Some more notes on ASUS RT-N66U, firmwares, temperatures and versions
Posted by jpluimers on 2014/08/20
In the the irregular series of ASUS RT-N66U and TomatoUSB posts:
Execute this script from the Tomato USB interface, or a ssh/telnet shell:
cat /dev/mtd0ro | grep bl_version
nvram get os_version
nvram get clkfreq
wl -i eth1 phy_tempsense | awk '{print $1/2+20;}'
wl -i eth2 phy_tempsense | awk '{print $1/2+20;}'
- Line 1 gets the CFE bootloader version
(1.0.2 and lower boot with 32K of NVRAM, 1.0.3 and up with 64K of RAM; some Firmwares work around the 32k limitation) - Line 2 gets the Firmware model and version
- Line 3 gets the CPU speed
- Line 4 and 5 get the temperature for eth1 (2.4 Ghz) and eth2 (5 Ghz) in Celsius
It is based on the RMerlinDev (firmware developer) information on temperatures: These are for each radio. Take the returned value, divide by 2, then add 20. Results are in Celcius.
Next to that knowledge, it uses a few tricks on awk calculation, and first parameter in awk (the second parameter would be the hex value of the temperature code in parenthesis) which is easier than shell calculations.
Based on those, I found a few very useful scripts:
- Backup Settings, Logs, & More to USB Drive Script – TomatoUSB.
- Temperature.sh for Asus RT-N66U | LinksysInfo.org.
- RRDStorm – A RRDTool graph tool for routers.
- The gadget blog: Asus RT-N66U with openVPN server.
- Running Asus RT-N66U stock firmware as Time Capsule (Time Machine).
- Asus RT-N66U.
–jeroen
The Wiert Corner - irregular stream of stuff 
Leave a comment