Hikvision - Clearing Passwords and/or Loading Firmware via TTL Serial

moped

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I recently picked up a used Hikvision DS-7608NI-E2/8P (at auction) that was password locked. The seller was unable to tell me where it was sold, and all the Hikvision offices I contacted (US, EU, AU, CN, HK) provided the canned "purchased through an unauthorized" channel response. The stated source of the hardware seemed to have no bearing on the response either (I bought local, I bought at auction, acquired through acquisition of another company, etc). I have another identical unit (also used) that was sold in the US and they assisted with a password reset, no questions asked, no information regarding where I purchased was asked either.

The password locked unit was shipped in retail packaging with serials that matched (box + device + SADP). The firmware installed appears to be US or ML (not hacked, not CN), but the serial seems a little odd. The other used (verified US) unit that I have has a serial number that starts with 6591xxxxx and has a canned verification code for Hik-connect on the label. The manufacture date of that unit is 2016. The password locked unit has a serial number that starts with 1351xxxxx and no precreated hik-connect code. Lower serial number, same exact model? The manufacture date of the password locked unit is less than six months ago - Nov 2017. The other odd thing is that the firmware on this new (password locked) unit was one build number newer than the latest version of the firmware posted (anywhere) for their I series NVRs.

I recently had a grey market DS-2CD2132 camera that I attempted to update the firmware, which lead to tftp recovery (which consequently removes the device configuration and password). The normal tftp recovery process (where it reaches out to 192.0.0.128) seems to have been removed from the most recent versions of Hik firmware though... So I started looking for something similar to the serial recovery that I had seen on some camera posts. I did find a few posts with folks attempting the same thing on an NVR (with mixed success) but the only posts with any real details at all were related to cameras.

I'm a firm believer in the right to repair. I have huge issues with Hikvision's password reset policy / distribution polices. I understand their viewpoint / concerns about products not sold through authorized channels and could even agree with not providing support to these units, but what they have done is quite different. Not only will they not support you with your unauthorized product, but they have injected themselves into the most basic support item (password resets) which lets them force these units out of service early. They have continually worked to lock their products down as well, so even with physical access, you may just end up with a paperweight (and no way to really tell if this will be the case before buying). None of this seems to be in the interest of their customers. It all seems to be borne out of their desire to control/protect regional pricing (vs using a global pricing model) and their inability to control what their distributors/resellers are doing. So they lock things down and make it more difficult for end users. If I didn't know what I was getting into and as a hobbyist had dropped several hundred on what I thought was a DIY system and they told me to go kick rocks when I asked for a password reset, I probably would blame the source of my purchase a lot less than I blame the manufacturer of the product (with the insane policies).

So outside of sticking it to Hikvision, the main purpose of this post is to put all the information regarding Serial TTL recovery in one place, so that the next guy doesn't have to jump through quite as many hoops as I did. The cable and basic steps here are identical for Hikvision cameras (although some disassembly is usually required to get to the connector on the camera).

The first thing to note is that most of the time when serial recovery is referred to with Hikvision, it's referring to TTL serial. There are some NVRs that support RS232 connections, but you can usually tie into these on the back (without opening it up) through the terminal block and/or a dedicated serial port. A TTL Serial to USB cable can be purchased for $3-10 from various online sources. On one end you will see a USB connection, and the other will have 3-4 wires. You can read about the differences between TTL Serial and RS232 ("normal" serial) here: RS-232 vs. TTL Serial Communication - SparkFun Electronics


Supplies
  • TTL Serial Adapter ($5-15)
  • Ethernet cable
  • Four pin JST ZH cable (1.5mm pins) (Amazon, eBay, etc)
  • Windows laptop/desktop
  • Latest (or deisred version) firmware for NVR
  • PuTTY (terminal software) - link within instructions
  • tftpd32 (to send firmware to NVR) - link within instructions


You should be looking for a four pin JST ZH header on the mainboard, that looks like this:


Here it is on a camera board:


An older Analog NVR:


A DS-7604:


A DS-7608:



You may see more than one JST connector. If you do, you may need a multitester to determine the pinout, or to see if it's actually a TTL serial connection. It's fairly easy -- one outer pin should be hot, the other should be a ground. Ground is pin #1, hot is pin #4. On my unit, pin #1 (ground) had a white arrow printed on the PCB next to it. If you don't read anything from these two pins with the unit powered on, it's probably a safe bet that it's not a TTL serial port.

