Need some help here. My Hikvision DS-7608N-E2 8P has gone into 15 beeps and then reboot itself after firmware upgrade. I can ping both 22.214.171.124 and 126.96.36.199 but I'm not able to see NVR taking the file. Is there a special cable to connect to the board, like a usb to pin? If so, you what type of cable is that? Thanks.