USB传输速度问题，怎样提速？？？？？？

panwen516 2011-05-05 10:07:37

使用WDM架构：
驱动层代码如下：
NTSTATUS Write_Dirc_TestDevice::Write(KIrp I)
{

T.Trace(TraceInfo, __FUNCTION__"++. IRP %p\n", I);

NTSTATUS status = STATUS_SUCCESS;

// TODO: Validate the parameters of the IRP. Replace "FALSE"
// in the following line with error checking code that
// evaulates to TRUE if the request is not valid.
if (FALSE)
{
status = STATUS_INVALID_PARAMETER;
I.Information() = 0;
I.PnpComplete(status);

T.Trace(TraceWarning, __FUNCTION__"--. IRP %p, STATUS %x\n", I, status);

return status;
}

// Always ok to write 0 elements
if (I.WriteSize() == 0)
{
I.Information() = 0;
I.PnpComplete(this, status);

T.Trace(TraceInfo, __FUNCTION__"--. IRP %p, STATUS %x\n", I, status);

return status;
}

KMemory Mem(I.Mdl()); // Declare a memory object

// Get a pointer to the caller's buffer. Note that this
// routine is safe on all platforms.
PUCHAR pBuffer = (PUCHAR) Mem.MapToSystemSpace();
ULONG writeSize = I.WriteSize();
ULONG bytesSent = 0;
// TODO: At this point, perform any processing for IRP_MJ_WRITE
// To satisfy the write now, transfer data to the driver
// from the caller's buffer at "pBuffer". Then, indicate
// how much data was transferred:

PURB pUrb = Pipe3.BuildBulkTransfer(//写端点
pBuffer,
writeSize,
FALSE,
NULL,
TRUE,
NULL);
if (pUrb == NULL)
{
status = STATUS_INSUFFICIENT_RESOURCES;
}
else
{
status = Pipe3.SubmitUrb(pUrb,NULL,NULL,NULL);
bytesSent = pUrb->UrbBulkOrInterruptTransfer.TransferBufferLength;//pUrb->UrbInterruptTransfer.TransferBufferLength;
delete pUrb;
}

I.Information() = bytesSent;

I.PnpComplete(this, status);

T.Trace(TraceInfo, __FUNCTION__"--. IRP %p, STATUS %x\n", I, status);

return status;
}
-----------------------------------------------------------------------------------------------
应用层调用代码：
BOOL bResult;
DWORD nBytesWritten;
OVERLAPPED gOverlapped;
DWORD dwResult;

dwResult = MPUSB_FAIL;
gOverlapped.Internal = 0;
gOverlapped.InternalHigh = 0;
gOverlapped.Offset = 0;
gOverlapped.OffsetHigh = 0;
gOverlapped.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

uint8 data[1] = {0xE6};
WriteFile(pCurrentDevice,data,1,&nBytesWritten,&gOverlapped);

------------------------------------------------------------------------------
通过硬件设备监控，应用层代码循环调用多次，每次发送与上次发送（WriteFile）间隔都是2ms。
问题是，我每次只传输一个字节呀。。怎么提高速度，太慢了？
USB是全速的，使用的是bulk传输方式，XP系统。USB2.0

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