ASUS RT-N66U

Overview
Simultaneous Dual-Band, Gigabit Ethernet, 3x3:3 (450Mbps)
 * FCC ID: MSQ-RT0K00 - ASUS RT-N66U - PCB Rev.3.3

This router is sold in some locations as the RT-N66R.
 * It is also available in white as the RT-N66W.

The CPU is part BCM4706KPBG. The switch is part BCM53125SKMML.
 * Revision B2 is the same as B1, but have different CFE version.

Annihilator666's photos have a sticker on the device showing an:
 * Asus_RT-N66U (pictures)
 * OUI of 10:BF:48, LAN OUI of 20:CF:30, presumably, 50:46:5D OUI


 * ASUS RT-N66U C1 (MSQ-RTACHC00) • Product page • Support page


 * ASUS RT-N66U C1 on SmallNetBuilder forums
 * Model: RT-N66U C1, H/W ver B2, F/W ver 3.0.0.4.382_19333
 * CPU: Broadcom BCM4708 (ARM); 1x USB 3.0, 1x USB 2.0
 * (odmpid == "RT-N66U_C1" || odmpid =="RT-AC66U_B1" || odmpid == "RT-AC1750_B1")

Reviews

 * Reviewed on FoxNetwork
 * Reviewed on SmallNetBuilder

Forum threads

 * Asus RT-N66U on wl500g.info forums
 * Internals and boot log on VR-Zone forums
 * Info from BrainSlayer (DD-WRT forums),
 * now fully supported as of March 25

Other

 * How to flash RT-N66U with Shibby's TomatoUSB firmware
 * (SOLVED) Need help debricking my RT-N66U
 * Temperature.sh for Asus RT-N66U for Tomato
 * Stealth Mode (Timer function) RT-N66
 * RT-N66U cfe - Original
 * RT-N66 CFE Thread
 * Flashing DD-WRT onto Asus RT-N66U
 * Merlin mod of official firmware Asus
 * On the DD-WRT forum
 * On the TomatoUSB forum
 * On the TomatoUSB forum again
 * On the SNB forum
 * On the SNB forum
 * TomatoUSB VPN
 * TomatoUSB (Shibby) on the RT-N66U
 * Label shot and misc. pictures

Flashing dd-wrt
Asus RT-N66U on DD-WRT wiki

NVRAM issue
As of June 2012 there is an issue with NVRAM all but being filled by the default DD-WRT installation. Until this issue is resolved, please know about the pro and cons of this issue, before you install DD-WRT on this router.

There are however frequent general news about this issue. If not daily, then weekly news. And eventually a solution to (preferably a 60/64K solution) will also reach the DD-WRT community.

As of this writing (June 30, 2012) https://github.com/RMerl/asuswrt-merlin/downloads has implemented a solution, that lives with 32k NVRAM for CFE, but extends to ~60k in firmware.

As of July 16, 2012, TomatoUSB, Shibby has implemented a 64k NVRAM solution that lives with 32K NVRAM for CFE See Flashing TomatoUSB

Principle steps

 * Clear settings (Clear NVRAM) select Factory Default settings


 * Install the INITIAL ASUS RT-N66U version of DD-WRT (file name ends in .trx) using either the Web GUI method or the Recover Utility method. Both methods are described below


 * Clear settings (Clear NVRAM) select Factory Default settings


 * "Upgrade" to your final version of DD-WRT (filename ends in .bin) using Web GUI or Recovery Utility


 * Clear settings (Clear NVRAM) select Factory Default settings


 * Note: is IMPORTANT to Clear NVRAM (to select Factory Default settings) BEFORE and AFTER upload of any new firmware.

Upload Firmware via Web GUI

 * Clear settings (Clear NVRAM) select Factory Default settings.


 * Upload the .trx file using the stock web GUI.


 * Wait for the router to re-boot on its own. This may easily take 10–15 minutes to happen, so just be patient.


 * Clear settings (Clear NVRAM) select Factory Default settings. Wait for the router to re-boot on its own!!! May take 10 minutes or more

Upload Firmware via Recovery Utility

 * Set your NIC card to static IP 192.168.1.12, Subnet 255.255.255.0 , Default gateway 192.168.1.1 (Static IP guide)


 * Put router into recovery mode by holding down the reset button while powering up the router, wait until the power led is blinking slowly, then release the reset button.


 * In the Asus Recover utility Access the router’s built in recovery mode by issuing 192.168.1.1 in browser field.


 * Flash the initial DD-WRT build (e.g.) Asus-RT-N66U_18946_mini.trx build and upload.


