NOTE: The FCC documentation is available here

→Flash Layout has an example flash layout and all explanations required to understand this. Here the naked hex-values for the WZR-HP-AG300H:

The easiest way to install OpenWrt is by using the firmware utility of the OEM web interface:

1. Connect to the WebInterface at http://192.168.11.1 and go to "Administration" → "Firmware Upgrade"
2. Upload the OpenWrt-Image you want to install, e.g. http://downloads.openwrt.org/attitude_adjustment/12.09-beta/ar71xx/generic/openwrt-ar71xx-generic-wzr-hp-ag300h-squashfs-factory.bin
3. Make your PC obtain a new IP address from OpenWrt (dhclient eth0 or pump -i eth0 or ipconfig /renew)
4. proceed with basic.config to complete installation

→ generic.flashing.tftp

Here is a link to the console output of the boot process, with all led's in view for reference http://www.youtube.com/watch?v=mAZNTKhpHig

• The red "DIAG"-LED begins to flash rapidly when the router has received the image and is currently booting the new firmware.
• Successful flashes via tftp using Windows 7 directly plugged into the router have been done. It helps to add arp entries and disable media sensing as per the generic tftp instructions.
• Flash should have reset all settings as well. The IP address of the router should be 192.168.1.1 now since 192.168.11.1 is only for the bootloader at boot-time
• If your router has two red flashes of the DIAG LED followed by no flash and repeats then the flash failed or the image given is corrupt. Start over and try again.

There are apparently several regional versions of the OEM firmware. You may have to adjust the region in u-boot first. Below is example of a succesful region change and flash procedure. Source: forum article

This is how to do it from serial console:

1. Hold the STRG+C pressed while poweron the Router.
2. After prompt apears do:
   • setenv accept_open_rt_fmt 1
   • setenv region EU
   • saveenv
   • reset
   • (it reboots now)
3. After Reboot Power your Device down!
4. Set Your LAN IP to 192.168.11.2
5. In a linux terminal use these commands
   • wget -O myfirmware.bin "http://downloads.openwrt.org/snapshots/trunk/ar71xx/openwrt-ar71xx-generic-wzr-hp-ag300h-squashfs-factory.bin"
   • sudo ip neigh add 192.168.11.1 dev eth0 lladdr 02:aa:bb:cc:dd:20 nud permanent <enter>
   • tftp 192.168.11.1 <enter>
   • verbose <enter>
   • bin <enter>
   • <powerup your device and wait 5 seconds>
   • put myfirmware.bin <enter>
6. In Windows cmd put that Line:
   • arp -s 192.168.11.1 02-AA-BB-CC-DD-20
   • tftp -i 192.168.11.1 PUT wzrhpag300h-pro-v24sp2-19154.enc (don't hit enter, yet)
7. Power on the Device and 10 Seconds after that hit enter in Windows CMD to start the TFTP. (it tooks about ten Minutes to Complete the flash procedure)

→ generic.sysupgrade

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

→ generic.failsafe

If you want to trigger a LED as soon as an USB-Device is connected to your USB-Port, add this to /etc/config/system:

This switches on the little red circle of the DIAG-LED everytime you connect something to your USB-Port.

• It's very unlikely that you completely bricked the device, so first try the TFTP Method above. Note that a red diagnostics light blinking twice means your flash failed, but the device is ok and tftp will work (keep trying). If you still get nowhere, more drastic measures:

→ generic.debrick

root@OpenWrt:~# lspci -vv
00:11.0 Network controller: Atheros Communications Inc. AR922X Wireless Network Adapter (rev 01)
	Subsystem: Atheros Communications Inc. Device a097
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 168, Cache Line Size: 32 bytes
	Interrupt: pin A routed to IRQ 72
	Region 0: Memory at 10000000 (32-bit, non-prefetchable) [size=64K]
	Capabilities: [44] <chain broken>
	Kernel driver in use: ath9k

00:12.0 Network controller: Atheros Communications Inc. AR922X Wireless Network Adapter (rev 01)
	Subsystem: Atheros Communications Inc. Device a096
	Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
	Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
	Latency: 168, Cache Line Size: 32 bytes
	Interrupt: pin A routed to IRQ 73
	Region 0: Memory at 10010000 (32-bit, non-prefetchable) [size=64K]
	Capabilities: [44] Power Management version 2
		Flags: PMEClk- DSI- D1- D2- AuxCurrent=100mA PME(D0+,D1-,D2-,D3hot+,D3cold-)
		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
	Kernel driver in use: ath9k

Correct serial pinout:

A collection of photos on how to open the case, of the PCB and the serial port can be found on https://picasaweb.google.com/111743287730172647732/BuffaloWZRHPAG300HHardwarePhotos .

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

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

1. Open case
2. Locate serial port pads next to the Movie Engine switch
3. Pinouts beginning from the square pad: vcc, gnd, tx, rx
4. Sends at 115200 8N1 as shipped
5. Voltage is 3.3 V

→ hardware.button on how to use and configure the hardware buttons.

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