After finding your port you will need to get (or fabricate) a four pin JST ZH cable. The pins are 1.5mm apart. Best bet is to purchase a pre-made cable (easily sourced online):



This is a common connector (used with some LiPO cells) so I actually had a bag of two pin headers+connectors laying around. I opted to fabricate, since I didn't want to wait for the proper cables to ship. If you have two pin headers, you can simply file down one side of each so that you can get both in the four pin socket.


You'll also need that TTL Serial adapter:


Please note, the first two sections here simply tell you what the pinouts are for each side (JST And TTL Cable). These are for reference only and do not reflect how you should actually connect things up (see below the rx/tx diagram for this info). Power should be turned off (via power supply switch or cable pulled) while you are tinkering around inside.

TTL Serial Cable Pinout
Red = 5v
Black = Ground
White = RX (into USB)
Green = TX (out of USB)

JST Pinout
Pin 1 = Ground
Pin 2 = TX (out of NVR)
Pin 3 = RX (into NVR)
Pin 4 = 3.3v

When connecting, RX goes to TX as shown here:


How to connect your cable:
JST Pin 1 -> TTL Ground (black)
JST Pin 2 -> TTL RX (white)
JST Pin 3 -> TTL TX (green)
JST Pin 4 -> NO CONNECTION

IMPORTANT: THE RED (+5V) LEAD SHOULD NOT BE CONNECTED TO JST PIN 4. YOU ONLY NEED THE TX/RX/GROUND CONNECTIONS TO MAKE THIS WORK. YOU COULD POTENTIALLY DAMAGE THE UNIT IF YOU CONNECT THE RED(+) LEAD!

Here is my ghetto cable installed w/TTL Serial adapter connected. Note that the fourth pin has no connection (it's not touching the power supply in the pic either - just an angle issue with the photo):



After you are done wiring things up, you will need to connect the USB side of the TTL Serial adapter. You may need to install drivers from the manufacturers site. I did not have good luck when trying to pass one of these adapters through VMware Fusion to a Windows 10 VM. I ended up breaking out an old Windows 7 laptop in the end.

My adapter (the one shown in this pic) uses a PL2303 chip. You can get the latest drivers here:
Products

You will need to download PuTTY (or a terminal emulator of your choice that supports serial):
Download PuTTY - a free SSH and telnet client for Windows

You will need a plain TFTP server (not the one from Hikvision). I recommend using the portable version of tftpd32 (free). Extract to a subfolder of your downloads folder and run it from there:
TFTP server

You will also need an ethernet cable (crossover not required) to get the firmware (firmware is not transferred through the serial connection).

Your ethernet cable can be connected in one of two ways:
  1. Directly from NVR to the Laptop/Desktop that you are using
  2. From NVR to the same network segment (same vlan/subnet) that the Desktop/Laptop is on
If you go with #2, remember that you won't be able to set a subnet or gateway on the NVR. When the time comes to load firmware, you will be prompted for server and client IP only. This is why it's important that it's on the same network segment as the machine that will host TFTP.

If you go with #1 (which was easiest for me), you will need to manually set the IP address on the computer. Network adapter settings, right click the network adapter, double click TCP/IP V4, enter as shown below:



Now you need to figure out what COM port that the TTL Serial adapter has been assigned to. Open Device Manager in Windows, click the > by "Ports (COM & LPT)" and you should see COM#. If you see more than one COM port listed and you aren't sure which to use, note the COM port numbers used - you may have to test each one with PuTTY as the NVR boots to figure out which is the correct one to use (trial and error).