 * When completed wait until the router re-boots on its own. This takes at least 10 minutes.


 * Put router into recovery mode by holding down the reset button while powering up the router, wait until the power led is blinking slowly, then release the reset button.


 * Flash the final DD-WRT build, could be any of:
 * 18946 Mega
 * 18946 Big
 * 19342 Mega
 * 19342 Big

Simple Instructions (Works for most)
1 Holding the reset botton with out energy cable, connect energy cable and switch
 * on the router with the reset botton pressed till the "on" led blinks slowly.

2 Try  and now you see the MiniWebserver.



3 Klick Durchsuchen und in the Fileserver search the Firmware.trx and click open.

(Click Browse and in the Fileserver search locate the Firmware.trx and click open.)

Now click Upload



4 When the firmware fully loaded click Continue.

You are back to the MiniWebServer, now click Restore default NVRAM values.



5 Now get  into the Browser and press Enter



6 Now click Continue and then click Reboot

7 Try  and set Username and Password



If you are not fast enough and the router reboots then you can do step
 * 1,Clear NVRAM and do step 5&6 without loading firmware again.


 * When completed wait until the router re-boots on its own. This takes at least 10 minutes.


 * Put router into recovery mode by holding down the reset button while powering up the router,
 * wait until the power led is blinking slowly, then release the reset button.


 * Select Reset NVRAM defaults when it completes (should be quick), in the browser field,
 * type in.


 * When done press enter. When complete select reboot and wait 5–10 minutes
 * for the router to reboot and start building its layers.


 * Now you should be able to access via web gui 192.168.1.1 and it should be DD-WRT.

Flashing Tomato

 * Shibby's Mod
 * Toastman's Mod


 * 1) Set static IP address on computer of 192.168.1.10
 * 2) Download the file 'tomato-K26USB-1.28.RT-N5x-MIPSR2-101-AIO-64K.trx'
 * 3) Put the router into recovery mode by holding down the reset button in the back of the router and plug the power in. Continue holding the reset button until the power lights blinks slow, then release the reset button.
 * 4) Use the Asus recovery disk and upload the tomato firmware.
 * 5) Wait until it finish, about 5min. If you do not wait you will brick it.
 * 6) Power down the router.
 * 7) Power up the router and you now have tomato on it.
 * 8) Reset nvram (Thorough).

JTAG
RT-N66U Jtag On DD-WRT forum

JTAG Pinouts
J2 sure looks like a JTAG header 1 © nTRST | 2 ® GND 3 © TDI  |  4 ® GND 5 © TDO  |  6 ® GND 7 © TMS  |  8 ® GND 9 © TCK  | 10 ® GND

Serial
Console connection on N66U and TUMPA board On DD-WRT forum

Serial Pinouts
Serial is J1 Serial is J1 R| VCC 1 © |F E| RX  2 © |R A| TX  3 © |O R| GND 4 © |N |T

DD-WRT VLAN Info
VLAN Support

Pictures
Asus' RT-N66U 

Hardware Modification

 * CFE bootloader update

MicroSD
After sticking in a 2GB MicroSD card and rebooting, the card is seen and mounted to /tmp/mnt/sda1 Contents can be shared via samba in OEM firmware, now to figure out how to run custom scripts from the oem firmware.

Mounted MicroSD Card in TomatoUSB
Card was partitioned and formated in Ubuntu with GParted



On InfoDepot Moved to TechInfoDepot Info from BrainSlayer (DD-WRT forums) Internals and boot log on vr-zone forums Reviewed on SmallNetBuilder
 * TomatoUSB (shibby) on the RT-N66U

LAN OUI of 20:CF:30, presumably. This is assumed to be a BCM4706 device.

Trouble with recovery mode
mhchm

I just want to give a tip for anybody who has trouble getting into recovery mode. I didn't find this simple information on the internet yet. First, some context:

I flashed a Brainslayer build from a Fractal build, and then my router stopped responding to ping. When booting normally, the power and ethernet LEDs would light up. The same thing happened when booting up with the reset button pressed, which should have put into recovery mode, but didn't. When booting up with the WPS button pressed, the power LED would flash and clear the NVRAM. The router then started up and enabled the two radios, broadcasting a "dd-wrt" SSID, but still no ping.

To force it into recovery mode:


 * 1) Set a static IP of 192.168.1.2
 * 2) Press the WPS button and start up
 * 3) Let the power LED flash rapidly for 5 seconds, then release WPS
 * 4) Immediately press the reset button, keeping it pressed until the power LED flashes slowly
 * 5) Release the reset button
 * 6) Point your browser to 192.168.1.1

Voilà.