Which JST ZH Header ?

[IceK]

I have a 16 channel DVR that has is not showing user name for login and I presume that it has bad firmware flashed.
From the information I have found I can reflash it using a USB TTL cable, however the board has two JST ZH headers and I don't know which one is the correct one to connect the Ground, RX & TX cables to.

 

[alastairstevenson]

The answer may depend on knowing the brand and model of the (unspecified) DVR.

 

[IceK]

The answer may depend on knowing the brand and model of the (unspecified) DVR.

Its a Hikvision Ds-7216HQHI-K2. I managed to get the header and the UART is working, but my prompt is HKVS $ and its not accepting any input.
I have tried

setenv ipaddr 192.0.0.64
setenv serverip 192.0.0.128
setenv bootargs console=ttyS0,115200n8 root=/dev/ram0 rw initrd=0x42000000 init=/bin/sh
setenv bootcmd 'tftp 0x42000000 uImage; update'

and its timing out, with the error below


Download Filename 'digicap.dav'.
Download to address: 0x43000000
Downloading: T T T T T T T T T T T T T T T T T T T T
Retry count exceeded; starting again

 

[alastairstevenson]

Check the ipaddr and serverip addresses to see if they match your network and PC.

 

[IceK]

Resolved it, by having TFTP server running and then restarting the upgrade.
If you don't have the server running then you get "Downloading: T T T T T T T T T T T T T T T T T T T T " on screen, with the server running the Ts change to # and the DVR gets the upgrade file.
The header for the UART TTL cconnection is on the right of the SATA power connector, just below the Power LED.
There is a second JST ZH header on the far right near JP17 behind the BNC connections, which is not used for our TTL cable.
Thanks to Alastair and this forum for the valuable information to get my DVR running..

 

[IceK]

Check the ipaddr and serverip addresses to see if they match your network and PC.

The addresses were correct, problem was the TFTP server not running in the background