After you have the COM Port(s) information, open up PuTTY. On the first screen you see, select "Serial" for Connection type, manually type your port under Serial line. My adapter came up on COM6 (shown below). Speed should be set to 115200:


Click on serial (bottom of the list on the left), make sure the Serial line to connect to matches what you entered on the first screen, as well as the speed. Data bits 8, Stop bits 1, Parity None (these should be the default settings). Change flow control to none/off (not a default setting!).


Once complete, click Open, then power on your NVR. If you have the correct port selected, you should see something like this when it powers on:



Let's move on to setting up the TFTP server. I'm only providing instructions for tftpd32, but the setup should be similar with other tftp server software. When you initially open tftpd32 you may see some firewall prompts etc. Adding exceptions is fine, but if your NVR and the TFTP server don't seem to be communicating, you may want to disable windows firewall as a first step when troubleshooting. Once tftpd32 is open, click the settings button at the bottom. Click the global tab, uncheck DHCP server. Click the TFTP tab and select "None" for TFTP security. Click OK, it will tell you you have to restart the app, click OK, close the app, reopen.

Now you need to download firmware from Hikvision. I had a US model, so I used the US firmware. I actually loaded a version that was one release number behind the version that was installed. I had zero issues but your mileage may vary here. If you choose the wrong firmware (and don't have a grey market model with hacked firmware) it will do the usual checksum/region mismatch and won't install the firmware file. Download the latest firmware release for the NVR and extract the zip file. The digicap.dav file inside the zip needs to be copied into the root folder of tftpd32 (this is why I recommend the portable version - configure + drop the file in the same folder).

At this point you should have the TTL Serial cable all set, the COM port verified, PuTTY setup, tftpd32 setup and running with the firmware that you want to install to the device residing inside the tftpd32 folder.

From here:
  1. Power on NVR
  2. Press CTRL-U to interrupt boot process

  3. Press u (to upgrade software)
  4. IP of device (NVR)
    1. If you direct connected to the computer you can use 192.0.0.64 as the IP
    2. If you connected to your existing LAN, you need to enter an unused IP on the same subnet as the machine that is hosting tftp services
  5. IP of server (Laptop/Desktop with tftpd running) - mine was set to 192.0.0.128
  6. Press y to confirm (then press enter)
  7. From here it should download + install the firmware file
  8. At the end of the installation it will say "Press ENTER to reboot" -- press enter
Terminal log (what you can expect to see):



Firmware should be loaded and all configuration (including password) should be cleared. All cables can be removed and the NVR can be setup/moved/etc. It will be in an unactivated/inactive state with no password set at all. The first screen that you see at startup (if you connect it via HDMI) should be to set the password:
 
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tangent

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Nice write up, but I cry a little on the inside when people take screenshots of their computers with a digital camera. Next time try your print screen button or the windows snipping tool. Pro tip: Alt-print screen captures the current window only.

There are some other threads here on Hik tftp and password resets.
 

alastairstevenson

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the main purpose of this post is to put all the information regarding Serial TTL recovery in one place, so that the next guy doesn't have to jump through quite as many hoops as I did.
Well, that's a terrific post for a thread starter. Kudos for the level of detail, clarity and effort that's gone into it.
The thread could very well turn into a valuable reference source that many people could get some benefit from.
So, if I may, I'd like to maybe add a few more items that could be useful.

By the way - I do agree generally with your sentiments about Hikvision's practice of trying to punish those customers who have purchased on-line at much lower cost than if it had been via an 'authorised' source. That's one reason why I've been so keen to help out those whose cameras have 'bricked' when doing what should come naturally - a firmware update for bugfixes, security fixes and functionality.

Firstly - in terms of a lost password, the tftp update of nominally the same firmware that's installed is certainly one approach.
But I'd caution people trying this to somehow find out if their NVR is a China market model running 'hacked to English' firmware. This would generally be those NVRs with the -N model suffix as opposed to the -NI suffix.
An update with stock firmware for those models will likely result in a bricked NVR having the " !!! You device is illegal !!! !!! You bought in China !!! ....." 15-beep bootloop.
So be careful.

The serial console is a powerful way to access the internals of an embedded Linux device, and particularly so on Hikvision devices, when they have been designed with deliberate traps and blocks to stop people doing what they think they should be able to on the products that they have purchased.

