异步方式打开 // The I/O is being performed asynchronously; wait for it to complete WaitForSingleObject(hFile, INFINITE); bReadDone = TRUE; } if (bReadDone) { // o.Internal contains the I/O error // o.InternalHigh contains the number of bytes transferred // bBuffer contains the read data } else { // An error occurred; see dwError }

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