SetDateTime()

[DllImport("RGUSBdrv.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern byte SetDateTime(uint DateTimeUNIX);

private void btnSetDateTime_Click(object sender, EventArgs e)
     {
      uint unixTimestamp;
      unixTimestamp = (UInt32)(DateTime.Now - new DateTime(1970, 1, 1, 0, 0, 0)).TotalSeconds;
      if (Connected)
      SetDateTime(unixTimestamp);
     }