Despite these obstacles, there are enough clever people around who have the inquisitiveness and ability to explore them and work round them, so in reality it's a fairly pointless tactic, given the power of internet search these days.
It's not hard to see that Hikvision do take note of any openly-published 'tweaks' and incorporate measures against them in new firmware releases.
So I was going to describe here a really simple way to gain very good access to Hikvision NVR internals - but find that I'm having second thoughts about doing so.
Whilst it may be that the firmware for the DS-76xxNI/E series has probably reached end-of-life, this trick works even better on later models where the firmware is still being worked on and where there is a r/w file system instead of the previous CRAMFS r/o file system.
 

tangent

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By the way - I do agree generally with your sentiments about Hikvision's practice of trying to punish those customers who have purchased on-line at much lower cost than if it had been via an 'authorised' source. That's one reason why I've been so keen to help out those whose cameras have 'bricked' when doing what should come naturally - a firmware update for bugfixes, security fixes and functionality.
It ultimately hurts them in the long run because some of the customers who might roll the dice on a cheap Chinese model and get burned are also in positions to influence purchasing decisions at large corporations.
 

jcc

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It ultimately hurts them in the long run because some of the customers who might roll the dice on a cheap Chinese model and get burned are also in positions to influence purchasing decisions at large corporations.
I'm in awe about how much you guys know about this shit/stuff!!!Congratulations and God bless..
 

moped

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It ultimately hurts them in the long run because some of the customers who might roll the dice on a cheap Chinese model and get burned are also in positions to influence purchasing decisions at large corporations.
As with most of my projects/hobbies, my tinkering and personal purchase of Hik products was borne out of a business need. I manage a couple of IT groups at a large (global) aerospace company with several facilities that are "on-runway" at international airports. My guys are responsible for all physical hardware + standards (everything except tooling) - the CIO and I are the IT/security decision makers. Currently we are using Honeywell + Axis (security cams as well as access control products). If I wanted to pay the Honeywell tax (which also forces you to use a local installer vs DIY), I would stick with Honeywell/Axis. Fall/winter project time is virtually over, but hoping to pick up some Dahua product to play with later this year. Hikvision is a non-starter due to my less than stellar experience with their products/support.

I'll update the original post this week so that it's structured a little better - list of materials, little more organized, etc. Intended to update this weekend but I didn't have time.
 

tangent

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As with most of my projects/hobbies, my tinkering and personal purchase of Hik products was borne out of a business need. I manage a couple of IT groups at a large (global) aerospace company with several facilities that are "on-runway" at international airports. My guys are responsible for all physical hardware + standards (everything except tooling) - the CIO and I are the IT/security decision makers. Currently we are using Honeywell + Axis (security cams as well as access control products). If I wanted to pay the Honeywell tax (which also forces you to use a local installer vs DIY), I would stick with Honeywell/Axis. Fall/winter project time is virtually over, but hoping to pick up some Dahua product to play with later this year. Hikvision is a non-starter due to my less than stellar experience with their products/support.

I'll update the original post this week so that it's structured a little better - list of materials, little more organized, etc. Intended to update this weekend but I didn't have time.
Hikvision makes "Honeywell" cameras.
Hikvision OEM Directory
 

moped

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Hikvision makes "Honeywell" cameras.
Hikvision OEM Directory
Primarily using Axis right now (some units here are strictly military work - no CN cameras or IoT devices there, airgapped networks, etc). Honeywell is used for access control and HVAC controls, primarily.

Honeywell also rebrands some Dahua + other manuf's cams. I like to use Honeywell as a whipping boy for price inflation/market control sometimes - they add a premium for affixing their label on the outside and you get a network of inexperienced installers/techs to help screw things up. Honeywell Prowatch is a splendid example - getting the hardware installed is no big deal, but getting someone who knows how to configure the hardware (or Prowatch itself!) is an entirely different story. Local or national installers, east coast, west coast, midwest - all similar experiences (always seem to be paying someone to learn).
 

greg63

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Hi,
I think I've followed the process but I find myself blocked at the end of step 2. Icannot reach step 3.
I precise I work on DS-7216HUHI-K2

Can somebody help me, please?

