public static extern int IP_NET_DVR_SerialStart(int lUserId, fSerialDataCallBack cbSDCallBack, IntPtr pUser);
private static extern Int32 IntNET_DVR_SerialStart(Int32 lUserID, Int32 lSerialPort, fSerialDataCallBack fSerialData, int dwUser);
public static extern int IP_NET_DVR_SerialStart(int lUserId, fSerialDataCallBack cbSDCallBack, IntPtr pUser);
private static extern Int32 IntNET_DVR_SerialStart(Int32 lUserID, Int32 lSerialPort, fSerialDataCallBack fSerialData, int dwUser);