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toh:netgear:dg834.v4

Netgear DG834G V4

WARNING: Do not confuse the DG834G v4 with versions v1,v2 DG834G, v3 DG834V3 or DG834GT!

Also note that the Wifi chip for this router is the Broadcom BCM4318 chip and not the atheros.

Router DG834GBv4 is interchangeable with this, but installation instructions does not apply because of differences in original OEM firmware.

Hardware Highlights

CPU Ram Flash Network USB Serial JTag
Broadcom bcm6348@240MHz 16MiB 4MiB 4 x 1 possible Yes Yes

NOTE:

  • There is NO support for the ADSL modem currently!
  • USB layout is unknown.

Installation

  1. Unpack it:
    1. unzip DG834GV4_V5.01.16_src.zip
    2. tar xvfj DG834GV4_V5.01.16_src.tar.bz2
  2. Get code for mkimage.sh file from post #424 on https://forum.openwrt.org/viewtopic.php?pid=89333#p89333

#!/bin/sh
 
       ###########################################################
       #### mkimage.sh put in directory DG834GV4_V5.01.16_src ####
       ###########################################################
 
       if [ "$1" = "" ] || [ "$2" = "" ] || [ "$3" = "" ]; then
         echo "Usage:" $0 "orignal_image openwrt-96348GW-10-squashfs-cfe.bin new_image"
         exit
       fi
 
       echo
       echo "Original Image:" $1
       echo "bcm963xx_fs_kernel:" $2
       echo "New Image:" $3
       echo
       echo "Press 'y' to continue"
 
       read yn
 
       if [ "$yn" = "y" ]; then
               tools/makeImage $3 $1 $2
               echo $3 "Created!"
       else
               echo "EXIT!"
       fi

  1. Now generate the .img for upgrading through the OEM web interface. We will use the script mkimage.sh in this way:
  • Copy mkimage.sh to the directory DG834GV4_V5.01.16_src.
  • Download latest OpenWRT and copy it in directory DG834GV4_V5.01.16_src.
  • ./mkimage.sh DG834GV4_V5.01.16.img openwrt-DG834GT_DG834PN-squashfs-cfe.bin miOpenWrt_DG834Gv4.img
 NOTE: The script 'mkimage.sh' retrieve from original firmware (DG834GV4_V5.01.16.img) 
       65536 bytes for the bootloader or CFE and added to the beginning of the OpenWrt firmware.

Preparring the router to upload the firmware:

  • Power down DG834Gv4 and disconnect the DC plug from the rear of the unit.
  • Wait 5-10 seconds.
  • Switch on the DC adapter at the mains switch.
  • With the reset button pressed, plug the DC adapter plug into the rear of the DG834Gv4.
  • Wait 5-10 seconds and not release the reset button.
  • The power button starts to blink green and red alternatively.

If we have linux installed:

  1. Compile NFTP utility:nftp.c (more info in: http://wilmer.gaa.st/834root/wiki/nftp)
  2. ./nftp -u eth0 miOpenWrt_DG834Gv4.img

If we only have windows installed, the procedure is as follows:

 Note: dg834_recovery_utility.zip only works on windows 32bit

Flash Layout

Please check out the article Flash Layout. It contains an example and a couple of explanations.

Partition Size EraseSize Name Function
mtd0 00010000 00002000 "CFE" bootloader
mtd1 000dff00 00010000 "kernel" kernel
mtd2 00300000 00010000 "rootfs" root file system
mtd3 000b0000 00010000 "rootfs_data" conf, packages
mtd4 00010000 00010000 "nvram" OEM conf
mtd5 003e0000 00010000 "linux" upgrade

OEM easy installation

FIXME The instructions below are for Broadcom devices and only serve as an example. Don't leave them in place if they do not apply to a particular device!

This section deals with how you install OpenWrt from a device freshly opened. Plus the steps required such as reset to factory defaults if the device has already been configured

Note: Reset router to factory defaults if it has been previously configured.

OEM installation using the TFTP method

If you want to upgrade using TFTP you follow these steps (as an alternative to the above install process).

Upgrading OpenWrt

generic.sysupgrade

If you have already installed OpenWrt and like to reflash for e.g. upgrading to a new OpenWrt version you can upgrade using the mtd command line tool. It is important that you put the firmware image into the ramdisk (/tmp) before you start flashing.