 

moped

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Hi,
I think I've followed the process but I find myself blocked at the end of step 2. Icannot reach step 3.
I precise I work on DS-7216HUHI-K2
Can somebody help me, please?
It looks like you've dropped to a busybox shell, note the onscreen instruction:
"Enter 'help' for a list of davinci system commands"


Doing this will list all commands...
HKVS # help
? - alias for 'help'
bootd - boot default, i.e., run 'bootcmd'
bootm - boot application image from memory
cmp - memory compare
cp - memory copy
crc32 - checksum calculation
format - format nand except bootloader area
fsinfo - print information about filesystems
fsload - load binary file from a filesystem image
go - start application at address 'addr'
help - print online help
ls - list files in a directory (default /)
md - memory display
mm - memory modify (auto-incrementing)
mtest - simple RAM test
mw - memory write (fill)
nand - NAND sub-system
nboot - boot from NAND device
ping - send ICMP ECHO_REQUEST to network host
pready - set panel to ready
printenv- print environment variables
reset - Perform RESET of the CPU
saveenv - save environment variables to persistent storage
setenv - set environment variables
tftpboot- boot image via network using TFTP protocol
update - update digicap.dav
updateb - update uboot(u-boot.bin) to nor
updatebl- update ubl(ubl_646x.bin) to nand
updatefs- update filesystem(davinci.img) to nand
updatek - update kernel(uImage) to nand
updates - serial update kernel or filesys

Update is the command you are looking for -- just type: update and press enter (then follow onscreen instructions)
 

greg63

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Support Commands:
GetAnrCfgInfo GetAnrProcess GetAnrRecordList
ShowIpcAbility accessDvrSwitch channelPlayback
clearDisksMode ctrlArchDebug decStat
disableHB disableHik264 dspStatus
dvrLogInfo dt enableHB
enableHik264 enableWatchdog errputClose
errputOpen get3GMode getCMS
getCycleReboot getDbgCtrl getHardInfo
getIp getLastErrorInfo getPlayTestCtrl
getPort getServerInfo guiChkCfg
guiEnterMenuCount guiPrtScr guiStatus
helpm helpu i2cRead
megaDspConfig miscCmd netstat
outputClose outputOpen partRecDetails
ping printPart pthreadInfo
recorderChanInfo recorderFileInfo recorderFileKeyFrame
recorderHDIdle recorderMediaInfo recorderPAllocFile
recorderParam recorderSegExtraInfo recorderStatus
sendATCom set3GPrint set3GEnable
searchInfo setGateway setIp
setlang setMtu setoutputmode
setPrint show8107coreUseInfo showCurPlayChanFileInfo
showDeviceTemp showIpcMemInfo showNetIpcmInfo
showNetLinksInfo showPlayChanStatus showPlayClipFile
showPlayScreenInfo showPlayStatus showPlayTime
showPreviewInfo showShareSvcInfo showSpareWorkStatus
showTagSysInfo showUserInfo showpu
t1 t2 transcodeResStatus
getDateInfo dmesg help
 

