Serial pinout and OpenWrt on Netgear board WNDR4000 rev.0

At last week I installed OpenWrt on my Nergear WNDR4000.
The chip on the board is marked as U12H194T99 instead of *T00, which sets on board rev.1.
The most of staff in the web is about T00, so, it wasn’t so easily find something about T99.
I did a mistakes and got experience. So, I collected a couple of advices for you, %username%.

I prefer to look for boot log and other things during device boot, so, for the beginning, I soldered uart’s pins on board to using serial port.
pinout serial image3
I used arduino uno with unmounted atmega chip as provider uart’s rx/tx to usb.

Empirical I’ve found board’s pinout, they’re the following:

* note: pin number starts from blunt corner.
Connecting arduino’s Tx to board’s Rx, Rx to Tx and grounds will be enough.

Next you need to download build of openwrt version 15.05, because 14.07 isn’t working well with bridges on wndr4000, it’s really important if you change your “looking-to-the-world” mac address. Also in

Links: openwrt-15.05-brcm47xx-mips74k-netgear-wndr4000-squashfs.chk from

Can’t say exactly, could you install openwrt from original firmware with dot-chk file or not, because I’d already installed openwrt 14.07, so, I update it over serial console using: $ sysupdate -i /tmp/openwrt-15.05-brcm47xx-mips74k-netgear-wndr4000-squashfs.chk Comfortably, the board have the usb port: you don’t care about doing something wrong with network – you can upload another openwrt version through usb.

Dunno why openwrt detect 5 devices on my board, but there is only 2 physical devices:

Generic 802.11 Wireless Controller (radio0)Spirit
Generic 802.11 Wireless Controller (radio1)Spirit
Generic MAC80211 802.11bg (radio2)Real
Generic MAC80211 802.11bg (radio3)Real
Broadcom 802.11 Wireless Controller (wl0)Spirit
“Spirits” were not associated with a real devices and turning them on didn’t gives any result.

All other staff to configure router is available in the net, so, have fun!

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