LuCI Web Upgrade Process

Terminal Upgrade Process

  • Login as root via SSH on 192.168.1.1
  • Use the following commands to upgrade.

cd /tmp/
wget http://downloads.openwrt.org/snapshots/trunk/XXX/xxx.abc
sysupgrade /tmp/xxx.abc

  • If sysupgrade does not support this router, use the following commands.

cd /tmp/
wget http://downloads.openwrt.org/snapshots/trunk/XXX/xxx.abc
mtd write /tmp/xxx.abc linux && reboot

Basic configuration

Basic configuration After flashing, proceed with this.
Set up your Internet connection, configure wireless, configure USB port, etc.

Specific Configuration

Interfaces

The default network configuration is:

Interface Name Description Default configuration
br-lan LAN & WiFi 192.168.1.1/24
vlan0 (eth0.0) LAN ports (1 to 4) None
vlan1 (eth0.1) WAN port DHCP
wl0 WiFi Disabled

FIXME

Switch Ports (for VLANs)

Numbers 0-3 are Ports 1-4 as labeled on the unit, number 4 is the Internet (WAN) on the unit, 5 is the internal connection to the router itself. Don't be fooled: Port 1 on the unit is number 3 when configuring VLANs. vlan0 = eth0.0, vlan1 = eth0.1 and so on.

Port Switch port
LAN 1 3
LAN 2 2
LAN 3 1
LAN 4 0

FIXME

Failsafe mode

GPIOs

GPIO line Connected
0 Green LED Power
1 Red LED Power
2 LED Dsl
3 LED Internet

Buttons

hardware.button on howto use and configure the hardware button(s).

The Netgear DG834G V4 has only one button:

BUTTON Event GPIO
Reset reset 6

Hardware

Info

Architecture: MIPS
Vendor: Broadcom
Bootloader: CFE
System-On-Chip: BCM6348SKFBG
CPU/Speed BMIPS3300 V0.7 / 240 MHz
Flash-Chip: Spansion S29GL032A90TFIR4
Flash size: 4 MiB
RAM: EM638165TS-6G / 16 MiB / 166MHz
Wireless: Broadcom 4318 11b/g
Ethernet: BCM5325 w/ vlan support swconfig
Internet: ADSL2+
USB: possible 1 x 1.1
Serial: Yes
JTAG: Yes

Photos

Model Number

Photo of front of the casing

Photo of back of the casing

Opening the case

Note: This will void your warranty!

Main photo of PCB

Back photo of PCB

Serial

port.serial general information about the serial port, serial port cable, etc.

Serial console is J521. Settings are: 115200, 8, n, 1

How to connect to the Serial Port of this specific device:

NOTE: R521, R522 and R523 are missing on the DG834Gv4, (it could be 1 kiloohm).

Pint out Line
1 GND
2 Tx
3 Vcc
4 Rx

Photo of PCB and resistors unpopulated:

JTAG

port.jtag general information about the JTAG port, JTAG cable, etc.

How to connect to the JTAG Port of this specific device:

Netgear DG834 comes with standard 12-pin JTAG interface. The JTAG port is J201.

Name signal Pint out Pin out Name signal
nTRST 1 2 GND
TDI 3 4 GND
TDO 5 6 GND
TMS 7 8 GND
TCK 9 10 GND
nSRST 11 12 n/a

Example of use:

JTAG XILIX Parallel Port
11 nSRST
9 TCK———100R———D1, Pin 3
7 TMS——–100R———D2, Pin 4
5 TDO——–100R———Select, Pin 13
3 TDI———100R———D0, Pin 2
1 nTRST
2 GND————————————— GND, Pines 20, 25

Photo of PCB with connector

Debricking

Bootloader Mods

  1. you could read about bootloader in general

Hardware mods

  1. as a beginner, you really should inform yourself about soldering in general and then obtain some practical experience!

128MiB RAM Mod

I²C GPIO Mod

I²C Tiny-USB Mod

Notes

Tags

For some Help with the Tags, please have a look here: tags

toh/netgear/dg834.v4.txt · Last modified: 2013/04/21 01:42 by pinky