greg63

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Commands Usage

helpm : Printf the command usage list
getIp : Get the device's IP address
setIp : Set the device's IP address
Usage: setIp [IP ADDRESS]:[SUBNET MASK]
e.g. setIp 192.168.1.10:255.255.255.0
getPort : Get the device's command PORT
setPort : Set the device's command PORT
Usage: setPort [PORT NUMBER]
e.g. setPort 8000
getGateway: Get the device's gateway
setGateway: Set the device's gateway
Usage: setGateway [GATEWAY ADDRESS]
e.g. setGateway 192.168.1.1
getNetInterface: Get the net interface name
Usage: getNetInterface [NEEDLOCALBACK]
NEEDLOCALBACK: need localback or not 0 for not need,1 for need
getNetstatus : Get the device netstatus
Usage: getNetstatus [ NETTYPE ]:[ IPVER ]:[ CHECKOPT ]
NETTYPE: use getNetInterface to obtain
IPVER:0 or 1 ,0 for IPV4,1 for IPV6
CHECKOPT: 1 or 2 or 3,1 for check linklayer 2 for check IPlayer,3 for check all layer
e.g. getNetstatus eth0:1:2
getARPtable : Get the ARPtable item
showRoutetoHost: Show the route to host
Usage: showRoutetoHost [ HOST ]:[ HOPMAX ]
HOST: Host Nmae
HOPMAX: The max hop number
eg. www.google.com:30
startPCAP : Capture the packet & display the key information
Usage: startPCAP [ IFNAME ]:[ FILENAME ]
IFNAME: the interface name,use getNetInterface to obtain
FILENAME: the file to save pcap format data
e.g. startPCAP eth0:/mnt/msb1
getInetTraffic : Get the net traffic status of latest 10s
Usage: getInetTraffic [ IFNAME ]
IFNAME: the interface name,use getNetInterface to obtain
e.g. getInetTraffic eth0
ShowIpcAbility: Get and Show the Ipc Abilitity Info
Usage:ShowIpcAbility [Chan] Show Speified Chan Ability
e.g. ShowIpcAbility 1
NVRTestStart : Start NVR playback test for product
Usage: NVRTest [ CHAN ]:[ CHAN ] ...[ CHAN ]
CHAN: the chan you want to playback,support max 32 chan
e.g. NVRTest 1:2:6:5
NVRTestEnd : End NVR playback test for product
dspStatus: print DSP status info with format: dspStatus(arg1 arg2).
guiStatus: print GUI status info with format: guiStatus(arg1 arg2).
guiEnterMenuCount: print GUI menu count info with format: guiEnterMenuCount(arg1).
showTagSysInfo: print tag system info
Usage: showTagSysInfo partname fileNo segNo
getDbgCtrl: get debug ctrl param.
setDbgCtrl: set debug ctrl param with format: setDbgCtrl( password,iDbgLevel=0x?,iDbgFormat=0x?,iDbgModule=0x?,iDbgMask=0x?).
setMtu: Set the device's mtu, shall and current NIC type match
Usage: setMtu [NICTYPE] [VALUE]
e.g. setMtu bond0 1500
i2cWrite e.g i2cWrite 0x0 0x11 0xff
i2cRead e.g i2cRead 0x0 0x11
setlang e.g setlang 1
setoutputmode e.g setoutputmode 1
 

greg63

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Thanks for you answer.
When I use control-U, right at the beginning it stops the bootloader but then the commands don't work anymore: I have no more answer.
 

alastairstevenson

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Going back to basics - what are you trying to achieve?
What's the status of the NVR, and how did it get that way?

By the way - check out the PuTTY 'copy screen rollback to clipboard' facilities via the menu at the top left of the window - easier than taking screenshots.
 

moped

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try pressing tab a couple of times and see if there is any output.. if that doesn't work, type 'ls' and press enter and see if there is any output from that.
 

greg63

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The dvr (DS-7216HUHI-K2) was wrongly updated from 3.5.35 version to 3.5.50 version.
Since then, it is impossible to establish a connexion.
The admin login doesn’t exist anymore and the storage is not visible anymore from the SADP.
I’m trying to come back to the original firmware.


MOPED, thanks for your answer. I also tried your solution but it didn't work.
 

m-blue

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I have the same... dvr - DS-7208HUHI-K2 , after firmware upgrade no user to choose, so can't login. SADP don't see it, but there is answer to ping via pc... I am tryging fix it second week in free time...
I can connect via putty, but there is no response to keyboard , can't stop booting via ctr+U, and can't put any command after dvr is up. I was looking for putty settings, because I am not only one with this problem ( no keybord response in putty) but I hope that somebody will help here :) It looks similary to Gregs53 problem. thx
 

alastairstevenson

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can't stop booting via ctr+U,
Check that the TX from the serial TTL to USB convertor is properly connected to the correct pin on the DVR.
Check that if you just join TX and RX together on the serial TTL to USB convertor that characters you type get echoed.
 
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