访问USB端口的程序

  如果你想打开一个USB管道，你首先要知道这种USB设备的GUID和管道名称，获取句柄以后就可以使用ReadFile/WriteFile进行读写了！
以下是代码，请参考！！

// filename是管道名称，如pipe01等
int CUSBImpObject::open_file( char *filename)
{

int successOpened = 0,i;
int NumOpened;
HANDLE h;
NumOpened=OpenAllUsbDevices((LPGUID) &GUID_CLASS_I82930_BULK);
if(NumOpened<=0)
return 0;
for(i=0;i<NumOpened;i++){
strcat (outnamebuf,
"//"
);

strcat (outnamebuf,
filename
);

h= CreateFile(outnamebuf,
GENERIC_WRITE | GENERIC_READ,
FILE_SHARE_WRITE | FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
0,
NULL);
if (h == INVALID_HANDLE_VALUE) {
handUsbArray=NULL;
} else {
handUsbArray=h;
successOpened++;
}
}
return successOpened;
}

int CUSBImpObject::OpenAllUsbDevices(LPGUID pGuid) //打开所有的GUID为
pGuid的USB器件
{ //输出名存在outnamebuf中
ULONG NumberDevices;
HANDLE hOut = INVALID_HANDLE_VALUE; //HANDLE Phout[8];
HDEVINFO hardwareDeviceInfo;
SP_INTERFACE_DEVICE_DATA deviceInfoData;
ULONG i,flag=1,j;
ULONG NumDevicesOpened=0;
BOOLEAN done;
PUSB_DEVICE_DESCRIPTOR usbDeviceInst;
PUSB_DEVICE_DESCRIPTOR *UsbDevices = &usbDeviceInst;
char DeviceName[256]=""; //器件名

*UsbDevices = NULL;
UsbDevicesOpened = 0; //打开器件数置零

hardwareDeviceInfo = SetupDiGetClassDevs (
pGuid,
NULL, // Define no enumerator (global)
NULL, // Define no
(DIGCF_PRESENT | // Only Devices present
DIGCF_INTERFACEDEVICE)); // Function class devices.

NumberDevices = 4;
done = FALSE;
deviceInfoData.cbSize = sizeof (SP_INTERFACE_DEVICE_DATA);
i=0 ;
while (!done) {
NumberDevices *= 2;

if (*UsbDevices) {
*UsbDevices =
(struct _USB_DEVICE_DESCRIPTOR *)realloc (*UsbDevices, (NumberDevices *
sizeof (USB_DEVICE_DESCRIPTOR)));
} else {
*UsbDevices = (struct _USB_DEVICE_DESCRIPTOR *)calloc (NumberDevices,
sizeof (USB_DEVICE_DESCRIPTOR));
}

if (NULL == *UsbDevices) {
SetupDiDestroyDeviceInfoList (hardwareDeviceInfo);
return 0 ;
}

usbDeviceInst = *UsbDevices + i;

for (; i < NumberDevices; i++) {
if (SetupDiEnumDeviceInterfaces (hardwareDeviceInfo,
0,
pGuid,
i,
&deviceInfoData))
{
hOut = OpenOneDevice (hardwareDeviceInfo, &deviceInfoData, DeviceName);
if ( hOut != INVALID_HANDLE_VALUE )
{
handUsbArray[UsbDevicesOpened]=hOut;

if(!outnamebuf[UsbDevicesOpened])
{
return 0;
}
for(j=0;j<256;j++)
{
*(outnamebuf[UsbDevicesOpened]+j)=*(DeviceName+j);
*(DeviceName+j)=0;
}
UsbDevicesOpened++;
}
}
else
{
if(ERROR_NO_MORE_ITEMS == GetLastError())
{
done = TRUE;
break;
}
}

} //end for
} //end while
SetupDiDestroyDeviceInfoList (hardwareDeviceInfo);
free ( *UsbDevices );
return UsbDevicesOpened ;

}

//--------------------------------------------------------------------
//
//
//
//--------------------------------------------------------------------
HANDLE CUSBImpObject::OpenOneDevice (
IN HDEVINFO HardwareDeviceInfo,
IN PSP_INTERFACE_DEVICE_DATA DeviceInfoData,
IN char *devName
)
{
PSP_INTERFACE_DEVICE_DETAIL_DATA functionClassDeviceData = NULL;
ULONG predictedLength = 0;
ULONG requiredLength = 0;
HANDLE hOut = INVALID_HANDLE_VALUE;
SetupDiGetInterfaceDeviceDetail (
HardwareDeviceInfo,
DeviceInfoData,
NULL, // probing so no output buffer yet
0, // probing so output buffer length of zero
&requiredLength,
NULL); // not interested in the specific dev-node

predictedLength = requiredLength;

functionClassDeviceData =(struct _SP_DEVICE_INTERFACE_DETAIL_DATA_A *)
malloc (predictedLength);
functionClassDeviceData->cbSize = sizeof
(SP_INTERFACE_DEVICE_DETAIL_DATA);

if (! SetupDiGetInterfaceDeviceDetail (
HardwareDeviceInfo,
DeviceInfoData,
functionClassDeviceData,
predictedLength,
&requiredLength,
NULL)) {
free( functionClassDeviceData );
return INVALID_HANDLE_VALUE;
}

strcpy( devName,functionClassDeviceData->DevicePath) ;

hOut = CreateFile (
functionClassDeviceData->DevicePath,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL, // no SECURITY_ATTRIBUTES structure
OPEN_EXISTING, // No special create flags
0, // No special attributes
NULL); // No template file

if (INVALID_HANDLE_VALUE == hOut) {

}
free( functionClassDeviceData );
return hOut;
}