public static extern Boolean DeviceIoControl(
[In] IntPtr handle,
[In] Int32 dwIoControlCode,
ref HPTimerHWtruct timer, // [In] Byte[] lpInBuffer, //[In] IntPtr lpInBuffer,
[In] Int32 nInBufferSize,
[Out] Byte[] lpOutBuffer, //[Out] IntPtr lpOutBuffer,
[In] Int32 nOutBufferSize,
out Int32 lpBytesReturned,
[In] IntPtr lpOverlapped);
static UInt32 GetTime()
{
UInt32 time;
unsafe
{
if (timerAddress == null)
{
IntPtr handle = IntPtr.Zero;
HPTimerHWtruct timerStruct;
try
{
handle = WindowsCESafeNativeMethods.CreateFile("TRC1:", GenericRead | GenericWrite, 0, IntPtr.Zero, OpenExisting, 0, IntPtr.Zero);
if (handle == IntPtr.Zero || handle == new IntPtr(-1))
{
throw new InvalidOperationException("CreateFile returned invalid handle");
}
timerStruct = new HPTimerHWtruct();
timerStruct.Revision = 1;
Int32 bytesReturned;
if (!DeviceIoControl(handle, MapTimerHw, ref timerStruct, 20, null, 0, out bytesReturned, IntPtr.Zero))
{
throw new InvalidOperationException("DeviceIoControl returned 0");
}
}
finally
{
if (handle != IntPtr.Zero && handle != new IntPtr(-1))
{
WindowsCESafeNativeMethods.CloseHandle(handle);
}
}
if (timerStruct.TimerRegPtr == IntPtr.Zero)
{
throw new InvalidOperationException("HPTimerHWStruct.TimerRegPtr is 0");
}
timerAddress = (UInt32 *)(timerStruct.TimerRegPtr);
}
time = *timerAddress;
}
return(time);
}